---------------------------------------------------------- Zenith601-List Digest Archive --- Total Messages Posted Thu 10/30/08: 25 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:19 AM - [Probable Spam] Re: XL wing fold in flight (willemdelange) 2. 04:28 AM - Re: XL wing fold in flight (willemdelange) 3. 05:32 AM - [Probable Spam] Re: XL wing fold in flight (countzero) 4. 05:37 AM - Re: Re: XL wing fold in flight (mversteeg) 5. 06:23 AM - [Probable Spam] Re: XL wing fold in flight (Gig Giacona) 6. 06:48 AM - how to make the wings stronger? (john butterfield) 7. 07:03 AM - Re: how to make the wings stronger? (countzero) 8. 07:07 AM - 601 Airworthiness Directive (K Dilks) 9. 07:16 AM - Re: how to make the wings stronger? (jaybannist@cs.com) 10. 07:35 AM - [Probable Spam] Re: XL wing fold in flight (pavel569) 11. 07:37 AM - Re: Re: how to make the wings stronger? (ZodieRocket) 12. 07:44 AM - Re: how to make the wings stronger? (K Dilks) 13. 08:16 AM - Re: [Probable Spam] Re: XL wing fold in flight (Dirk Zahtilla) 14. 09:16 AM - Re: how to make the wings stronger? (Jim Belcher) 15. 09:17 AM - Re: how to make the wings stronger? (Martin Pohl) 16. 12:41 PM - The UK LAA view on the Dutch XL (K Dilks) 17. 12:58 PM - Zenair Europe's comments on the Dutch accident and grounding (Craig Payne) 18. 01:51 PM - European 601 XL modifications (Peter Chapman) 19. 01:55 PM - Re: The UK LAA view on the Dutch XL (David Downey) 20. 02:19 PM - Re: [Probable Spam] Re: XL wing fold in flight (Terry Phillips) 21. 05:44 PM - Re: The UK LAA view on the Dutch XL (Debo Cox) 22. 05:46 PM - Re: how to make the wings stronger? (Joemotis@aol.com) 23. 06:00 PM - Re: how to make the wings stronger? (Craig Payne) 24. 06:17 PM - Re: how to make the wings stronger? (Joemotis@aol.com) 25. 07:55 PM - Re: how to make the wings stronger? () ________________________________ Message 1 _____________________________________ Time: 04:19:54 AM PST US Subject: Zenith601-List: [Probable Spam] Re: XL wing fold in flight From: "willemdelange" You are right that the lower MTOW is only because of the UL regulations in Europe. The CZAW XL version has exactly the same wing and fuselage design and uses the same materials. Only the main landing gear has been changed to a lighter composite one and the wheels are lighter. This is because under the German UL rules the empty weight must be around 290 kg. Other small changes can be found in finishing details of the canopy, instrument panel, center console and firewall forward parts. I expect zenair will dive in to the problem because it also affects the 650 Willem, The Netherlands -------- Willem de Lange CH601XL owner Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211144#211144 ________________________________ Message 2 _____________________________________ Time: 04:28:26 AM PST US Subject: Zenith601-List: Re: XL wing fold in flight From: "willemdelange" keith, the european design is not really different from the US version, the wing construction and the fuselage is the same. Just the main landing gear is of composite and the wheels some lighter. This is because the empty weight must be around 290 kg to meet the European regulations. The lower MTOW is just a matter of regulation. Other European changes are in details in the canopy, instrument panel and firewall forward. The 650 has the same wing design as the XL so I expect here the same problems. Willem The Netherlands. -------- Willem de Lange CH601XL owner Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211145#211145 ________________________________ Message 3 _____________________________________ Time: 05:32:26 AM PST US Subject: Zenith601-List: [Probable Spam] Re: XL wing fold in flight From: "countzero" Willem, I don't think it can be "exactly" the same, the Euro version has a different wing rigging angle to the US XL. When this rigging angle was used for the new 650; zenithair modified the rear spar attachment to reinforce it. So I assume the CZAW XL has a beefed up rear spar attach just like the 650 or maybe it doesn't need it with the lower gross weight. Why was the rigging angle changed anyway? Rob > The CZAW XL version has exactly the same wing and fuselage design Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211156#211156 ________________________________ Message 4 _____________________________________ Time: 05:37:26 AM PST US From: mversteeg Subject: Re: Zenith601-List: Re: