---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Tue 03/11/08: 70 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:21 AM - Re: Re: Accident (William Dominguez) 2. 05:33 AM - Re: XL - success stories (PatrickW) 3. 06:08 AM - Re: CH640 Performance Numbers (steveadams) 4. 06:16 AM - Re: Re: Overtrimmed airleron (japhillipsga@aol.com) 5. 06:23 AM - Re: Re: Overtrimmed airleron (japhillipsga@aol.com) 6. 06:35 AM - Re: Re: XL - success stories (Trainnut01@aol.com) 7. 06:42 AM - Re: XL - success stories (Gig Giacona) 8. 06:50 AM - Re: Fuel Pump & Gascolator For Sale (Gig Giacona) 9. 07:21 AM - Re: Accident (MHerder) 10. 07:22 AM - Re: Re: XL - success stories (Darrell Haas) 11. 07:33 AM - Re: XL - success stories (Gig Giacona) 12. 07:43 AM - Re: Re: Accident (John Davis) 13. 08:03 AM - Re: Accident (ashontz) 14. 08:05 AM - Re: Accident (Tim Juhl) 15. 08:14 AM - Re: Re: XL - success stories (John Bolding) 16. 08:18 AM - Re: Accident in Spain was a Zodiac 601XL and there is a picture. (ashontz) 17. 08:43 AM - Re: Accident (MHerder) 18. 08:52 AM - Re: Accident (ashontz) 19. 09:01 AM - Re: Accident in Spain was a Zodiac 601XL and there is a picture. (Gig Giacona) 20. 09:15 AM - Re: Re: Accident in Spain was a Zodiac 601XL and there is a picture. (Paul Mulwitz) 21. 09:27 AM - accident (alex trent) 22. 09:32 AM - Re: Re: XL - success stories (Debo Cox) 23. 09:32 AM - Re: Fuel Pump & Gascolator For Sale (ricklach) 24. 09:53 AM - Re: Re: Accident in Spain was a Zodiac 601XL and there is a picture. () 25. 10:17 AM - Re: accident (Darrell Haas) 26. 10:18 AM - Re: Re: Accident (ella) 27. 10:20 AM - Re: Accident (ashontz) 28. 10:21 AM - Re: Re: XL - success stories (Juan Vega) 29. 10:46 AM - Re: Re: Accident in Spain was a Zodiac 601XL and there is a picture. (Kevin Bonds) 30. 10:50 AM - Re: accident (Iberplanes IGL) 31. 10:55 AM - Re: Re: Accident in Spain (Iberplanes IGL) 32. 11:02 AM - Re: Re: Accident (John Davis) 33. 11:05 AM - Re: accident (Randy) 34. 11:08 AM - Re: XL - success stories (swater6) 35. 11:25 AM - Re: accident (William Dominguez) 36. 11:46 AM - 601 XL Down in Barcelona (Iberplanes IGL) 37. 11:52 AM - Re: Accident (swater6) 38. 11:57 AM - Skins (Bob McArdle) 39. 12:04 PM - Re: Re: XL - success stories (tlski) 40. 12:11 PM - Re: Re: XL - success stories (Craig Payne) 41. 12:32 PM - Re: Skins (eddies) 42. 12:58 PM - Re: 601 XL Down in Barcelona (Kevin Bonds) 43. 01:01 PM - Re: Skins (frank forgues) 44. 01:11 PM - Re: Accident (n85ae) 45. 01:12 PM - Re: Re: Accident (Larry H) 46. 01:18 PM - Re: accident (Larry H) 47. 01:49 PM - Re: Re: Accident (Kevin Bonds) 48. 01:49 PM - Re: accident (Iberplanes IGL) 49. 01:57 PM - Re: Accident (Iberplanes IGL) 50. 02:35 PM - Re: accident (Kevin Bonds) 51. 02:43 PM - Re: accident (Steve Shuck) 52. 03:35 PM - Re: Accident (swater6) 53. 05:02 PM - Re: Accident (ashontz) 54. 05:03 PM - Re: Skins (leinad) 55. 05:05 PM - Re: Skins (leinad) 56. 05:13 PM - Re: Re: XL - success stories (Gary Gower) 57. 05:18 PM - Re: Re: Accident (Gary Gower) 58. 05:48 PM - Re: Re: Accident (Jaybannist@cs.com) 59. 05:56 PM - brs chute ? (Tracy) 60. 06:06 PM - Re: Accident (ashontz) 61. 06:15 PM - Re: Re: Accident (Kevin Bonds) 62. 06:27 PM - Accident (Jaybannist@cs.com) 63. 06:49 PM - Re: Accident (Paul Riedlinger) 64. 07:06 PM - Re: Accident (Craig Payne) 65. 07:31 PM - Re: Accident () 66. 07:31 PM - Re: brs chute ? (cookwithgas) 67. 07:42 PM - Re: XL - success stories (cookwithgas) 68. 08:40 PM - Fish Eye Update (steve) 69. 09:24 PM - Re: Accident (Jay Maynard) 70. 11:00 PM - Re: Accident (mwtucker) ________________________________ Message 1 _____________________________________ Time: 05:21:49 AM PST US From: William Dominguez Subject: Re: Zenith-List: Re: Accident All confirmed and unconfirmed wing failures have happened with the 601 XL and one 601 UL in the UK. The 601UL wing failure in the UK was determined to be due to over stressing the airframe during a hard pull but all of 601 XL cases are still inconclusive. William Dominguez Zodiac 601XL Plans Miami Florida http://www.geocities.com/bill_dom Jeyoung65@aol.com wrote: Just my $0.02. In so far as there is a big difference between the 601HD(S) and the 601XL wing has anyone looked as which type is being reported(?) as having wing failure? Is there any report that has confirmed a wing failure on any 601? Jerry of Ga. DO NOT ARCHIVE In a message dated 3/10/2008 12:14:18 P.M. Eastern Daylight Time, nyterminat@aol.com writes: Andy, What no BRS chute???????????????? Regardless, I'm adding extra ribs, going with the 12 gallon tanks instead of the 15, no wing-locker, and some sort of overridable system that limits control surface/stick travel at and above manuevering speed. .. --------------------------------- It's Tax Time! Get tips, forms and advice on AOL Money & Finance. ________________________________ Message 2 _____________________________________ Time: 05:33:00 AM PST US Subject: Zenith-List: Re: XL - success stories From: "PatrickW" Do you guys ever feel like you have to defend the Zodiac when talking to builders of other airplanes? Patrick XL/Corvair Read this topic online here: http://forums.matronics.com/viewtopic.php?p=168971#168971 ________________________________ Message 3 _____________________________________ Time: 06:08:59 AM PST US Subject: Zenith-List: Re: CH640 Performance Numbers From: "steveadams" I finished my 640 about 2 1/2 years ago. It'll do 130 kts TAS at gross, but I generally cruise at 125 kts. Other performance numbers are pretty much in line with those on the CH640 website. With 600 hours on it so far, I am happy with my choice and would build the same plane again. It took me about 750 hours over the course of 14 months to complete the QB kit and have it in the air, including paint. It's a relatively easy, straight forward build and the QB kit is well made and what has been done at the factory is well documented. I have plans to modify the cowl to close off some of that huge inlet and decrease cooling drag, but that will probably not happen until I have to have the plane grounded for engine overhaul someday. It's really in it's own class as far as experimentals go, intermediate between the common 2 seat designs and the heavier 540 powered 4 seat designs, with the sportsman 2+2 about the only comparable kit that I know of. So if your looking for a 4 seater that is economical and fairly simple to build and maintain I don't think you can go wrong. Steve Adams N621J Read this topic online here: http://forums.matronics.com/viewtopic.php?p=168975#168975 ________________________________ Message 4 _____________________________________ Time: 06:16:08 AM PST US Subject: Re: Zenith-List: Re: Overtrimmed airleron From: japhillipsga@aol.com Paul, it was one of those "you had to be there" moments. Bill do not archive -----Original Message----- From: paulrod36@msn.com Sent: Fri, 7 Mar 2008 1:01 pm Subject: Re: Zenith-List: Re: Overtrimmed airleron Bill, are you sure you stretched your cables?? As I recall, they have about a 900 pounds-plus capability, which ought to bend structure before breaking.? Doesn't seem like a nasty landing ought to do that. ? Paul Rodriguez ----- Original Message ----- From: japhillipsga@aol.com Sent: Friday, March 07, 2008 10:29 AM Subject: Re: Zenith-List: Re: Overtrimmed airleron Dear fellow 601 Builders/Flyers, I may be hijacking this, but is anyone familiar with some posts a couple years ago involving adjusting ailerons down a bit?? I seem to remember several flyers were experimenting with drooping them a tad for better control or performance or some reason. Who out there did this and what was the results? For the last year since I stretched my cables in a crosswind balloon landing my XL seems more "twitchy" in climb to TOC. Maybe the ailerons are too high or too tightly adjusted? Hope to hear from some builder/flyers. Thanks, Bill of Georgia? -----Original Message----- From: xl Sent: Fri, 7 Mar 2008 1:56 am Subject: Re: Zenith-List: Re: Overtrimmed airleron ? I've posted a glimpse at http://www.cleanh2o.com/633z/aileron_hinge_patch.jpg? A repolish is in the queue for the Arlington, WA flyin.? ? Joe E @ BFI? CH601XL, 505 hours? http://www.cleanh2o.com/633z/? ? On Thu, 7 Feb 2008, ashontz wrote:? > Thanks, I appreciate it. I'd like to see you're handywork up close.? >? > xl(at)prosody.org wrote:? >> I made the same mistake on both ailerons.? >> I didn't see the mistake until I fit ailerons to the wings.? >> I took a piece of scrap wide enough to get a rivet in on? >> each side. No one has noticed the patch until I point it out.? >> (or they've been polite)? >> .......snip? >> It's the only picture that I can find that shows the patch.? >> I see if my camera still works, if it does I'll get a closeup.? >>>>> do not archive? ? ? ? Supercharge your AIM. Get the AIM toolbar for your browser. href="http://www.matronics.com/Navigator?Zenith-List">http://www.matronhref="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c ________________________________ Message 5 _____________________________________ Time: 06:23:19 AM PST US Subject: Re: Zenith-List: Re: Overtrimmed airleron From: japhillipsga@aol.com Leo, thanks for the info. I don't notice the "twitchy" effect in moderate climb (say 500 fpm or less), level flight or decent. Only on initial climb out, max power, nose?up scratching for altitude accent. Usually, 1K fpm + @ 100 mph or better. I know the nose up configuration is decreasing stability, but my AOA LRI is buried in the green so I'm nowhere near a stall. Bill -----Original Message----- From: Leo Gates Sent: Fri, 7 Mar 2008 3:20 pm Subject: Re: Zenith-List: Re: Overtrimmed airleron ? Bill, On my 601HDS, I placed a dial type level on top of the top longeron on the side of the cockpit. I originally found I was flying 2 degrees nose high at level normal cruise. I started drooping both ailerons a 1/2 turn at a time. ( I thought I had them neutral, eyeball of course) At zero on the level, I picked up _4 MPH_ at cruise. At negative angles, I again lost speed. I did not detect any change on control sensitivity at any setting.? ? Leo Gates? N601Z - CH601hds TDO? Rotax 912UL? ? ? japhillipsga@aol.com wrote:? > Dear fellow 601 Builders/Flyers, I may be hijacking this, but is > anyone familiar with some posts a couple years ago involving adjusting > ailerons down a bit? I seem to remember several flyers were > experimenting with drooping them a tad for better control or > performance or some reason. Who out there did this and what was the > results? For the last year since I stretched my cables in a crosswind > balloon landing my XL seems more "twitchy" in climb to TOC. Maybe the > ailerons are too high or too tightly adjusted? Hope to hear from some > builder/flyers. Thanks, Bill of Georgia ? ? ? ________________________________ Message 6 _____________________________________ Time: 06:35:53 AM PST US From: Trainnut01@aol.com Subject: Re: Zenith-List: Re: XL - success stories Patrick The short answer is yes. I do have to defend my choice if not the airplane itself. However I have found that other flyers reactions are kind of relative. My first home built was a RV7. After my doctor suggested that I might want to start thinking LSA I sold the RV and started building my XL. Initially most of my flying friends were from the RV community and these guys really don't have much regard for anything from Zenith. Then my son bought an ultra light and soon had me involved with a whole different crowd. That's when I discovered that while RV guys think the XL is junk the ultra light guys think the XL is "cool". I'm not suggesting that we all need new friends but it worked for me. Carroll XL/Corvair do not archive. **************It's Tax Time! Get tips, forms, and advice on AOL Money & Finance. (http://money.aol.com/tax?NCID=aolprf00030000000001) ________________________________ Message 7 _____________________________________ Time: 06:42:30 AM PST US Subject: Zenith-List: Re: XL - success stories From: "Gig Giacona" Only the hinge-less ailerons. Though most of the "old guys" at my airport have come around to the design simplicity and and self tested ruggedness. After he looked at my wings the first time a few years back he asked if I had a scrape peice of the same aluminum. I handed him a peice. I stopped by his hanger a few weeks later and he had the piece in the vice and was sitting talking with the other "old guys" and flexig it pretty close to the amount it would flex in the plane. (He had looked at my plans.) One of the other "old guys" told me he had been doing that at least one hour a day since he got the metal from me. He stopped by my hanger about two weeks later and handed me the metal and said, "Yea that ought to work." PatrickW wrote: > Do you guys ever feel like you have to defend the Zodiac when talking to builders of other airplanes? > > Patrick > XL/Corvair -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=168984#168984 ________________________________ Message 8 _____________________________________ Time: 06:50:21 AM PST US Subject: Zenith-List: Re: Fuel Pump & Gascolator For Sale From: "Gig Giacona" If you are doing the WW fuel system and haven't bought the replacement gasolator yet Zenith will trade you that one for one without the welded tabs. [quote="a.s.elliott(at)cox.net"]Gang: I have the following unused (new) fuel system parts for sale: Facet 40105 Fuel Pump - $20 + shipping ($29.75 from AS&S, $42 from Zenith) Zenith-mod (with tabs) Gascolator - $45 + shipping ($62.75 from AS&S, $81.40 from Zenith) I modified my fuel system and these are now surplus to my needs. Save me some time and get both for $60 + shipping! Please contact me off-list. Andy Elliott, Mesa, AZ N601GE (reserved) 601XL/TD, Corvair, building... > [b] -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=168988#168988 Attachments: http://forums.matronics.com//files/fuel1_363.jpg ________________________________ Message 9 _____________________________________ Time: 07:21:01 AM PST US Subject: Zenith-List: Re: Accident From: "MHerder" Disclaimer: The information contained below is filled with my own personal assumptions, many of which may not be correct (I am only trying to use my best logic) I do not wish to be involved in a flaming session since this is a very touchy subject for those of us (myself included) who truly take pride in their project and enjoy every second of working on their project and have invested a large amount of time and money. I am only trying to ask some questions and get others opinions as to whether or not my assumptions are logical or reasonable. Does anyone know if the incident in Spain and Australia involved the UL version of the XL, or the UL version of the HD. Zenair apparently manufactures the "ultralight" version for the euro market ( I don't know what is required in Australia). As a builder I am deeply concerned, my condolences go out to the families effected. The reason I ask is that the UL version is about 200 or so pounds less (gross weight). I look at the structure of my aircraft under construction and wonder where the hell I could take out such a significant amount of weight without making sacrifices somewhere. (Lighter landing gear seems to be the largest component) I DO NOT believe that Zenith is marketing and selling a dangerous design. Someone once pointed out that all of the significant fly in the XL frequently, which I think is a very valid point. However, I was more easily able to dismiss the first two or so incidents. This latest series is especially bothersome. My searches find 2 down in Cali with apparent wing failures, 1 down in Canadian TX. All of the three point to wing failures, add 2 to it and it brings us up to 5 Zodiac XL's with apparent wing failures. In an approximately 2 or so year span. How many Zodiac XL's are flying? FAA (which only shows registrations for US owned) shows about 225 or so. If we assume ( and this is a giant assumption) that the US market represents 60-70% of all Zodiac flying Zodiac XL's to about 3-400 FLYING Zodiac XL's. Can someone please substantiate or reject these approximations? I don't even consider the HD in these numbers because the wing is an entirely different spar design (we are talking about wing failures not rudder failures) If it were rudder failures I would consider their flying numbers in my figures since they both use the same rudder. What is the average number of hours on each Zodiac XL at this point in time? My guess would be about 150-200. (This is only my wild guess). So is it safe to say that there is 1 wing failure per 15000 hrs flown in a Zodiac XL? If you fly in a Zodiac for 500 hrs do you have an 3.3% chance of experiencing a wing failure? Guys I'm just trying to rattle around some numbers, I think my numbers are conservative. (More zodiacs than there actually are flying, more hours on each than there actually are etc.) I feel confident that if there is a design flaw Zenith will address the issue appropriately, hopefully the wreckage is in such condition that it can yield better information than the other wrecks that were inconclusive due to post crash fire. Hopefully the landing in the ocean in relatively shallow waters will allow for a more conclusive investigation. My thoughts and prayers go out to the families. If only one good thing comes of this accident, please let it be that IF there is a design issue, that it can be addressed. -------- One Rivet at a Time! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=168995#168995 ________________________________ Message 10 ____________________________________ Time: 07:22:21 AM PST US From: "Darrell Haas" Subject: Re: Zenith-List: Re: XL - success stories YES! All of my EAA group are Van's builders and they really let you know it. Darrell 601XL do not archive On 3/11/08, PatrickW wrote: > > Do you guys ever feel like you have to defend the Zodiac when talking to builders of other airplanes? > > Patrick > XL/Corvair > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=168971#168971 > > ________________________________ Message 11 ____________________________________ Time: 07:33:17 AM PST US Subject: Zenith-List: Re: XL - success stories From: "Gig Giacona" That's where I'm better off. My fellow EAA members here that do build seem to all have Kitfoxes. I'll be the speed demon of the bunch. darrellhaas(at)gmail.com wrote: > YES! All of my EAA group are Van's builders and they really let you know it. > Darrell > 601XL > do not archive > > On 3/11/08, PatrickW wrote: > > > > > > > Do you guys ever feel like you have to defend the Zodiac when talking to builders of other airplanes? > > > > Patrick > > XL/Corvair > > > > > > > > > > Read this topic online here: > > > > http://forums.matronics.com/viewtopic.php?p=168971#168971 > > > > > > > > > > > > > > > > > > > > > > > > > > > -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169000#169000 ________________________________ Message 12 ____________________________________ Time: 07:43:58 AM PST US From: John Davis Subject: Re: Zenith-List: Re: Accident Hi Michael, As a 601XL builder I too am concerned but would like to add a couple of data points to this discussion: 1. The accident in Canadian, TX looks like it involved thunderstorms and I've read lots of cases of certified aircraft with wings coming off in such cases. So I'm not sure we can really point to an unexpected wing failure in this case. 2. The recent Australian case hasn't been show to have been caused by a wing failure. I think folks are jumping the gun on this one. What strikes me as odd is that they have found pieces of the canopy over land which would seem indicate that the canopy was damaged early in the accident. The wing apparently wasn't found with this debris. I wonder about a bird strike in this one...It will be interesting to see what they find when they locate the plane. Apparently thats supposed to happen later this week when the bad weather they are having subsides... John Davis Burnsville, NC 28714 601XL - Jab 3300 MHerder wrote: > > Disclaimer: The information contained below is filled with my own personal assumptions, many of which may not be correct (I am only trying to use my best logic) I do not wish to be involved in a flaming session since this is a very touchy subject for those of us (myself included) who truly take pride in their project and enjoy every second of working on their project and have invested a large amount of time and money. I am only trying to ask some questions and get others opinions as to whether or not my assumptions are logical or reasonable. > > Does anyone know if the incident in Spain and Australia involved the UL version of the XL, or the UL version of the HD. Zenair apparently manufactures the "ultralight" version for the euro market ( I don't know what is required in Australia). As a builder I am deeply concerned, my condolences go out to the families effected. > > The reason I ask is that the UL version is about 200 or so pounds less (gross weight). I look at the structure of my aircraft under construction and wonder where the hell I could take out such a significant amount of weight without making sacrifices somewhere. (Lighter landing gear seems to be the largest component) > > I DO NOT believe that Zenith is marketing and selling a dangerous design. Someone once pointed out that all of the significant fly in the XL frequently, which I think is a very valid point. > > However, I was more easily able to dismiss the first two or so incidents. This latest series is especially bothersome. > > My searches find 2 down in Cali with apparent wing failures, 1 down in Canadian TX. All of the three point to wing failures, add 2 to it and it brings us up to 5 Zodiac XL's with apparent wing failures. In an approximately 2 or so year span. How many Zodiac XL's are flying? FAA (which only shows registrations for US owned) shows about 225 or so. If we assume ( and this is a giant assumption) that the US market represents 60-70% of all Zodiac flying Zodiac XL's to about 3-400 FLYING Zodiac XL's. Can someone please substantiate or reject these approximations? I don't even consider the HD in these numbers because the wing is an entirely different spar design (we are talking about wing failures not rudder failures) If it were rudder failures I would consider their flying numbers in my figures since they both use the same rudder. > > What is the average number of hours on each Zodiac XL at this point in time? My guess would be about 150-200. (This is only my wild guess). > > So is it safe to say that there is 1 wing failure per 15000 hrs flown in a Zodiac XL? If you fly in a Zodiac for 500 hrs do you have an 3.3% chance of experiencing a wing failure? > > Guys I'm just trying to rattle around some numbers, I think my numbers are conservative. (More zodiacs than there actually are flying, more hours on each than there actually are etc.) > > I feel confident that if there is a design flaw Zenith will address the issue appropriately, hopefully the wreckage is in such condition that it can yield better information than the other wrecks that were inconclusive due to post crash fire. Hopefully the landing in the ocean in relatively shallow waters will allow for a more conclusive investigation. My thoughts and prayers go out to the families. > > If only one good thing comes of this accident, please let it be that IF there is a design issue, that it can be addressed. > > -------- > One Rivet at a Time! > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=168995#168995 > > > ________________________________ Message 13 ____________________________________ Time: 08:03:17 AM PST US Subject: Zenith-List: Re: Accident From: "ashontz" I'm going to install a BRS chute for sure. nyterminat(at)aol.com wrote: > Andy, What no BRS chute???????????????? > > > > > > > > > Regardless, I'm adding extra ribs, going with the 12 gallon tanks instead of the > > > 15, no wing-locker, and some sort of overridable system that limits control > > > surface/stick travel at and above manuevering speed. > > > > > > > > > Kevin Bonds wrote: > > > > > > > > > -- -------- Andy Shontz CH601XL - Corvair www.mykitlog.com/ashontz Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169006#169006 ________________________________ Message 14 ____________________________________ Time: 08:05:15 AM PST US Subject: Zenith-List: Re: Accident From: "Tim Juhl" Regarding the article that Joe shared with us about the Australian crash, a bird strike was the first thought that came to my mind when I heard of pieces of the canopy ending up on shore, far from where the plane went in. At the altitude the plane was at if the pilot took a bird in the face he might not have had much time to react and could easily have lost control. We had an incident at our local airport where a Beech Sundowner being flown by a student with his instructor hit a bird (maybe Canada Goose) on final approach at night. He was going about 80 mph when he experienced an impact that slewed the plane around. He later said he thought he'd hit a skydiver. Upon landing a hole was found in wing skin just outboard of the fuel tank from the leading edge to the spar and beyond. It was big enough to stuff a frozen turkey into. The way the skin was peeled you would have thought he'd taken an artillery round. The insurance company decided to replace rather than repair the wing. A bird strike may not be responsible for the tragedy in Australia but it points out that we all need to be especially vigilant when flying in areas frequented by large fowl. I don't have a picture of the damaged wing but here is a shot of what a bird did to a Cherokee windshield. Tim (who lives near a major migratory bird route) -------- ______________ CFII Champ L16A flying Zodiac XL - Jabiru 3300A Working on fuselage Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169007#169007 Attachments: http://forums.matronics.com//files/birdstrike_117.jpg ________________________________ Message 15 ____________________________________ Time: 08:14:14 AM PST US From: "John Bolding" Subject: Re: Zenith-List: Re: XL - success stories Isn't it strange! When I built my RV3 about a hundred yrs ago it was like the Zenith group is now, bunch of guys building airplanes and having a good time, nobody had their nose in the air. Was at a fly-in (Texas) a month ago and a fellow with a fresh RV6 had his chest stuck way out and asked smugly if I ever thought about building an RV, answer was "Yep, built the second RV to fly in Texas before you were born". I'm a little abrasive sometimes. Hopefully the Zenith crowd doesn't get that way. Not all the RV guys are like that but there ARE a bunch of them. LO&SLO John ----- Original Message ----- From: "Darrell Haas" Sent: Tuesday, March 11, 2008 9:18 AM Subject: Re: Zenith-List: Re: XL - success stories > > YES! All of my EAA group are Van's builders and they really let you know > it. > Darrell > 601XL > do not archive > > On 3/11/08, PatrickW wrote: >> >> Do you guys ever feel like you have to defend the Zodiac when talking to >> builders of other airplanes? >> >> Patrick >> XL/Corvair >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=168971#168971 >> >> >> >> >> >> >> >> >> >> >> > > > ________________________________ Message 16 ____________________________________ Time: 08:18:51 AM PST US Subject: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is a picture. From: "ashontz" Didn't one of the others have it's wings break off AFTER an explosion? Not defending it one way or another, just trying to get the facts. Could be something wrong with the wing, could be the wings are just fine. I don't know. I wish I did. Either way I'd like to know for sure and either fix it or forget about it. What would cause an explosion, leaking fuel tank into the wing structure? Empty tank that for some reason exploded? Be nice to know if the explosion occured in the wing at all. I'm guessing it did. Also, the other one that had an explosion proceeding the accident was also in the landing pattern. Is there some clue here? Maybe switching tanks, flaps related, turning related? In these two cases I'm guessing they weren't going very fast in both cases. [quote="bill_dom(at)yahoo.com"]I found this from from the accident page of ultraligero.net, the entry is at the bottom: http://www.ultraligero.net/Accidentes/08.htm Here is a picture if you can make sense of it: http://www.ultraligero.net/Accidentes/sant_pau.jpg I've made a translation, keep in mind that I'm not a professional translator, just someone fluent in Spanish: 02/05/2008 Subirats (Barcelona) Zenair 601 XL Jordi Conesa 37, and Santiago F. A. 41 members of the Penedes club have died. The ultralight they where piloting crashed in an agricultural zone. The 2 victims where experimented pilots and all indications point to a mechanical failure. The aircraft crashed at 40 meters from the football camp at Sant Pau d' Ordal, the principal urban nucleus of the municipality. At that moment, the benjamines of the local team where training in the field. The accident was witnessed by numerous neighbors. The testimony of some of the witnesses indicate that the breakage of one of the wings, preceded by an explosion, was the cause of the accident. The pilots where returning the the airfield when they realized that it was getting dark. I will keep looking for more info and will post if something new show up. William Dominguez Zodiac 601XL Plans Miami Florida http://www.geocities.com/bill_dom Gary Gower [quote] Hello William, A least in a yahoo group from Spain, where they were members, in message 22607 from Feb 08/2008 they post that it was a 601 XL, Is in the only post (in lots of condolences and questions) that they mention about the possible airplane, but nothing else. Hope our friend "Iberplanes" can do a more certain follow up. I found the post doing a google search of "Jordi Conesa" the owner?s name (God Bless Him and his family). Saludos Gary Gower. Flying from Chapala, Mexico. William Dominguez wrote: > > Are you refering to this accident?: > > http://www.elpais.com/articulo/cataluna/muertos/estrellarse/avioneta/vinedo/Subirats/elpepiespcat/20080206elpcat_28/Tes > > The news doesn't mention make and model but it is about an 2 place aircraft that apparently lost a wing in flight. > > William Dominguez > Zodiac 601XL Plans > Miami, Florida > http://www.geocities.com/bill_dom > > > Iberplanes IGL wrote: > > We had an 601 XL down in Barcelona 2 month ago. Aparently, wing fold. > > > > > > > > 2008/3/10, Iberplanes IGL : > > > Si es por un ala, me comienza a preocupar. Voy a investigar y te cuento. > > > > > > saludos > > > > > > > > > ---------- Forwarded message ---------- > > > From: ashontz > > > Date: 10-mar-2008 12:55 > > > Subject: Re: Accident > > > To: zenith-list@matronics.com (zenith-list@matronics.com) > > > > > > > > > Regardless, I'm adding extra ribs, going