XL wing fold in flight Hello All, As a native Dutch speaker living in Texas I looked at the original text: > Uit een globaal onderzoek van de onderwerptekeningen van het > Amerikaanseontwerp is naar > voren gekomen dat de uitkomst van de sterkteberekeningen door de > ontwerper wellicht te > optimistisch was. and the word 'globaal' does not equate in a 'comprehensive', as in covering completely or based on a full grasp, (of the) investigation. It could actually be translated as 'cursory', as in quick initial examination of the plans, suggesting that a more complete investigation is going to follow. This just to make sure that the intend of the message is not lost in translation. Clearly this doesn't say anything about the conclusion which may or may not be valid. Regards, Maarten Versteeg plans build 601XL, about to finish the second wing > Time: 12:48:42 PM PST US From: Jim Belcher <"z > 601"@anemicaardvark.com> Subject: Re: Zenith601-List: Re: XL wing fold > in flight On Tuesday 28 October 2008 14:17, Craig Payne wrote: >> > >> > >> > Key point is this: >> > >> > "A comprehensive examination design drawings of the U.S. draft has shown >> > that the outcome of the strength calculations by the designer was probably >> > too optimistic." >> > >> > How do we reconcile this with the actual load testing (which was said to >> > have been conducted by an independent outside engineer)? >> > > Assuming there is a problem, the difference may lie in how the testing was > done. The load testing I saw posted on the Zenith site appears to have been > static, rather than dynamic, testing. > -- ============================================= Those who can, do. > Those who can't, sue. =============================================== Those who can do, Those who can't simulate ________________________________ Message 5 _____________________________________ Time: 06:23:34 AM PST US Subject: Zenith601-List: [Probable Spam] Re: XL wing fold in flight From: "Gig Giacona" In the video that was included in the most recent addition of the newsletter it is clearly stated that one of the reason for the 650 is to combine the attributes of the different versions of the 601XL specifically named are the AMD LSA, the US Kit and the European versions. This tells me that there are differences and wing angle might not be the only one. -------- 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=211164#211164 ________________________________ Message 6 _____________________________________ Time: 06:48:34 AM PST US From: john butterfield Subject: Zenith601-List: how to make the wings stronger? Hi List I actually tend to believe that most of the wing accidents were caused by pilot error/judgment. However, not being an engineer, am wondering how one would go about making the wings stronger. There must be a way we could modify the wing/attaching points or whatever to add a lot of strength to the wing assembly. I have no idea or experience on how this could be done, but i am sure there are plenty of people on this list that could figure out a way. It may be lighter and cheaper that getting a parachute system. Even a parachute won't help if a wing falls off at low altitude. I certainly would give up a few (lot) pounds to not to ever have to worry about wing departure. john XL, corvair Torrance, CA ________________________________ Message 7 _____________________________________ Time: 07:03:51 AM PST US Subject: Zenith601-List: Re: how to make the wings stronger? From: "countzero" Hello John, You could reduce the loading on the wings by lowering your gross weight. This is not the same as improving the structure pound for pound but is far simpler for you to do. Rob Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211168#211168 ________________________________ Message 8 _____________________________________ Time: 07:07:32 AM PST US Subject: Zenith601-List: 601 Airworthiness Directive From: "K Dilks" Please follow this like to see what Zenair Europe say . regards to all Kev http://www.nak.no/mikro/html/Teknisk/Teknisk%20melding/AD_ZE-2008-01.pdf -------- Austria ...guess where I work! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211169#211169 ________________________________ Message 9 _____________________________________ Time: 07:16:48 AM PST US Subject: Re: Zenith601-List: how to make the wings stronger? From: jaybannist@cs.com John, This is not intended as a "flaming" response.? I just want share my thoughts on structural modifications. An aircraft structure is one of the most interdependent structural systems there is.? You can't just "beef up" one part without knowing how that effects stresses on adjacent parts and parts adjacent to those.? A building designer wouldn't dream of adding a floor to a high-rise building without checking all the existing columns, beams and foundations to see if they could take the additional weight and moments. In order to do that, he would have to have access to, and understand all the structural calculations. The same applies to an airplane.? I would not trust ANY structural modification unless I knew, without a doubt, that all the structural design calculations had been checked and that they would allow such a modification. An airplane structure is just not a good thing to "tinker" with. Jay in Dallas Do not archive -----Original Message----- From: john butterfield Sent: Thu, 30 Oct 2008 8:48 am Subject: Zenith601-List: how to make the wings stronger? Hi List I actually tend to believe that most of the wing accidents were caused by pilot error/judgment. However, not being an engineer, am wondering how one would go about making the wings stronger. There must be a way we could modify the wing/attaching points or whatever to add a lot of strength to the wing assembly. I have no idea or experience on how this could be done, but i am sure there are plenty of people on this list that could figure out a way. It may be lighter and cheaper that getting a parachute system. Even a parachute won't help if a wing falls off at low altitude. I certainly would give up a few (lot) pounds to not to ever have to worry about wing departure. john XL, corvair Torrance, CA ________________________________________________________________________ Email message sent from CompuServe - visit us today at http://www.cs.com ________________________________ Message 10 ____________________________________ Time: 07:35:26 AM PST US Subject: Zenith601-List: [Probable Spam] Re: XL wing fold in flight From: "pavel569" I just wonder who can fly these (if there is no other modification) - max gross weight for UL in Europe=992lbs, empty weight (with Rotax 912S installed)=690lbs, 24gal=92l of fuel=144lbs. Then you'll get useful load of 158lbs. I could fly it only at the morning before the breakfast and after bathroom use. I don't know how much weight you can save on the gear but i doubt it will be more than 20-30lbs. -------- Pavel CA Zodiac XL N581PM (Reserved) Stratus Subaru EA-81 Tail, flaps, ailerons, wings done, fuselage is on the table .... Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211174#211174 ________________________________ Message 11 ____________________________________ Time: 07:37:33 AM PST US From: "ZodieRocket" Subject: RE: Zenith601-List: Re: how to make the wings stronger? When we look at the incidents, some are looked upon as pilot error, a thunderstorm comes to mind. But also keep in mind that mechanical errors can also creep in (missing bolts and cable tension are foremost in my thoughts). There are many flying 601XL's and quite a few have amazing hours accumulated. Zenair has time and time again tested the design for many countries standards as well as use a 3rd party to test the structure. One thing I have seen in looking at some planes is that the cables are not to spec in tension. These may have been set properly prior to first flight but not stretched, which would allow slacking. We also tend not to own a tension meter of which I would recommend having. We have read letters from Chris on Zenith's website and AMD's as well as a letter in the Zenair Newsletter about the importance of cable tension. Attached is a letter issued from Zenair Europe as an AD. In America we can only see an AD from the FAA so if we look on Zeniths website we see a Zenair Safety Alert at http://www.zenithair.com/zodiac/xl/data/ad-ze-2008-01.pdf Read this and take it to action. IF you have been flying your plane check it before next flight with a proper gauge. IF you're building remember to pre-stretch your cables and check often during initial flights and in a set interval during the life of the plane. Entertaining an idea of changing a design that bears up in mathematical and physical structural testing seems fool hardy and ill advised. Ensuring that your plane is to standards as set forth by designer and AC43-13b