with the 12 gallon tanks instead of the 15, no wing-locker, and some sort of overridable system that limits control surface/stick travel at and above manuevering speed. > > > > > > > > > Kevin Bonds wrote: > > > > > > > Andy, > > > > > > > > Let's not jump to any conclusions here. Sounds more like there may have > > > > been a problem with the canopy, if I had to guess--which we shouldn't. I > > > > know an eyewitness stated that a wing /may/ have come off, but I doubt > > > > many eyewitnesses would know a wing from a rudder or any other part in > > > > that instance. Hopefully they will recover the plane. The wings could, > > > > very well, still be intact. Sounds like the canopy will not be size="2"> > > > > [/b] > > > > > > > > > > > > > [b] -------- Andy Shontz CH601XL - Corvair www.mykitlog.com/ashontz Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169017#169017 ________________________________ Message 17 ____________________________________ Time: 08:43:49 AM PST US Subject: Zenith-List: Re: Accident From: "MHerder" John, Regarding Note 1. I concur, (this incident seems to have the most plausible explanation, simply flying in adverse conditions). However, you mention that "a lot of cases" of wing failures can be found in certified aircraft. I was quite surprised to find how few there really were. Perhaps my search parameters could be tight but when searching key words like wing failure, in flight break up etc not too many come up. Note 2 Yes a bird strike is certainly a possibility, Mythbusters has some dramatic showing videos that show the potential damage from a bird strike. A million things COULD have happened, but there appears to be a common thread in witness descriptions. Yes, I agree I wouldn't bet two cents on a witnesses ability to truly give the type of information necessary to actually find cause. However, all of the accounts seem to be consistent. Loud bang, wing fold, spiral to ground. johnd(at)data-tech.com wrote: > Hi Michael, > > As a 601XL builder I too am concerned but would like to add a couple of > data points to this discussion: > > 1. The accident in Canadian, TX looks like it involved thunderstorms and > I've read lots of cases of certified aircraft with wings coming off in > such cases. So I'm not sure we can really point to an unexpected wing > failure in this case. > > 2. The recent Australian case hasn't been show to have been caused by a > wing failure. I think folks are jumping the gun on this one. What > strikes me as odd is that they have found pieces of the canopy over land > which would seem indicate that the canopy was damaged early in the > accident. The wing apparently wasn't found with this debris. I wonder > about a bird strike in this one...It will be interesting to see what > they find when they locate the plane. Apparently thats supposed to > happen later this week when the bad weather they are having subsides... > > > John Davis > Burnsville, NC 28714 > 601XL - Jab 3300 > > MHerder wrote: > > > > > > > Disclaimer: The information contained below is filled with my own personal assumptions, many of which may not be correct (I am only trying to use my best logic) I do not wish to be involved in a flaming session since this is a very touchy subject for those of us (myself included) who truly take pride in their project and enjoy every second of working on their project and have invested a large amount of time and money. I am only trying to ask some questions and get others opinions as to whether or not my assumptions are logical or reasonable. > > > > Does anyone know if the incident in Spain and Australia involved the UL version of the XL, or the UL version of the HD. Zenair apparently manufactures the "ultralight" version for the euro market ( I don't know what is required in Australia). As a builder I am deeply concerned, my condolences go out to the families effected. > > > > The reason I ask is that the UL version is about 200 or so pounds less (gross weight). I look at the structure of my aircraft under construction and wonder where the hell I could take out such a significant amount of weight without making sacrifices somewhere. (Lighter landing gear seems to be the largest component) > > > > I DO NOT believe that Zenith is marketing and selling a dangerous design. Someone once pointed out that all of the significant fly in the XL frequently, which I think is a very valid point. > > > > However, I was more easily able to dismiss the first two or so incidents. This latest series is especially bothersome. > > > > My searches find 2 down in Cali with apparent wing failures, 1 down in Canadian TX. All of the three point to wing failures, add 2 to it and it brings us up to 5 Zodiac XL's with apparent wing failures. In an approximately 2 or so year span. How many Zodiac XL's are flying? FAA (which only shows registrations for US owned) shows about 225 or so. If we assume ( and this is a giant assumption) that the US market represents 60-70% of all Zodiac flying Zodiac XL's to about 3-400 FLYING Zodiac XL's. Can someone please substantiate or reject these approximations? I don't even consider the HD in these numbers because the wing is an entirely different spar design (we are talking about wing failures not rudder failures) If it were rudder failures I would consider their flying numbers in my figures since they both use the same rudder. > > > > What is the average number of hours on each Zodiac XL at this point in time? My guess would be about 150-200. (This is only my wild guess). > > > > So is it safe to say that there is 1 wing failure per 15000 hrs flown in a Zodiac XL? If you fly in a Zodiac for 500 hrs do you have an 3.3% chance of experiencing a wing failure? > > > > Guys I'm just trying to rattle around some numbers, I think my numbers are conservative. (More zodiacs than there actually are flying, more hours on each than there actually are etc.) > > > > I feel confident that if there is a design flaw Zenith will address the issue appropriately, hopefully the wreckage is in such condition that it can yield better information than the other wrecks that were inconclusive due to post crash fire. Hopefully the landing in the ocean in relatively shallow waters will allow for a more conclusive investigation. My thoughts and prayers go out to the families. > > > > If only one good thing comes of this accident, please let it be that IF there is a design issue, that it can be addressed. > > > > -------- > > One Rivet at a Time! > > > > > > > > > > Read this topic online here: > > > > http://forums.matronics.com/viewtopic.php?p=168995#168995 > > > > > > > > > > > > > > > > > > > > > > > > > > > -------- One Rivet at a Time! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169021#169021 ________________________________ Message 18 ____________________________________ Time: 08:52:55 AM PST US Subject: Zenith-List: Re: Accident From: "ashontz" Considering it's an eye-witness account, can they really be sure they saw the explosion first. Most people I know who are pilots don't watch planes overhead like pilots do. They'd only look up if something odd happened, like they heard a loud bang that actually occured 2.5 seconds beforehand, then they look up and see a plane with it's wing folded up, therefore, to the unwashed masses that means, loud bang, THEN wing fold. MHerder wrote: > John, > > Regarding Note 1. I concur, (this incident seems to have the most plausible explanation, simply flying in adverse conditions). However, you mention that "a lot of cases" of wing failures can be found in certified aircraft. I was quite surprised to find how few there really were. Perhaps my search parameters could be tight but when searching key words like wing failure, in flight break up etc not too many come up. > > Note 2 > > Yes a bird strike is certainly a possibility, Mythbusters has some dramatic showing videos that show the potential damage from a bird strike. A million things COULD have happened, but there appears to be a common thread in witness descriptions. Yes, I agree I wouldn't bet two cents on a witnesses ability to truly give the type of information necessary to actually find cause. However, all of the accounts seem to be consistent. Loud bang, wing fold, spiral to ground. > > > johnd(at)data-tech.com wrote: > > Hi Michael, > > > > As a 601XL builder I too am concerned but would like to add a couple of > > data points to this discussion: > > > > 1. The accident in Canadian, TX looks like it involved thunderstorms and > > I've read lots of cases of certified aircraft with wings coming off in > > such cases. So I'm not sure we can really point to an unexpected wing > > failure in this case. > > > > 2. The recent Australian case hasn't been show to have been caused by a > > wing failure. I think folks are jumping the gun on this one. What > > strikes me as odd is that they have found pieces of the canopy over land > > which would seem indicate that the canopy was damaged early in the > > accident. The wing apparently wasn't found with this debris. I wonder > > about a bird strike in this one...It will be interesting to see what > > they find when they locate the plane. Apparently thats supposed to > > happen later this week when the bad weather they are having subsides... > > > > > > John Davis > > Burnsville, NC 28714 > > 601XL - Jab 3300 > > > > MHerder wrote: > > > > > > > > > > > Disclaimer: The information contained below is filled with my own personal assumptions, many of which may not be correct (I am only trying to use my best logic) I do not wish to be involved in a flaming session since this is a very touchy subject for those of us (myself included) who truly take pride in their project and enjoy every second of working on their project and have invested a large amount of time and money. I am only trying to ask some questions and get others opinions as to whether or not my assumptions are logical or reasonable. > > > > > > Does anyone know if the incident in Spain and Australia involved the UL version of the XL, or the UL version of the HD. Zenair apparently manufactures the "ultralight" version for the euro market ( I don't know what is required in Australia). As a builder I am deeply concerned, my condolences go out to the families effected. > > > > > > The reason I ask is that the UL version is about 200 or so pounds less (gross weight). I look at the structure of my aircraft under construction and wonder where the hell I could take out such a significant amount of weight without making sacrifices somewhere. (Lighter landing gear seems to be the largest component) > > > > > > I DO NOT believe that Zenith is marketing and selling a dangerous design. Someone once pointed out that all of the significant fly in the XL frequently, which I think is a very valid point. > > > > > > However, I was more easily able to dismiss the first two or so incidents. This latest series is especially bothersome. > > > > > > My searches find 2 down in Cali with apparent wing failures, 1 down in Canadian TX. All of the three point to wing failures, add 2 to it and it brings us up to 5 Zodiac XL's with apparent wing failures. In an approximately 2 or so year span. How many Zodiac XL's are flying? FAA (which only shows registrations for US owned) shows about 225 or so. If we assume ( and this is a giant assumption) that the US market represents 60-70% of all Zodiac flying Zodiac XL's to about 3-400 FLYING Zodiac XL's. Can someone please substantiate or reject these approximations? I don't even consider the HD in these numbers because the wing is an entirely different spar design (we are talking about wing failures not rudder failures) If it were rudder failures I would consider their flying numbers in my figures since they both use the same rudder. > > > > > > What is the average number of hours on each Zodiac XL at this point in time? My guess would be about 150-200. (This is only my wild guess). > > > > > > So is it safe to say that there is 1 wing failure per 15000 hrs flown in a Zodiac XL? If you fly in a Zodiac for 500 hrs do you have an 3.3% chance of experiencing a wing failure? > > > > > > Guys I'm just trying to rattle around some numbers, I think my numbers are conservative. (More zodiacs than there actually are flying, more hours on each than there actually are etc.) > > > > > > I feel confident that if there is a design flaw Zenith will address the issue appropriately, hopefully the wreckage is in such condition that it can yield better information than the other wrecks that were inconclusive due to post crash fire. Hopefully the landing in the ocean in relatively shallow waters will allow for a more conclusive investigation. My thoughts and prayers go out to the families. > > > > > > If only one good thing comes of this accident, please let it be that IF there is a design issue, that it can be addressed. > > > > > > -------- > > > One Rivet at a Time! > > > > > > > > > > > > > > > Read this topic online here: > > > > > > http://forums.matronics.com/viewtopic.php?p=168995#168995 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -------- Andy Shontz CH601XL - Corvair www.mykitlog.com/ashontz Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169023#169023 ________________________________ Message 19 ____________________________________ Time: 09:01:38 AM PST US Subject: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is a picture. From: "Gig Giacona" Andy, witness accounts are horribly bad. If I was charged with murder I'd rather have five eye witnesses testifying against me than one blurry picture of me committing the crime. -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169024#169024 ________________________________ Message 20 ____________________________________ Time: 09:15:09 AM PST US From: Paul Mulwitz Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is a picture. Hi Andy, This is a good question - what could cause an explosion. Indeed, I remember another report of an explosion that seemed to just precede a structural failure. I also remember a report of an engine revving irregularly just before the explosion. Perhaps I am mixing and matching different incidents, but I remember both reports. I would guess the most likely ingredient for an accidental explosion would be loose fuel in the cabin. There really isn't a way you could get a lot of loose fuel in the wing structure since the fuel is stored on the front side of the mostly solid wing spar. I can envision a fuel leak combined with a wing mounted fuel pump that forces a lot of fuel into the cabin. This isn't as likely if the normal fuel pump arrangement is used because a leak would give the pump in the engine compartment just air to suck on rather than fuel. A cabin full of fuel vapor and air combined with a spark of some sort might give a big fuel-air explosion. Please note that the theoretical explosion described above has no basis at all in a structural design or construction issue. It is based on a simple failure in the fuel system combined with an ill-advised arrangement of fuel pumps. As far as I know, there has been no proven wing design problem. I don't know where that idea came from. There have been wing separations, but I can't remember any confirmed explanation as to why that separation occurred. Since Chris Heintz has reexamined and retested the wing structure since the first few structural failures I think it would be foolish to make a major wing design