would be far more prudent and well in the reach of each builder. My Thoughts. Mark Townsend Alma, Ontario Zodiac CH650 C-GOXL, CH701 Rotax 912, STOL CH750 Just started www.ch601.org / www.ch701.com ________________________________ Message 12 ____________________________________ Time: 07:44:45 AM PST US Subject: Zenith601-List: Re: how to make the wings stronger? From: "K Dilks" The euro plane empty weight is quoted as 265 KG most empty zodiacs come in at 320 to 340kg So besides the undercarrige where else can they save that much weight. I have looked hard to day around the net but I am sure they are using ,16 skins. Maybe not on CZAW planes but on the ones from Dynaero in Portugal.. Not also the the data for loading . 6g is the ultimate so operational is 4g . I wonder if guys are pulling 6 thinking there safe. The lower figure of 4 is somtimes give and is on the plans.Check ZAC web site. All in all with so many versions and makers / suppliers this is quite a mess to work out. -------- Austria ...guess where I work! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211176#211176 ________________________________ Message 13 ____________________________________ Time: 08:16:12 AM PST US From: "Dirk Zahtilla" Subject: Re: Zenith601-List: [Probable Spam] Re: XL wing fold in flight I agree there are serious questions here. How could you remove the weight of a Cont.O-200 in order to carry 2 people at that weight. Dousn't seem possible... Dirk ----- Original Message ----- From: "pavel569" Sent: Thursday, October 30, 2008 7:35 AM Subject: Zenith601-List: [Probable Spam] Re: XL wing fold in flight > > I just wonder who can fly these (if there is no other modification) - max > gross weight for UL in Europe=992lbs, empty weight (with Rotax 912S > installed)=690lbs, 24gal=92l of fuel=144lbs. Then you'll get useful load > of 158lbs. I could fly it only at the morning before the breakfast and > after bathroom use. I don't know how much weight you can save on the gear > but i doubt it will be more than 20-30lbs. > > -------- > Pavel > CA > Zodiac XL N581PM (Reserved) > Stratus Subaru EA-81 > Tail, flaps, ailerons, wings done, fuselage is on the table .... > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=211174#211174 > > > ________________________________ Message 14 ____________________________________ Time: 09:16:27 AM PST US From: Jim Belcher Subject: Re: Zenith601-List: how to make the wings stronger? On Thursday 30 October 2008 08:48, john butterfield wrote: > I actually tend to believe that most of the wing accidents were caused by > pilot error/judgment. However, not being an engineer, am wondering how one > would go about making the wings stronger. There must be a way we could > modify the wing/attaching points or whatever to add a lot of strength to > the wing assembly. First, let me say I agree with the caution that one cannot change one part of a structure without considering the impact on the rest of the structure. We can't afford to make structural changes to the design, without a lot more information than is available. Having said that, it has appeared to me (since I first looked at the design) that the 6 AN5 bolts which connect the wing spar to the carry-through spar are pretty small and few in number to the task. There isn't that much overlap between the wing spar and the carry-through spar to transfer the wing loading to the rest of the structure. The commercial designs with which I'm most familiar had more and larger bolts, and in some cases, close-tolerance bolts. There is, as I recall, much more overlap between the spars to allow for reasonable spacing between the extra bolts. Is this the problem? Only the results of the various accident reports will tell. But it could sure cause wing separation, if it is. ============================================= Those who can, do. Those who can't, sue. ================================================ Jim B. Belcher BS, MS Physics, math, Computer Science A&P/IA Instrument Rated Pilot General Radio Telephone Certificate ================================================ ________________________________ Message 15 ____________________________________ Time: 09:17:48 AM PST US Subject: Zenith601-List: Re: how to make the wings stronger? From: "Martin Pohl" The average empty weight for CZAW CH601XLs seems to be around 310 - 320 kg. The new European version might be different. I checked my kit and I can assure that (on my CZAW 601XL) the wing sheet thickness is 0.025". Cheers Martin[/quote] -------- Martin Pohl Zodiac XL QBK 8645 Jona, Switzerland www.pohltec.ch/ZodiacXL Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211194#211194 ________________________________ Message 16 ____________________________________ Time: 12:41:25 PM PST US Subject: Zenith601-List: The UK LAA view on the Dutch XL From: "K Dilks" Hope these links settle some minds out there. Cant wait to start building ! http://www.lightaircraftassociation.co.uk/engineering/ch601%20web.pdf http://www.lightaircraftassociation.co.uk/engineering/vno%20mag%20article.pdf -------- Austria ...guess where I work! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211245#211245 ________________________________ Message 17 ____________________________________ Time: 12:58:50 PM PST US From: "Craig Payne" Subject: Zenith601-List: Zenair Europe's comments on the Dutch accident and grounding >From http://www.zenairulm.com/News/index_files/Page349.htm: "Developing Situation with the Zodiac XL in the Netherlands: On Saturday October 25, Zenair Sarl was informed by a Dutch Zodiac XL owner that the Dutch CAA had issued an emergency Airworthiness Directive the previous day, calling for the immediate grounding of all Zodiac XL in the Netherlands, effective immediately. This came as a complete surprise to Zenair Europe, Zenair Ltd and Zenith Aircraft Co. as none of us had been previously contacted by the Dutch authorities. We were further surprised that the basis for the NL-CAA action was a preliminary accident report that offers no new findings regarding the Zodiac XL design. Rather it makes allusion to various other accidents and suggests that the "calculated strength" of the design is "probably too optimistic". Zenair is eager to discuss the basis for these statements with the Dutch CAA and is keenly awaiting the return of CAA staff from their seasonal holiday. In the mean time, we note that no past accident investigations involving the CH 601 XL has ever found fault with the basic design; two accidents (2006 & 2008) are still being researched by the NTSB in the USA - completed design analysis in each case, however, has already found the design's engineering to be sound. We can also note that the Zodiac XL is not approved in Europe just on "calculate strength", but on "demonstrated strength" as well (extensive load-testing). To help appease possible concerns among neighboring countries, Zenair has taken the initiative of issuing an AD of its own. This AD (No. ZE-2008-01) addresses an important issue that may have contributed to the accident currently being investigated in Holland. We hope to share our thoughts on the issue with the Dutch CAA as soon as we may, and look forward to assisting with the on-going investigation in any way that we can. We believe that everyone concerned here has a common goal: to quickly find the solution(s) that will permit the Zenair CH 601 XL to once again be deemed "airworthy" by the CAA in the Netherlands. Please return to this page periodically for updates on this evolving situation." And here is a link to the cable tension AD: http://www.zenairulm.com/News/pdfdocs/ZE-2008-01.pdf -- Craig ________________________________ Message 18 ____________________________________ Time: 01:51:12 PM PST US From: Peter Chapman Subject: Zenith601-List: European 601 XL modifications At 12:17 30-10-08, you wrote: Somebody really needs to have a good talk with Zenith and figure out what the differences between the different versions of the XL are. To an outsider here, the arguments seem to be going in circles. Are skin thicknesses changed or not? Aircraft designations get used loosely. There is the 601 XL ULM, with the ULM designating the light version. (ULM being a common acronym for ultralights in Europe, Ultra-Lger-Motoris). But sometimes the ULM isn't specified for an XL. It's not clear to me whether there is a normal empty weight 601 XL in Europe, or if all have had the lightening program done. And it starts to look like the gross weight is not fundamentally changed for the lightened ones, that they are still apparently good for 4g at 1320 lbs, but the gross weight is reduced as needed if operated in a local ultralight category. But that's not clear. For the 650, there's the 650 E (E for Europe), sometimes listed with the same specs as the 601 XL in Europe. I haven't seen much in