change with the hope of solving a problem. Any major change, like adding ribs, would be just as likely to cause new problems as to solve any old ones. I personally feel there is no point in trying to come up with some mathematical explanation of the accidents with the hope of computing odds of failure of any new plane. This might help you sleep at night, but I don't think it is a valid analysis technique for this kind of problem. There have been several airplane designs in the past that had horrible accident records and structural failures. None of these were random in nature. They were expressions of latent design problems that were eventually identified and fixed. The planes I am thinking of for this point are the V-tail Bonanza and the Lockheed Electra. As for personal decisions, I think everyone considering flying a Zodiac XL (like me) should come to terms with the notion that this is a dangerous activity that could end in disaster. If you can't live with that then you shouldn't be flying this or any other experimental airplane. To pretend that experimental airplanes are anything other than dangerous is just kidding yourself. Paul XL fuselage At 08:16 AM 3/11/2008, you wrote: >What would cause an explosion, leaking fuel tank into the wing >structure? Empty tank that for some reason exploded? ________________________________ Message 21 ____________________________________ Time: 09:27:07 AM PST US From: alex trent Subject: Zenith-List: accident Looking at the photo, at this link, it appears that both wings are still attached??????????? Time: 01:47:19 PM PST US From: William Dominguez Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is a picture. I found this from from the accident page of ultraligero.net, the entry is at the bottom: http://www.ultraligero.net/Accidentes/08.htm ________________________________ Message 22 ____________________________________ Time: 09:32:20 AM PST US From: Debo Cox Subject: Re: Zenith-List: Re: XL - success stories Hey guys! The only snobbishness I've encountered was from people who either didn't understand the design or prefer something different. It's like guitar players - you either like Fenders or Gibsons. Both are great guitars. I made the decision that was right for me - not somebody else, so I really don't care what they think. I did a lot of research before making my choice. I trust the design and the designer or I wouldn't be building it. My trust extends to knowing that if a problem surfaces, a proper and acceptable solution will be offered. Until then, I'm dancing with the one that brung me. Now get off the computer and go pull some rivets. Debo Cox Nags Head, NC www.mykitlog.com/debo do not archive ________________________________ Message 23 ____________________________________ Time: 09:32:27 AM PST US Subject: Zenith-List: Re: Fuel Pump & Gascolator For Sale From: "ricklach" Hi Andy, I would like to buy your fuel pump, Rick rick@ravengear.us Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169030#169030 ________________________________ Message 24 ____________________________________ Time: 09:53:28 AM PST US From: Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is a picture. While the loud bang was heard and a falling twisting mass was see does not necessarily mean something exploded. Has anyone here see a wing tested to failure? I have see a 747, 727, Cessna 310, 210 and 150 wing tested to failure......when they finaly failed, it was a very surpisingly loud bang. What the witnesses heard could have just been the structual failure......The one thing I never saw in the reports were evidence of a fire in the air or witnesses seeing a smoke trail to the ground. David Mikesell Cloverdale, CA 95425 ----- Original Message ----- From: "Paul Mulwitz" Sent: Tuesday, March 11, 2008 9:12 AM Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is a picture. > > Hi Andy, > > This is a good question - what could cause an explosion. Indeed, I > remember another report of an explosion that seemed to just precede a > structural failure. I also remember a report of an engine revving > irregularly just before the explosion. Perhaps I am mixing and matching > different incidents, but I remember both reports. > > I would guess the most likely ingredient for an accidental explosion would > be loose fuel in the cabin. There really isn't a way you could get a lot > of loose fuel in the wing structure since the fuel is stored on the front > side of the mostly solid wing spar. > > I can envision a fuel leak combined with a wing mounted fuel pump that > forces a lot of fuel into the cabin. This isn't as likely if the normal > fuel pump arrangement is used because a leak would give the pump in the > engine compartment just air to suck on rather than fuel. A cabin full of > fuel vapor and air combined with a spark of some sort might give a big > fuel-air explosion. > > Please note that the theoretical explosion described above has no basis at > all in a structural design or construction issue. It is based on a simple > failure in the fuel system combined with an ill-advised arrangement of > fuel pumps. > > As far as I know, there has been no proven wing design problem. I don't > know where that idea came from. There have been wing separations, but I > can't remember any confirmed explanation as to why that separation > occurred. Since Chris Heintz has reexamined and retested the wing > structure since the first few structural failures I think it would be > foolish to make a major wing design change with the hope of solving a > problem. Any major change, like adding ribs, would be just as likely to > cause new problems as to solve any old ones. > > I personally feel there is no point in trying to come up with some > mathematical explanation of the accidents with the hope of computing odds > of failure of any new plane. This might help you sleep at night, but I > don't think it is a valid analysis technique for this kind of problem. > There have been several airplane designs in the past that had horrible > accident records and structural failures. None of these were random in > nature. They were expressions of latent design problems that were > eventually identified and fixed. The planes I am thinking of for this > point are the V-tail Bonanza and the Lockheed Electra. > > As for personal decisions, I think everyone considering flying a Zodiac XL > (like me) should come to terms with the notion that this is a dangerous > activity that could end in disaster. If you can't live with that then you > shouldn't be flying this or any other experimental airplane. To pretend > that experimental airplanes are anything other than dangerous is just > kidding yourself. > > Paul > XL fuselage > > > At 08:16 AM 3/11/2008, you wrote: >>What would cause an explosion, leaking fuel tank into the wing structure? >>Empty tank that for some reason exploded? > > > ________________________________ Message 25 ____________________________________ Time: 10:17:06 AM PST US From: "Darrell Haas" Subject: Re: Zenith-List: accident It looked like that to me also. And the trim for the canopy was up. Darrell do not archive On 3/11/08, alex trent wrote: > > Looking at the photo, at this link, it appears that both wings are still attached??????????? > > Time: 01:47:19 PM PST US > From: William Dominguez > Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is > a picture. > > I found this from from the accident page of ultraligero.net, the entry is at the > bottom: > > http://www.ultraligero.net/Accidentes/08.htm > > ________________________________ Message 26 ____________________________________ Time: 10:18:23 AM PST US From: "ella" Subject: Re: Zenith-List: Re: Accident Hi Your numbers may be close. If there has been 5 wing failures in a certain model aircraft I would say there has to be a reason why I have just started my rudder and I am concerned. I can't remember any wing failures in Cessna 172 or 150 but I could wrong ---- Original Message ----- From: "MHerder" Sent: Tuesday, March 11, 2008 12:17 PM Subject: Zenith-List: Re: Accident > > Disclaimer: The information contained below is filled with my own > personal assumptions, many of which may not be correct (I am only trying > to use my best logic) I do not wish to be involved in a flaming session > since this is a very touchy subject for those of us (myself included) who > truly take pride in their project and enjoy every second of working on > their project and have invested a large amount of time and money. I am > only trying to ask some questions and get others opinions as to whether or > not my assumptions are logical or reasonable. > > Does anyone know if the incident in Spain and Australia involved the UL > version of the XL, or the UL version of the HD. Zenair apparently > manufactures the "ultralight" version for the euro market ( I don't know > what is required in Australia). As a builder I am deeply concerned, my > condolences go out to the families effected. > > The reason I ask is that the UL version is about 200 or so pounds less > (gross weight). I look at the structure of my aircraft under construction > and wonder where the hell I could take out such a significant amount of > weight without making sacrifices somewhere. (Lighter landing gear seems > to be the largest component) > > I DO NOT believe that Zenith is marketing and selling a dangerous design. > Someone once pointed out that all of the significant fly in the XL > frequently, which I think is a very valid point. > > However, I was more easily able to dismiss the first two or so incidents. > This latest series is especially bothersome. > > My searches find 2 down in Cali with apparent wing failures, 1 down in > Canadian TX. All of the three point to wing failures, add 2 to it and it > brings us up to 5 Zodiac XL's with apparent wing failures. In an > approximately 2 or so year span. How many Zodiac XL's are flying? FAA > (which only shows registrations for US owned) shows about 225 or so. If > we assume ( and this is a giant assumption) that the US market represents > 60-70% of all Zodiac flying Zodiac XL's to about 3-400 FLYING Zodiac XL's. > Can someone please substantiate or reject these approximations? I don't > even consider the HD in these numbers because the wing is an entirely > different spar design (we are talking about wing failures not rudder > failures) If it were rudder failures I would consider their flying numbers > in my figures since they both use the same rudder. > > What is the average number of hours on each Zodiac XL at this point in > time? My guess would be about 150-200. (This is only my wild guess). > > So is it safe to say that there is 1 wing failure per 15000 hrs flown in a > Zodiac XL? If you fly in a Zodiac for 500 hrs do you have an 3.3% chance > of experiencing a wing failure? > > Guys I'm just trying to rattle around some numbers, I think my numbers are > conservative. (More zodiacs than there actually are flying, more hours on > each than there actually are etc.) > > I feel confident that if there is a design flaw Zenith will address the > issue appropriately, hopefully the wreckage is in such condition that it > can yield better information than the other wrecks that were inconclusive > due to post crash fire. Hopefully the landing in the ocean in relatively > shallow waters will allow for a more conclusive investigation. My > thoughts and prayers go out to the families. > > If only one good thing comes of this accident, please let it be that IF > there is a design issue, that it can be addressed. > > -------- > One Rivet at a Time! > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=168995#168995 > > > ________________________________ Message 27 ____________________________________ Time: 10:20:57 AM PST US Subject: Zenith-List: Re: Accident From: "ashontz" I'm starting to think the main culprit here, if there is in fact wing folding incidents not due to pulling to hard on the elevator, is torsional strength of the wing and under certain conditions turns into abrupt wing flutter. I'm even inclined to think that the slight forward sweep really doesn't have much to do with it, although it's not helping, but is not the main culprit. Consider every time a true straight wing plane is slipped, well, right there you have forward sweep on ne wing. Any time the ball is not perfectly centered, again, one wing or the other is experiencing forward sweep. I think one condition that could lead to a wing folding in the XL would be, deploy flaps, then turn, then either drop the nose or raise the nose. Say it's a left turn. More than likely the ball will not be perfectly centered, and due to adverse yaw, now the left wing will be even more 'forward swept'. So now we've got a wing in preloaded in maximum torsion, flap down, elevator up, possibly wing even more forward swept due to adverse yaw, and you either drop the nose or rais the nose somewhat abruptly adding to or descreasing the torsional spiring loading of the wing. If the wing is not reinforced enough it starts to go into aero-elastic flutter, which if the rivets aren't good, we've already got a forward canted spar, and you have a wing locker giving even less buckling resistance to the main spar between rib 4 and 5, well, that might not be too fun to experience. But it all starts with torsional resistance. -------- Andy Shontz CH601XL - Corvair www.mykitlog.com/ashontz Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169042#169042 ________________________________ Message 28 ____________________________________ Time: 10:21:36 AM PST US From: Juan Vega Subject: Re: Zenith-List: Re: XL - success stories Here is my question to all on accidents, the design has been around for a while. How many years has the number of planes been around, 1992? and how many accidents total, compared to Vans RV and their total accidents? WHat I am getting at is the plane design is historically sound, the pilots are the issue or the builder. Its always hard to look in the mirror and point the fingure at what we see looking back. Most of the guys that own an RV that I take flying in my 601 are frankly asking me whether I want a partner in my plane. The 601xl is a great plane. If you try to fly it like an RV, then you will have issues. Juan -----Original Message----- >From: pavel569 >Sent: Mar 10, 2008 11:31 PM >To: zenith-list@matronics.com >Subject: Zenith-List: Re: XL - success stories > > >The problem is - you'll never see an article in a newspaper about a "guy who fly his Zodiac XL for so many hours without any problem". People just want to see a debris on the ground that not a long ago use to be an airplane. It just a nature of ours, I guess. If there is a problem with either an airframe rigidity or material weakness, there would be hundreds of 601's in scrap metal junkyards and hundreds of gravestones with pilots names on them. There is a few, of course. But the reason can be over stressing the airframe by rough pilotage, lack of craftsmanship or compromising quality when building. If we fly the Zodiac as it is a Cherokee, not trying to get closer to critical loads, I think we will be fine. Big words for a guy who will (hopefully) get his private license next month, right? But I don't think that anyone who builds and/or fly wants to kill himself. Just be friend to your plane, don't twist her hands, don't bent her neck and she will be a good friend of yours ! > too. > >-------- >Pavel >CA >Zodiac XL N581PM (Reserved) > > >Read this topic online here: > >http://forums.matronics.com/viewtopic.php?p=168941#168941 > > ________________________________ Message 29 ____________________________________ Time: 10:46:15 AM PST US From: Kevin Bonds Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is a picture. I downloaded the photo and enlarged it. What is weird, to me, is that the wings seem to be beat-all-to-hell but the horizontal stabilizer is pristine. You can clearly see it in the background. Best I can tell, is that the plane is on its (left?) side with both wings folded against the canopy. I think I'm seeing both spars exposed with the leading edges missing or crumpled. That horizontal stab doesn't look like it has a scratch on it! Also, I am trying to make out the objects below the right wheel that is sticking up in the air. Could those be noseribs? Looks like a lot of twisted sheet metal around the right wing but there doesn't seem to be as much crumpled stuff around the left. The left spar seems to be stripped more cleanly. I hate the idea of armchair aircraft engineering. But, I've always believed that the point of failure would have to be the leading edge skin along the spar. That's why I don't consider adding extra ribs to the wings to be of any use unless we're talking nose ribs. I've spoken to another XL builder friend about this many times in the past after one of these accidents. What spotty information, we have had, suggests that the spar rivet line is, or would have to be, the point of failure for the wing to fold--either in flight or on impact. I would think that the nose skin would have to unzip--on top or maybe bottom--before the wing would fold up. It appears that the bottom main wing skin is loose on the right wing in this photo. I see a waviness/buckling above the spar. Not saying the design is flawed. Every structure has a point of failure, no matter how strong. Kevin Bonds ashontz wrote: > > Didn't one of the others have it's wings break off AFTER an explosion? ________________________________ Message 30 ____________________________________ Time: 10:50:33 AM PST US From: "Iberplanes IGL" Subject: Re: Zenith-List: accident Absolutely right, both wings were attached. Apparently they went beyond VNE. Still waiting the final report. The canopy was found 150 mts away from the plane, in the middle of a town. Many witness said theyve heard and explosion (probably the canopy) followed by a plane falling on an spiral. (Sorry, my English in this case sucks) ----- Original Message ----- From: "alex trent" Sent: Tuesday, March 11, 2008 5:23 PM Subject: Zenith-List: accident > > Looking at the photo, at this link, it appears that both wings are still > attached??????????? > > Time: 01:47:19 PM PST US > From: William Dominguez > Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and > there is > a picture. > > I found this from from the accident page of ultraligero.net, the entry is > at the > bottom: > > http://www.ultraligero.net/Accidentes/08.htm > > > ________________________________ Message 31 ____________________________________ Time: 10:55:12 AM PST US From: "Iberplanes IGL" Subject: Re: Zenith-List: Re: Accident in Spain Right, thats the plane and people I=B4m talking about. ----- Original Message ----- From: William Dominguez To: zenith-list@matronics.com Sent: Monday, March 10, 2008 3:56 PM Subject: Re: Zenith-List: Re: Accident in Spain Are you refering to this accident?: http://www.elpais.com/articulo/cataluna/muertos/estrellarse/avioneta/vine do/Subirats/elpepiespcat/20080206elpcat_28/Tes The news doesn't mention make and model but it is about an 2 place aircraft that apparently lost a wing in flight. William Dominguez Zodiac 601XL Plans Miami, Florida http://www.geocities.com/bill_dom Iberplanes IGL wrote: We had an 601 XL down in Barcelona 2 month ago. Aparently, wing fold. 2008/3/10, Iberplanes IGL : Si es por un ala, me comienza a preocupar. Voy a investigar y te cuento. saludos ---------- Forwarded message ---------- From: ashontz Date: 10-mar-2008 12:55 Subject: Zenith-List: Re: Accident To: zenith-list@matronics.com Regardless, I'm adding extra ribs, going with the 12 gallon tanks instead of the 15, no wing-locker, and some sort of overridable system that limits control surface/stick travel at and above manuevering speed. Kevin Bonds wrote: > Andy, > > Let's not jump to any conclusions here. Sounds more like there may have > been a problem with the canopy, if I had to guess--which we shouldn't. I > know an eyewitness stated that a wing /may/ have come off, but I doubt > many eyewitnesses would know a wing from a rudder or any other part in > that instance. Hopefully they will recover the plane. The wings could, > very well, still be intact. Sounds like the canopy will not be since > they found 3 pieces of it scattered on shore. The plane was supposed to > have gone-in 700 meters from shore. > > Kevin Bonds > > ashontz wrote: > > > > > > > Thanks. > > > > Thoe extra wings ribs are looking better and better all the time. > > > > > > > > > > > ________________________________ Message 32 ____________________________________ Time: 11:02:13 AM PST US From: John Davis Subject: Re: Zenith-List: Re: Accident Hi, Here's a C150 that lost both its wings last year in Virginia : http://ntsb.gov/ntsb/brief.asp?ev_id 060917X01355&key=1. Scott Crossfields Cessna 210 also experienced an in flight breakup due to WX: http://ntsb.gov/ntsb/brief.asp?ev_id 060501X00494&key=1 and a 172 in GA that brokeup: http://ntsb.gov/ntsb/brief.asp?ev_id 030325X00386&key=1 And there are more if you look at the ntsb.gov database. I know its easy to get all hyped up with conjecture about these accidents but its important to stick with the facts that we have as well. Certificated aircraft do have accidents involving in-flight breakups, some due to pilot's overstressing the airframe, weather induced failures, shear stupidity on the pilots part, etc. I do wish we really had some facts in the 601XL cases so we could put this whole issue to rest one way or the other. John ella wrote: > > Hi > Your numbers may be close. If there has been 5 wing failures in a > certain model aircraft I would say there has to be a reason why > I have just started my rudder and I am concerned. I can't > remember any wing failures in Cessna 172 or 150 but I could wrong > ---- Original Message ----- From: "MHerder" > To: > Sent: Tuesday, March 11, 2008 12:17 PM > Subject: Zenith-List: Re: Accident > > >> >> >> Disclaimer: The information contained below is filled with my own >> personal assumptions, many of which may not be correct (I am only >> trying to use my best logic) I do not wish to be involved in a >> flaming session since this is a very touchy subject for those of us >> (myself included) who truly take pride in their project and enjoy >> every second of working on their project and have invested a large >> amount of time and money. I am only trying to ask some questions and >> get others opinions as to whether or not my assumptions are logical >> or reasonable. >> >> Does anyone know if the incident in Spain and Australia involved the >> UL version of the XL, or the UL version of the HD. Zenair apparently >> manufactures the "ultralight" version for the euro market ( I don't >> know what is required in Australia). As a builder I am deeply >> concerned, my condolences go out to the families effected. >> >> The reason I ask is that the UL version is about 200 or so pounds >> less (gross weight). I look at the structure of my aircraft under >> construction and wonder where the hell I could take out such a >> significant amount of weight without making sacrifices somewhere. >> (Lighter landing gear seems to be the largest component) >> >> I DO NOT believe that Zenith is marketing and selling a dangerous >> design. Someone once pointed out that all of the significant fly in >> the XL frequently, which I think is a very valid point. >> >> However, I was more easily able to dismiss the first two or so >> incidents. This latest series is especially bothersome. >> >> My searches find 2 down in Cali with apparent wing failures, 1 down >> in Canadian TX. All of the three point to wing failures, add 2 to it >> and it brings us up to 5 Zodiac XL's with apparent wing failures. In >> an approximately 2 or so year span. How many Zodiac XL's are >> flying? FAA (which only shows registrations for US owned) shows >> about 225 or so. If we assume ( and this is a giant assumption) that >> the US market represents 60-70% of all Zodiac flying Zodiac XL's to >> about 3-400 FLYING Zodiac XL's. Can someone please substantiate or >> reject these approximations? I don't even consider the HD in these >> numbers because the wing is an entirely different spar design (we are >> talking about wing failures not rudder failures) If it were rudder >> failures I would consider their flying numbers in my figures since >> they both use the same rudder. >> >> What is the average number of hours on each Zodiac XL at this point >> in time? My guess would be about 150-200. (This is only my wild >> guess). >> >> So is it safe to say that there is 1 wing failure per 15000 hrs flown >> in a Zodiac XL? If you fly in a Zodiac for 500 hrs do you have an >> 3.3% chance of experiencing a wing failure? >> >> Guys I'm just trying to rattle around some numbers, I think my >> numbers are conservative. (More zodiacs than there actually are >> flying, more hours on each than there actually are etc.) >> >> I feel confident that if there is a design flaw Zenith will address >> the issue appropriately, hopefully the wreckage is in such condition >> that it can yield better information than the other wrecks that were >> inconclusive due to post crash fire. Hopefully the landing in the >> ocean in relatively shallow waters will allow for a more conclusive >> investigation. My thoughts and prayers go out to the families. >> >> If only one good thing comes of this accident, please let it be that >> IF there is a design issue, that it can be addressed. >> >> -------- >> One Rivet at a Time! >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=168995#168995 >> >> >> >> >> >> >> >> >> >> >> > > ________________________________ Message 33 ____________________________________ Time: 11:05:44 AM PST US From: "Randy" Subject: Re: Zenith-List: accident There are two photos in that attachment. This first one is not a 601xl, the airfoil is much thinner than an XL. Randy ----- Original Message ----- From: "Darrell Haas" Sent: Tuesday, March 11, 2008 12:13 PM Subject: Re: Zenith-List: accident > > It looked like that to me also. And the trim for the canopy was up. > Darrell > do not archive > > On 3/11/08, alex trent wrote: >> >> Looking at the photo, at this link, it appears that both wings are still >> attached??????????? >> >> Time: 01:47:19 PM PST US >> From: William Dominguez >> Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and >> there is >> a picture. >> >> I found this from from the accident page of ultraligero.net, the entry >> is at the >> bottom: >> >> http://www.ultraligero.net/Accidentes/08.htm >> >> >> >> >> >> > > > ________________________________ Message 34 ____________________________________ Time: 11:08:29 AM PST US Subject: Zenith-List: Re: XL - success stories From: "swater6" Based on a quick FAA database query, there are 239 601 XL success stories in the USA today!!! There are 51 AMD XL's, 2 CAW XL's and 185 AB Experimental XL's. And too many more HD's and HDS's to count. I'm working hard to add mine to the list! Scott -------- 601 XL kit N596SW reserved Tail, control surfaces and both wings complete. Now working on fuselage www.scottwaters.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169057#169057 ________________________________ Message 35 ____________________________________ Time: 11:25:43 AM PST US From: William Dominguez Subject: Re: Zenith-List: accident It looks like the plane is resting on the left side of the fuselage with both wings folded up in relation to the plane. The leading edge skin seem to be missing from the most part exposing the main spar. Strangely enough, the stabilizer an elevator can be seen intact in a vertical position in the background. The front wheel is pointing to the left side. Something to keep in mind about this accident is that some of the news that cover it didn't mention a wing failure but an engine failure as the cause. William Dominguez Zodiac 601XL Plans Miami Florida http://www.geocities.com/bill_dom It looked like that to me also. And the trim for the canopy was up. Darrell do not archive On 3/11/08, alex trent wrote: > > Looking at the photo, at this link, it appears that both wings are still attached??????????? > > Time: 01:47:19 PM PST US > From: William Dominguez > Subject: Re: Zenith-List: Re: Accident in Spain was a Zodiac 601XL and there is > a picture. > > I found this from from the accident page of ultraligero.net, the entry is at the > bottom: > > http://www.ultraligero.net/Accidentes/08.htm > > ________________________________ Message 36 ____________________________________ Time: 11:46:51 AM PST US From: "Iberplanes IGL" Subject: Zenith-List: 601 XL Down in Barcelona Hi there The 601 XL down in Barcelona, was a kit wich parts were made at the Czech Republic, built many years ago. Was no the "european version" as said on the list. The canopy was found 150 meters away, there are rumors everywere and I=B4m trying to contact the investigators, because I like to know what really happened. Both pilots were very well known at the aerodrome where i=B4m flying. Was a great loss. Take care, Alberto Martin Iberplanes IGL http://www.iberplanes.es Igualada - Barcelona - Espa=F1a ________________________________ Message 37 ____________________________________ Time: 11:52:00 AM PST US Subject: Zenith-List: Re: Accident From: "swater6" OK, I hate these accident discussions because they are full of conjecture, assumptions, false information and all sorts of wild guesses from people who know little or nothing. The more we talk about "what-ifs' and possible design flaws the more scared we get and scared is not good. We are pilots and we should mitigate risk to the best of our ability and accept the rest or don't fly. So, as builders we do the same. I mitigated risk by choosing an airframe and engine design with many examples flying from a designer and company with excellent history. I accept the other risks that I cannot control. Now, hearing about accidents makes us take notice. We should take notice so that we can learn from them if possible. Clearly, it seems unusually to hear more than one structural failure and we want to know if it was the pilot or the design. Personally, I haven't seen enough evidence to make me scrap my 75% completed airplane. But, for those of you that are new or just forgot, below are the facts from the FAA and NTSB databases. You can look them up if you want. As of today, there are 239 registered 601 XL's in the United States. -51 are made by AMD -3 are made by CAW -185 are amateur built In the last 2 years, there have been 5 (FIVE) fatal accidents: 11/2/07- 1st flight AB-Exp. on take-off rolled left into terrain. 5/2/07-In flight break-up. AB-Exp 1 year sport pilot flew into IMC in heavy rain and possible convective activity (ie thundersorm) 11/11/06- CAW SLW- Fuel exhaustion (empty tanks) flew into trees 11/4/06-AMD In flight break-up. 2/8/06-AB-Exp first flight by new owner and CFI. NTSB probable cause: Structural failure of wing for unknown reasons. (This is the accident that prompted the additional wing testing for positive G's and the letter from Chris Hientz warning pilots of abrupt full elevator deflection) Now, my advise to myself until I know more is to realize this: The XL flies about as fast as the 172 I fly and weighs half as much. It is a "light" sport plane and when I fly it, I will fly it carefully and well within the normal envelope. I'll put gas in it, I won't fly into thunderstorms, I will get transition training and I will maintain it to the highest standards. That's it, my lunch hour is over....carry on...... Scott PS, I don't know how many RV's there are registered but 27 fatal accidents in the same period with one wing falure... -------- 601 XL kit N596SW reserved Tail, control surfaces and both wings complete. Now working on fuselage www.scottwaters.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169066#169066 ________________________________ Message 38 ____________________________________ Time: 11:57:28 AM PST US From: "Bob McArdle" Subject: Zenith-List: Skins Do the rear and middle top skins overlap or go inside the side skins? ________________________________ Message 39 ____________________________________ Time: 12:04:18 PM PST US From: "tlski" Subject: Re: Zenith-List: Re: XL - success stories The EAA group in in my area is mostly RV's, our pres is part of a formation group of RV's, but they done look down on the rest of us. We have a 601xl, mine, 701 , 601HD and a 801 along with host of others. I chose the 601xl because of the time to build but also becuase I would like my wife to get her Sport License. The 601xl is a comforable and easy plane to fly, but like any aircraft you must respect it. Saving for wings Tom ----- Original Message ----- From: "John Bolding" Sent: Tuesday, March 11, 2008 11:11 AM Subject: Re: Zenith-List: Re: XL - success stories > > > Isn't it strange! When I built my RV3 about a hundred yrs ago it was > like the Zenith group is now, bunch of guys building airplanes and having > a good time, nobody had their nose in the air. Was at a fly-in (Texas) a > month ago and a fellow with a fresh RV6 had his chest stuck way out and > asked smugly if I ever thought about building an RV, answer was "Yep, > built the second RV to fly in Texas before you were born". I'm a little > abrasive sometimes. > Hopefully the Zenith crowd doesn't get that way. Not all the RV guys are > like that but there ARE a bunch of them. > LO&SLO John > > > ----- Original Message ----- > From: "Darrell Haas" > To: > Sent: Tuesday, March 11, 2008 9:18 AM > Subject: Re: Zenith-List: Re: XL - success stories > > >> >> YES! All of my EAA group are Van's builders and they really let you know >> it. >> Darrell >> 601XL >> do not archive >> >> On 3/11/08, PatrickW wrote: >>> >>> Do you guys ever feel like you have to defend the Zodiac when talking >>> to builders of other airplanes? >>> >>> Patrick >>> XL/Corvair >>> >>> >>> >>> >>> Read this topic online here: >>> >>> http://forums.matronics.com/viewtopic.php?p=168971#168971 >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >> >> >> >> >> >> > > > ________________________________ Message 40 ____________________________________ Time: 12:11:19 PM PST US From: "Craig Payne" Subject: RE: Zenith-List: Re: XL - success stories > Do you guys ever feel like you have to defend the Zodiac when talking to builders of other airplanes? Nope, they say "Zenith? Never heard of it" -- Craig Do not archive ________________________________ Message 41 ____________________________________ Time: 12:32:40 PM PST US Subject: Zenith-List: Re: Skins From: "eddies" The skins overlap Regards, Eddie Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169074#169074 ________________________________ Message 42 ____________________________________ Time: 12:58:38 PM PST US From: Kevin Bonds Subject: Re: Zenith-List: 601 XL Down in Barcelona Thanks Alberto. Keep us posted. The Australian crash was similar. Canopy pieces found far from crash site. Iberplanes IGL wrote: > Hi there > > The 601 XL down in Barcelona, was a kit wich parts were made at the > Czech Republic, built many years ago. Was no the "european version" as > said on the list. > ________________________________ Message 43 ____________________________________ Time: 01:01:42 PM PST US From: frank forgues Subject: RE: Zenith-List: Skins I'm at that stage now and I believe that just like the rudder, the skins ar e positioned inside the panels to mark and drill out matching holes and the n pulled out and repositioned on top of the panels. If they were left insid e, the top edge of the panel would create a lip and capture rain, dew etc.. . which could eventually create corrosion. Hope this helps. Re: rmacpunk@netzero.net wrote... "Do the rear and middle top skins over lap or go inside the side skins?" Frank Forgues fuse 601xl/corvair Toronto Can. From: rmacpunk@netzero.netTo: zenith-list@matronics.comSubject: Zenith-List : SkinsDate: Tue, 11 Mar 2008 14:55:00 -0400 Do the rear and middle top skins overlap or go inside the side skins? _________________________________________________________________ Spread the Love by installing 30 free Messenger Emoticons. Get them now! http://g.msn.ca/ca55/212 ________________________________ Message 44 ____________________________________ Time: 01:11:08 PM PST US Subject: Zenith-List: Re: Accident From: "n85ae" Actually when I think about the way the zenith wings are designed it seems obvious with just a pure positive or negative loading that the wing is plenty strong. However if for some reason you could get it to twist I can imagine how it could collapse and fold back quite easily. Like somebody said this is nothing but pure speculation anyway. Jeff ashontz wrote: > I'm starting to think the main culprit here, if there is in fact wing folding incidents not due to pulling to hard on the elevator, is torsional strength of the wing and under certain conditions turns into abrupt wing flutter. I'm even inclined to think that the slight forward sweep really doesn't have much to do with it, although it's not helping, but is not the main culprit. Consider every time a true straight wing plane is slipped, well, right there you have forward sweep on ne wing. Any time the ball is not perfectly centered, again, one wing or the other is experiencing forward sweep. > > I think one condition that could lead to a wing folding in the XL would be, deploy flaps, then turn, then either drop the nose or raise the nose. Say it's a left turn. More than likely the ball will not be perfectly centered, and due to adverse yaw, now the left wing will be even more 'forward swept'. So now we've got a wing in preloaded in maximum torsion, flap down, aileron up, possibly wing even more forward swept due to adverse yaw, and you either drop the nose or rais the nose somewhat abruptly adding to or descreasing the torsional spiring loading of the wing. If the wing is not reinforced enough it starts to go into aero-elastic flutter, which if the rivets aren't good, we've already got a forward canted spar, and you have a wing locker giving even less buckling resistance to the main spar between rib 4 and 5, well, that might not be too fun to experience. But it all starts with torsional resistance. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169081#169081 ________________________________ Message 45 ____________________________________ Time: 01:12:13 PM PST US From: Larry H Subject: Re: Zenith-List: Re: Accident Thanks Scott for the snap back to reality. It DOES tend to work on one's brain when you hear so much gloom and doom. Flight IS inherently dangerous. So is crossing the street and driving a car or riding in one. I for one take a lot of what I read as simply "information". If I didn't, I would be staying home an awfully lot.......and selling my XL immediately, then going back to bed so I don't risk hurting myself by going up and down my stairs to work on the Zodiac. Thanks for the reality check - I think we all needed it. Larry H swater6 wrote: OK, I hate these accident discussions because they are full of conjecture, assumptions, false information and all sorts of wild guesses from people who know little or nothing. The more we talk about "what-ifs' and possible design flaws the more scared we get and scared is not good. We are pilots and we should mitigate risk to the best of our ability and accept the rest or don't fly. So, as builders we do the same. I mitigated risk by choosing an airframe and engine design with many examples flying from a designer and company with excellent history. I accept the other risks that I cannot control. Now, hearing about accidents makes us take notice. We should take notice so that we can learn from them if possible. Clearly, it seems unusually to hear more than one structural failure and we want to know if it was the pilot or the design. Personally, I haven't seen enough evidence to make me scrap my 75% completed airplane. But, for those of you that are new or just forgot, below are the facts from the FAA and NTSB databases. You can look them up if you want. As of today, there are 239 registered 601 XL's in the United States. -51 are made by AMD -3 are made by CAW -185 are amateur built In the last 2 years, there have been 5 (FIVE) fatal accidents: 11/2/07- 1st flight AB-Exp. on take-off rolled left into terrain. 5/2/07-In flight break-up. AB-Exp 1 year sport pilot flew into IMC in heavy rain and possible convective activity (ie thundersorm) 11/11/06- CAW SLW- Fuel exhaustion (empty tanks) flew into trees 11/4/06-AMD In flight break-up. 2/8/06-AB-Exp first flight by new owner and CFI. NTSB probable cause: Structural failure of wing for unknown reasons. (This is the accident that prompted the additional wing testing for positive G's and the letter from Chris Hientz warning pilots of abrupt full elevator deflection) Now, my advise to myself until I know more is to realize this: The XL flies about as fast as the 172 I fly and weighs half as much. It is a "light" sport plane and when I fly it, I will fly it carefully and well within the normal envelope. I'll put gas in it, I won't fly into thunderstorms, I will get transition training and I will maintain it to the highest standards. That's it, my lunch hour is over....carry on...... Scott PS, I don't know how many RV's there are registered but 27 fatal accidents in the same period with one wing falure... -------- 601 XL kit N596SW reserved Tail, control surfaces and both wings complete. Now working on fuselage www.scottwaters.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169066#169066 --------------------------------- Never miss a thing. Make Yahoo your homepage. ________________________________ Message 46 ____________________________________ Time: 01:18:01 PM PST US From: Larry H Subject: Re: Zenith-List: accident If it was an engine failure, the plane wouldn't be plunging to the ground nose down unless the pilot lost all his airspeed and stalled it out. My question is, if there was a strike on the canopy and its destroyed, how does that change the characteristics of the airfoil and its ability to provide lift? Is there such a thing as a stronger, more durable canopy available than what is provided in the kit?? If so, I would be very interested in purchasing one of them. Things to ponder Larry H William Dominguez wrote: It looks like the plane is resting on the left side of the fuselage with both wings folded up in relation to the plane. The leading edge skin seem to be missing from the most part exposing the main spar. Strangely enough, the stabilizer an elevator can be seen intact in a vertical position in the background. The front wheel is pointing to the left side. Something to keep in mind about this accident is that some of the news that cover it didn't mention a wing failure but an engine failure as the cause. William Dominguez Zodiac 601XL Plans Miami Florida http://www.geocities.com/bill_dom It looked like that to me also. And the trim for the canopy was up. Darrell do not --------------------------------- ________________________________ Message 47 ____________________________________ Time: 01:49:14 PM PST US From: Kevin Bonds Subject: Re: Zenith-List: Re: Accident Scott, You state conclusions about these accidents. But the FAA reports do not do so. So you are making conjectures and assumptions to some extent. So far, the "wild guesses" that have been made, have been made without stating them as facts. I think everyone is prefacing there opinions as such. The point of my last email, was to present an argument against armchair engineering. There is going to be some misstatements and misunderstandings. I think that is par for the course. But at this point, I don't think we should avoid the discussion entirely. I'm ashamed to say that I have been inclined, in the past, to let misstatements, on this list, go unchecked, just because I didn't want to be the one to open the flood gates. This is bad on my part. I'm never sure when to comment and when not too. Someone always seems to complain when you do, but sometimes its necessary. Kevin Bonds swater6 wrote: > > OK, I hate these accident discussions because they are full of conjecture, assumptions, false information and all sorts of wild guesses from people who know little or nothing. The more we talk about ________________________________ Message 48 ____________________________________ Time: 01:49:54 PM PST US From: "Iberplanes IGL" Subject: Re: Zenith-List: accident This is a link to the video of the accident. When this articule was published they suspected an engine failure. At the end of the video you can see the nose wheel. http://www.elmundo.es/elmundo/2008/02/05/barcelona/1202234945.html Alberto Martin Iberplanes IGL http://www.iberplanes.es Igualada - Barcelona - Espa=F1a ----- Original Message ----- From: Larry H To: zenith-list@matronics.com Sent: Tuesday, March 11, 2008 9:15 PM Subject: Re: Zenith-List: accident If it was an engine failure, the plane wouldn't be plunging to the ground nose down unless the pilot lost all his airspeed and stalled it out. My question is, if there was a strike on the canopy and its destroyed, how does that change the characteristics of the airfoil and its ability to provide lift? Is there such a thing as a stronger, more durable canopy available than what is provided in the kit?? If so, I would be very interested in purchasing one of them. Things to ponder Larry H William Dominguez wrote: It looks like the plane is resting on the left side of the fuselage with both wings folded up in relation to the plane. The leading edge skin seem to be missing from the most part exposing the main spar. Strangely enough, the stabilizer an elevator ________________________________ Message 49 ____________________________________ Time: 01:57:00 PM PST US From: "Iberplanes IGL" Subject: Zenith-List: Re: Accident Videos. http://www.atlas-news.com/videos/streaming/adsl/nacional/2008/02/06/video _23021.shtml http://www.youtube.com/watch?v=E_FItiO6Xxc&feature=user Alberto Martin Iberplanes IGL http://www.iberplanes.es Igualada - Barcelona - Espa=F1a ________________________________ Message 50 ____________________________________ Time: 02:35:42 PM PST US From: Kevin Bonds Subject: Re: Zenith-List: accident I noticed that the L angle, where the nose ribs attach, are still attached to the spar, but the ribs are not. Kevin Bonds Iberplanes IGL wrote: > This is a link to the video of the accident. When this articule was > published they suspected an engine failure. > > At the end of the video you can see the nose wheel. > > http://www.elmundo.es/elmundo/2008/02/05/barcelona/1202234945.html > ________________________________ Message 51 ____________________________________ Time: 02:43:18 PM PST US From: Steve Shuck Subject: Re: Zenith-List: accident Wish I spoke and understood Spanish.. Iberplanes IGL wrote: This is a link to the video of the accident. When this articule was published they suspected an engine failure. At the end of the video you can see the nose wheel. http://www.elmundo.es/elmundo/2008/02/05/barcelona/1202234945.html Alberto Martin Iberplanes IGL http://www.iberplanes.es Igualada - Barcelona - Espaa ----- Original Message ----- From: Larry H To: zenith-list@matronics.com Sent: Tuesday, March 11, 2008 9:15 PM Subject: Re: Zenith-List: accident If it was an engine failure, the plane wouldn't be plunging to the ground nose down unless the pilot lost all his airspeed and stalled it out. My question is, if there was a strike on the canopy and its destroyed, how does that change the characteristics of the airfoil and its ability to provide lift? Is there such a thing as a stronger, more durable canopy available than what is provided in the kit?? If so, I would be very interested in purchasing one of them. Things to ponder Larry H William Dominguez wrote: It looks like the plane is resting on the left side of the fuselage with both wings folded up in relation to the plane. The leading edge skin seem to be missing from the most part exposing the main spar. Strangely enough, the stabilizer an elevator href="http://www.matronics.com/Navigator?Zenith-List">http://www.matronhref="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c --------------------------------- ________________________________ Message 52 ____________________________________ Time: 03:35:07 PM PST US Subject: Zenith-List: Re: Accident From: "swater6" Kevin, I meant to paraphrase the content of the NTSB report in my description of each accident. Sorry if it looks as though I was stating a conclusion, I only meant to describe each in a few words based on the content of the NTSB report. Also agreed that we can all give opinions and guesses as we do think these things and wonder. I do get worried when I hear folks talk about modifying a design based on these discussions and sometimes it gets a little out of control. Scott [quote="Kevin Bonds"]Scott, You state conclusions about these accidents. But the FAA reports do not do so. So you are making conjectures and assumptions to some extent. -------- 601 XL kit N596SW reserved Tail, control surfaces and both wings complete. Now working on fuselage www.scottwaters.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169103#169103 ________________________________ Message 53 ____________________________________ Time: 05:02:54 PM PST US Subject: Zenith-List: Re: Accident From: "ashontz" I agree. The wings are plenty strong in static load. Dynamically, I'm not so sure. Extra ribs provide extra torsional stability and strength, as well as actually making the wings stronger in a pure positive or negative load. Shorter segments to transmit the same load across equals less leverage to crumple the skins, particularly in compression. Think of a 5' fishing pole with only one eye at the very end of the pole. Now think of the same pole with an eye every 6 inches. Much stronger under load. I would guess that if you could stand next to that inverted Zenith wing when it was being static tested, and just touched it, it would hobble and bobble all over the place, possibly even notice a bit of a "slow motion flutter". n85ae wrote: > Actually when I think about the way the zenith wings are designed it > seems obvious with just a pure positive or negative loading that the > wing is plenty strong. However if for some reason you could get it to > twist I can imagine how it could collapse and fold back quite easily. > > Like somebody said this is nothing but pure speculation anyway. > > Jeff > > > > ashontz wrote: > > I'm starting to think the main culprit here, if there is in fact wing folding incidents not due to pulling to hard on the elevator, is torsional strength of the wing and under certain conditions turns into abrupt wing flutter. I'm even inclined to think that the slight forward sweep really doesn't have much to do with it, although it's not helping, but is not the main culprit. Consider every time a true straight wing plane is slipped, well, right there you have forward sweep on ne wing. Any time the ball is not perfectly centered, again, one wing or the other is experiencing forward sweep. > > > > I think one condition that could lead to a wing folding in the XL would be, deploy flaps, then turn, then either drop the nose or raise the nose. Say it's a left turn. More than likely the ball will not be perfectly centered, and due to adverse yaw, now the left wing will be even more 'forward swept'. So now we've got a wing in preloaded in maximum torsion, flap down, aileron up, possibly wing even more forward swept due to adverse yaw, and you either drop the nose or rais the nose somewhat abruptly adding to or descreasing the torsional spiring loading of the wing. If the wing is not reinforced enough it starts to go into aero-elastic flutter, which if the rivets aren't good, we've already got a forward canted spar, and you have a wing locker giving even less buckling resistance to the main spar between rib 4 and 5, well, that might not be too fun to experience. But it all starts with torsional resistance. > -------- Andy Shontz CH601XL - Corvair www.mykitlog.com/ashontz Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169110#169110 ________________________________ Message 54 ____________________________________ Time: 05:03:46 PM PST US Subject: Zenith-List: Re: Skins From: "leinad" The top overlaps the side skins, but tucks under the cabin side skins. Leave a large area of the cabin side skins clecoed until you are ready to tuck the top skin under. I'm pretty sure I've got this correct according to the plans (at least the version I purchased). Dan [quote="rmacpunk(at)netzero.net"]Do the rear and middle top skins overlap or go inside the side skins? > [b] -------- Scratch building XL with Corvair Engine Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169111#169111 Attachments: http://forums.matronics.com//files/overlap_145.jpg ________________________________ Message 55 ____________________________________ Time: 05:05:59 PM PST US Subject: Zenith-List: Re: Skins From: "leinad" By the way ignore the date on the photo. I took it a week ago. The battery on my camera died and reset the date. Dan -------- Scratch building XL with Corvair Engine Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169112#169112 ________________________________ Message 56 ____________________________________ Time: 05:13:16 PM PST US From: Gary Gower Subject: Re: Zenith-List: Re: XL - success stories Yep, much like the local BMW motorcycle guys, wearing expensive leather suits :-) Saludos Gary Gower Driving a Black and Chrome Yamaha V Star (Harley look alike). with a "fake leather" jacket :-) Do not archive. John Bolding wrote: Isn't it strange! When I built my RV3 about a hundred yrs ago it was like the Zenith group is now, bunch of guys building airplanes and having a good time, nobody had their nose in the air. Was at a fly-in (Texas) a month ago and a fellow with a fresh RV6 had his chest stuck way out and asked smugly if I ever thought about building an RV, answer was "Yep, built the second RV to fly in Texas before you were born". I'm a little abrasive sometimes. Hopefully the Zenith crowd doesn't get that way. Not all the RV guys are like that but there ARE a bunch of them. LO&SLO John ----- Original Message ----- From: "Darrell Haas" Sent: Tuesday, March 11, 2008 9:18 AM Subject: Re: Zenith-List: Re: XL - success stories > > YES! All of my EAA group are Van's builders and they really let you know > it. > Darrell > 601XL > do not archive > > On 3/11/08, PatrickW wrote: >> >> Do you guys ever feel like you have to defend the Zodiac when talking to >> builders of other airplanes? >> >> Patrick >> XL/Corvair >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=168971#168971 >> >> >> >> >> >> >> >> >> >> >> > > > --------------------------------- ________________________________ Message 57 ____________________________________ Time: 05:18:41 PM PST US From: Gary Gower Subject: Re: Zenith-List: Re: Accident Is like putting a Hummer and a Tracker side by side... :-) Here the C 152 and C 172 can hardly climb, heavyly overbuilt and expensive to fly... As women say around here (for everything they dont like) "I will rather die, than buy one of those" :-) Saludos Gary Gower I think we needed now a little of humor... Too many "experts" around here :-) Do not archive. ella wrote: Hi Your numbers may be close. If there has been 5 wing failures in a certain model aircraft I would say there has to be a reason why I have just started my rudder and I am concerned. I can't remember any wing failures in Cessna 172 or 150 but I could wrong ---- Original Message ----- From: "MHerder" Sent: Tuesday, March 11, 2008 12:17 PM Subject: Zenith-List: Re: Accident > > Disclaimer: The information contained below is filled with my own > personal assumptions, many of which may not be correct (I am only trying > to use my best logic) I do not wish to be involved in a flaming session > since this is a very touchy subject for those of us (myself included) who > truly take pride in their project and enjoy every second of working on > their project and have invested a large amount of time and money. I am > only trying to ask some questions and get others opinions as to whether or > not my assumptions are logical or reasonable. > > Does anyone know if the incident in Spain and Australia involved the UL > version of the XL, or the UL version of the HD. Zenair apparently > manufactures the "ultralight" version for the euro market ( I don't know > what is required in Australia). As a builder I am deeply concerned, my > condolences go out to the families effected. > > The reason I ask is that the UL version is about 200 or so pounds less > (gross weight). I look at the structure of my aircraft under construction > and wonder where the hell I could take out such a significant amount of > weight without making sacrifices somewhere. (Lighter landing gear seems > to be the largest component) > > I DO NOT believe that Zenith is marketing and selling a dangerous design. > Someone once pointed out that all of the significant fly in the XL > frequently, which I think is a very valid point. > > However, I was more easily able to dismiss the first two or so incidents. > This latest series is especially bothersome. > > My searches find 2 down in Cali with apparent wing failures, 1 down in > Canadian TX. All of the three point to wing failures, add 2 to it and it > brings us up to 5 Zodiac XL's with apparent wing failures. In an > approximately 2 or so year span. How many Zodiac XL's are flying? FAA > (which only shows registrations for US owned) shows about 225 or so. If > we assume ( and this is a giant assumption) that the US market represents > 60-70% of all Zodiac flying Zodiac XL's to about 3-400 FLYING Zodiac XL's. > Can someone please substantiate or reject these approximations? I don't > even consider the HD in these numbers because the wing is an entirely > different spar design (we are talking about wing failures not rudder > failures) If it were rudder failures I would consider their flying numbers > in my figures since they both use the same rudder. > > What is the average number of hours on each Zodiac XL at this point in > time? My guess would be about 150-200. (This is only my wild guess). > > So is it safe to say that there is 1 wing failure per 15000 hrs flown in a > Zodiac XL? If you fly in a Zodiac for 500 hrs do you have an 3.3% chance > of experiencing a wing failure? > > Guys I'm just trying to rattle around some numbers, I think my numbers are > conservative. (More zodiacs than there actually are flying, more hours on > each than there actually are etc.) > > I feel confident that if there is a design flaw Zenith will address the > issue appropriately, hopefully the wreckage is in such condition that it > can yield better information than the other wrecks that were inconclusive > due to post crash fire. Hopefully the landing in the ocean in relatively > shallow waters will allow for a more conclusive investigation. My > thoughts and prayers go out to the families. > > If only one good thing comes of this accident, please let it be that IF > there is a design issue, that it can be addressed. > > -------- > One Rivet at a Time! > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=168995#168995 > > > --------------------------------- Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. ________________________________ Message 58 ____________________________________ Time: 05:48:53 PM PST US From: Jaybannist@cs.com Subject: Re: Zenith-List: Re: Accident Or like a Ford Mustang beside a Ford Model A. Jay in Dallas Do not atchive Gary Gower wrote: >Is like putting a Hummer and a Tracker side by side... :-) > > Here the C 152 and C 172 can hardly climb, heavyly overbuilt and expensive to fly... > As women say around here (for everything they dont like) "I will rather die, than buy one of those" :-) > > Saludos > Gary Gower > I think we needed now a little of humor... Too many "experts" around here :-) > Do not archive. > >ella wrote: > >Hi >Your numbers may be close. If there has been 5 wing failures in a certain >model aircraft I would say there has to be a reason why >I have just started my rudder and I am concerned. I can't remember >any wing failures in Cessna 172 or 150 but I could wrong >---- Original Message ----- >From: "MHerder" >To: >Sent: Tuesday, March 11, 2008 12:17 PM >Subject: Zenith-List: Re: Accident > > >> >> Disclaimer: The information contained below is filled with my own >> personal assumptions, many of which may not be correct (I am only trying >> to use my best logic) I do not wish to be involved in a flaming session >> since this is a very touchy subject for those of us (myself included) who >> truly take pride in their project and enjoy every second of working on >> their project and have invested a large amount of time and money. I am >> only trying to ask some questions and get others opinions as to whether or >> not my assumptions are logical or reasonable. >> >> Does anyone know if the incident in Spain and Australia involved the UL >> version of the XL, or the UL version of the HD. Zenair apparently >> manufactures the "ultralight" version for the euro market ( I don't know >> what is required in Australia). As a builder I am deeply concerned, my >> condolences go out to the families effected. >> >> The reason I ask is that the UL version is about 200 or so pounds less >> (gross weight). I look at the structure of my aircraft under construction >> and wonder where the hell I could take out such a significant amount of >> weight without making sacrifices somewhere. (Lighter landing gear seems >> to be the largest component) >> >> I DO NOT believe that Zenith is marketing and selling a dangerous design. >> Someone once pointed out that all of the significant fly in the XL >> frequently, which I think is a very valid point. >> >> However, I was more easily able to dismiss the first two or so incidents. >> This latest series is especially bothersome. >> >> My searches find 2 down in Cali with apparent wing failures, 1 down in >> Canadian TX. All of the three point to wing failures, add 2 to it and it >> brings us up to 5 Zodiac XL's with apparent wing failures. In an >> approximately 2 or so year span. How many Zodiac XL's are flying? FAA >> (which only shows registrations for US owned) shows about 225 or so. If >> we assume ( and this is a giant assumption) that the US market represents >> 60-70% of all Zodiac flying Zodiac XL's to about 3-400 FLYING Zodiac XL's. >> Can someone please substantiate or reject these approximations? I don't >> even consider the HD in these numbers because the wing is an entirely >> different spar design (we are talking about wing failures not rudder >> failures) If it were rudder failures I would consider their flying numbers >> in my figures since they both use the same rudder. >> >> What is the average number of hours on each Zodiac XL at this point in >> time? My guess would be about 150-200. (This is only my wild guess). >> >> So is it safe to say that there is 1 wing failure per 15000 hrs flown in a >> Zodiac XL? If you fly in a Zodiac for 500 hrs do you have an 3.3% chance >> of experiencing a wing failure? >> >> Guys I'm just trying to rattle around some numbers, I think my numbers are >> conservative. (More zodiacs than there actually are flying, more hours on >> each than there actually are etc.) >> >> I feel confident that if there is a design flaw Zenith will address the >> issue appropriately, hopefully the wreckage is in such condition that it >> can yield better information than the other wrecks that were inconclusive >> due to post crash fire. Hopefully the landing in the ocean in relatively >> shallow waters will allow for a more conclusive investigation. My >> thoughts and prayers go out to the families. >> >> If only one good thing comes of this accident, please let it be that IF >> there is a design issue, that it can be addressed. >> >> -------- >> One Rivet at a Time! >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=168995#168995 >> >> >> >> >> >> >> >> >> >> >> > > > >--------------------------------- >Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. > ________________________________ Message 59 ____________________________________ Time: 05:56:54 PM PST US From: Tracy Subject: Zenith-List: brs chute ? Thanks Les for the info ,you had emailed me your pics and i have beefed up the baggage panel but i would like to find out how big to make the cover,its for the round canister,and how deep the score has to be to make sure it will break through.if anybody has installed the type ,let me know Thanks ________________________________ Message 60 ____________________________________ Time: 06:06:52 PM PST US Subject: Zenith-List: Re: Accident From: "ashontz" A rib weighs about 8 ounces, I don't know if it even weighs that much, so ten extra ribs in the two wings is what, 5 pounds? [quote="ggower_99(at)yahoo.com"]Is like putting a Hummer and a Tracker side by side... :-) Here the C 152 and C 172 can hardly climb, heavyly overbuilt and expensive to fly... As women say around here (for everything they dont like) "I will rather die, than buy one of those" :-) Saludos Gary Gower I think we needed now a little of humor... Too many "experts" around here :-) Do not archive. ella wrote: > > Hi > Your numbers may be close. If there has been 5 wing failures in a certain > model aircraft I would say there has to be a reason why > I have just started my rudder and I am concerned. I can't remember > any wing failures in Cessna 172 or 150 but I could wrong > -- -------- Andy Shontz CH601XL - Corvair www.mykitlog.com/ashontz Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169126#169126 ________________________________ Message 61 ____________________________________ Time: 06:15:31 PM PST US From: Kevin Bonds Subject: Re: Zenith-List: Re: Accident I understand. It just illustrates a key point. The whole problem is, we never get enough info from those friggin reports. They only seem to give enough info to get the imagination going. I wish we had some sort of investigative team, from the homebuilt community, that could get access to investigate these accidents and provide more info than the NTSB is willing to--in the interest of safety. Kevin swater6 wrote: > > Kevin, > I meant to paraphrase the content of the NTSB report in my description of each accident. Sorry if it looks as though I was stating a conclusion, I only meant to describe each in a few words based on the ________________________________ Message 62 ____________________________________ Time: 06:27:19 PM PST US From: Jaybannist@cs.com Subject: Zenith-List: Accident This a question to all you folks who are so skeptical of the design and safety of the Zodiac CH 601XL: WHY IN THE WORLD ARE YOU BUILDING ONE??? Jay in Dallas 601XL N2630J "Lil Bruiser" Do not archive ________________________________ Message 63 ____________________________________ Time: 06:49:54 PM PST US From: "Paul Riedlinger" Subject: Re: Zenith-List: Accident Well said! There are sooooo many "arm chair engineers" who have all the solutions....extra ribs, no long range tanks, BRS, no wing lockers.... Planes crash all the time. It is a fact. If you look at the published stats, design failure accounts for very few of the causes of crashes. Usually it is the pilot error or weather related. I am tired of all of the pretend engineers. If you are an aerospace engineer, then you have the qualifications to post about the design. If not, you need to proceed your post with "I have no qualifications to make this recommendation but you guys should listen to me....." I have a great deal of faith in Chris Hintz and his abilities. I think before everyone posts, they need to ask themselves...what are my qualifications to question the design" Flame off. On Tue, Mar 11, 2008 at 9:22 PM, wrote: > > This a question to all you folks who are so skeptical of the design and > safety of the Zodiac CH 601XL: > > WHY IN THE WORLD ARE YOU BUILDING ONE??? > > Jay in Dallas 601XL N2630J "Lil Bruiser" > Do not archive > > -- Paul Riedlinger cndmovn@gmail.com ________________________________ Message 64 ____________________________________ Time: 07:06:25 PM PST US From: "Craig Payne" Subject: RE: Zenith-List: Accident > WHY IN THE WORLD ARE YOU BUILDING ONE??? I was going to name my XL "Plane Ugly". Now I'm leaning towards "Deathtrap" (very big smile). -- Craig Do not archive ________________________________ Message 65 ____________________________________ Time: 07:31:18 PM PST US From: Subject: Re: Zenith-List: Accident Paul, there really are sooooo many arm chair engineers with solutions. Your right and I agree I believe Chris Henitz is a great designer. Other designers have missed things and miscalculated so lets not forget we are all human and he could have made a error. Me I look at the fact of so many XL accidents versus very few HD and HDS accidents, maybe a flaw creeped in on the new design? ----- Original Message ----- From: Paul Riedlinger To: zenith-list@matronics.com Sent: Tuesday, March 11, 2008 6:46 PM Subject: Re: Zenith-List: Accident Well said! There are sooooo many "arm chair engineers" who have all the solutions....extra ribs, no long range tanks, BRS, no wing lockers.... Planes crash all the time. It is a fact. If you look at the published stats, design failure accounts for very few of the causes of crashes. Usually it is the pilot error or weather related. I am tired of all of the pretend engineers. If you are an aerospace engineer, then you have the qualifications to post about the design. If not, you need to proceed your post with "I have no qualifications to make this recommendation but you guys should listen to me....." I have a great deal of faith in Chris Hintz and his abilities. I think before everyone posts, they need to ask themselves...what are my qualifications to question the design" Flame off. On Tue, Mar 11, 2008 at 9:22 PM, wrote: This a question to all you folks who are so skeptical of the design and safety of the Zodiac CH 601XL: WHY IN THE WORLD ARE YOU BUILDING ONE??? Jay in Dallas 601XL N2630J "Lil Bruiser" Do not archive -- Paul Riedlinger cndmovn@gmail.com ________________________________ Message 66 ____________________________________ Time: 07:31:57 PM PST US Subject: Zenith-List: Re: brs chute ? From: "cookwithgas" I couldn't tell from your email if you are building a 601XL or not, but if you are, you can cut the hole after the fuselage is finished. If you talk to the BRS folks, they will answer all of your questions. When you buy the BRS, they send you a "frangible" plastic part that is the proper size for your parachute. I put some pictures here of my BRS installation: http://www.cooknwithgas.com/BRS.html Scott Laughlin 601XL/Corvair finished & flying www.cooknwithgas.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169152#169152 ________________________________ Message 67 ____________________________________ Time: 07:42:15 PM PST US Subject: Zenith-List: Re: XL - success stories From: "cookwithgas" Tim: Time on Hobbs: 48.7 hours Overall Satisfaction - Absolutely loving it. The Corvair engine is running great and I get lots of comments on how good it sounds. It is easy to fly I'm having a blast. The weather has been a real challenge, but I've been having so much fun I hardly notice the frozen toes and fingers. I'm really looking forward to some warmer weather. Scott Laughlin - N5SL - Omaha, Nebraska Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169158#169158 ________________________________ Message 68 ____________________________________ Time: 08:40:15 PM PST US From: "steve" Subject: Zenith-List: Fish Eye Update So your thinking about painting your own airplane. Good idea. I m old, stubborn and sometime a whiner. I ve had fish eyes appear from the very first time I pulled the spray gun trigger. Thanks to you guys and other builders, I ve learned the hard way about painting aluminum airplanes. I knew about making sure the air coming from the compressor was dry and clean. I knew but being stubborn, I knew more than YOU.... OK, I confess I m a stupit dumb poop. I purchased a filter ( inline) from Harbor Freight. It looks good but I still had fish eyes all over the painted surfaces... Yesterday I went to home Depot and bought a better quality oil.water separator (filter) AND a new air hose. Today I painted a wing. AMAZING! Its very nice (not perfect) but no fish eye..... After painting I cleaned up everything and went over to the new filter. Man O man, I could see extremely small oil droplets. I mean small. Not a pin head size but a pin point. Hardly visible but black as coal.. That's it....OIL... Black gold. If I had not been so stubborn and really listened, I would not have wasted $400 worth of paint and saved hours of sanding and repainting.... If you do the painting yourself it will be rewarding. Just don't do like me and try to reinvent proven work practices. Steve Owner: Steves Aircraft Painting Service. NOT! ________________________________ Message 69 ____________________________________ Time: 09:24:44 PM PST US From: Jay Maynard Subject: Re: Zenith-List: Accident On Tue, Mar 11, 2008 at 09:46:41PM -0400, Paul Riedlinger wrote: > I have a great deal of faith in Chris Hintz and his abilities. I think > before everyone posts, they need to ask themselves...what are my > qualifications to question the design" Not all of us are builders. My concern is simple: Am I about to spend $130K on an aircraft with a design flaw that makes the wings fall off? I'm nearly 100% certain that answer is no, but I'd feel better if that little bit of doubt were removed. -- Jay Maynard, K5ZC http://www.conmicro.com http://jmaynard.livejournal.com http://www.tronguy.net Fairmont, MN (FRM) (Yes, that's me!) AMD Zodiac CH601XLi N55ZC (getting ready to order) ________________________________ Message 70 ____________________________________ Time: 11:00:04 PM PST US Subject: Zenith-List: Re: Accident From: "mwtucker" It is easy to try and second-guess a design based on some supposed facts from media stories and eyewitnesses. Yes, its true that most of us are not aeronautical engineers But I think that it is constructive to discuss the accidents, keeping in mind that we may not know all the facts. That said, it does seem that we may want to make note of the fact that wing structural failure seems to be coming up as a common thread. Has wing structural failure been mentioned in relation to accidents of other aircraft (even certified designs)? We all know that flight into thunderstorms and/or loss of control can over-stress the airframe and result in failure. But I must admit that I am a bit concerned about the supposed in-flight structural failures on the 601XL. I know that Chris Heintz did a re-evaluation of the wing structure and loading after two supposed in-flight wing failure accident reports. But these were static load tests and would not expose any dynamic problems related to flutter or torsional deflections that may lead to wing failure. I have attended the rudder workshop at Zenith and am getting pretty close to making the commitment to go with a 601XL. I plan to ask them at Sun-n-Fun about the wing issue, although I would imagine that they will not tell me anything that I dont already know. Again, we dont want to jump to conclusions. I could wait and go with a Vans S-12 or a RANS 19 But those are new designs and could also have design problems. In fact, one of the reasons I was looking at the 601 XL is that the designer is well-known and respected and the design has been flying for awhile. Does anyone know if there are any similar structural failures on other AB aircraft? Again, we are assuming that there was, in fact a structural wing failure. I guess that we dont really know for sure. What type of flight testing has the 601XL design been through? Are there any flight test requirements that subject the airframe to the limits of the loading? I think the plane is rated to +/- 6 G? Does flight testing require that to be demonstrated? As to Jays comment why are we building the 601XLs in light of the alleged in-flight structural failures? I imagine that most people who are in the process of building a 601XL started their kits before they were aware of the several accidents in question. Some responses on the forum are suggesting that the aircraft will be fine as long as it is flown properly In a 172, I once ran into clear-air turbulence over the mountains of Pennsylvania and it scared me to death. There was nothing I could do to prevent that incident. Can the 601XL survive an upset like that? Let me close in saying that we dont really know for sure about the potential structural failures. Its possible that they could all be explained by airframe failure due to loss of control by the pilot (e.g. birdstrike, flight into storm, accidental rapid movement of the controls, etc.). Thanks, Mike Read this topic online here: http://forums.matronics.com/viewtopic.php?p=169180#169180 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/zenith-list Browse Digests http://www.matronics.com/digest/zenith-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.