some simple web searches about lightening the XL for Europe: --From http://www.zenairulm.com/Home/: "As with previous European 601s, the 650 E will again come equipped with a two-piece landing gear system and various other light-weight components including wheels, brakes and smaller fuel tanks (2 x 46 liters)." (= 12 gallons, vs. 15 gallon tanks for the US version.) -- From airpal.eu: "Zenair has developed the Zodiac CH 650 E / CH 601 XL ULM version specifically for the European market, where light aircraft rules restrict the gross weight to 450 kg. (992 lbs.). The lightened European Zodiac XL is the result of continuing development, and is now available as a all-new "100% Finished Airframe" Quick-Build Aircraft Kit. The standard ZODIAC XL ULM kits, manufactured by Zenith Aircraft in the United States, are being distributed across Europe from Zenair Europe www.zenairulm.com/Home/index.htm (Belgium/France) and established Zenair dealers www.zenairulm.com/Representatives/index_files/Page1679.htm . Lighter materials are used in the European version of the XL. This includes an all-new lightweight composite landing gear main spring, lighter European-made wheels and brakes, and some lightened airframe items. As tested with the standard 100-hp Rotax 912S engine installation, a basic European Zodiac XL ULM weighs just 265 kg. (585 lbs.)" It is still a pretty aggressive weight reduction program, given that the standard XL is quoted as 690 lbs empty, also with a 912 S, 105 pounds more. Factory numbers are of course just a starting point and don't always reflect the typical aircraft. Martin Pohl in his 75 page engineering analysis uses 310 kg or 683 lbs as typical for flying European XL's. The weight category a pilot will use will naturally affect his choice of optional equipment. So it is still uncertain (to me) exactly what a European 601 XL is. Peter Chapman Toronto, ON 601 HDS / 912 / C-GZDC ________________________________ Message 19 ____________________________________ Time: 01:55:12 PM PST US From: David Downey Subject: Re: Zenith601-List: The UK LAA view on the Dutch XL I think you should post these files to the files area of the group. David L. Downey Harleysville-(SE) PA, USA --- On Thu, 10/30/08, K Dilks wrote: From: K Dilks Subject: Zenith601-List: The UK LAA view on the Dutch XL Hope these links settle some minds out there. Cant wait to start building ! http://www.lightaircraftassociation.co.uk/engineering/ch601%20web.pdf http://www.lightaircraftassociation.co.uk/engineering/vno%20mag%20article.p df -------- Austria ...guess where I work! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=211245#211245 =0A=0A=0A ________________________________ Message 20 ____________________________________ Time: 02:19:22 PM PST US From: "Terry Phillips" Subject: Re: Zenith601-List: [Probable Spam] Re: XL wing fold in flight Larry Could you please contact me offline? Thank you. Terry do not archive -----Original message----- From: LHusky@aol.com Subject: Re: Zenith601-List: [Probable Spam] Re: XL wing fold in flight > I have to agree with you Alberto. I thought the quality of the plane and > the construction was excellent. I have not seen a QBK in the US that was built > as good. > > Larry Husky > Madras, Oregon ________________________________ Message 21 ____________________________________ Time: 05:44:08 PM PST US From: Debo Cox Subject: Re: Zenith601-List: The UK LAA view on the Dutch XL Great articles Kevin. Thanks for posting them. The Vno one is a keeper. Debo Cox Scratchbuilt XL/Corvair Airframe 80% complete www.mykitlog.com/debo do not archive --- On Thu, 10/30/08, K Dilks wrote: > From: K Dilks > Subject: Zenith601-List: The UK LAA view on the Dutch XL > To: zenith601-list@matronics.com > Date: Thursday, October 30, 2008, 3:41 PM > > > Hope these links settle some minds out there. > > Cant wait to start building ! > > http://www.lightaircraftassociation.co.uk/engineering/ch601%20web.pdf > > > http://www.lightaircraftassociation.co.uk/engineering/vno%20mag%20article.pdf > > -------- > Austria ...guess where I work! > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=211245#211245 > > > > > > > > http://www.matronics.com/Navigator?Zenith601-List ________________________________ Message 22 ____________________________________ Time: 05:46:53 PM PST US From: Joemotis@aol.com Subject: Re: Zenith601-List: how to make the wings stronger? Maybe we should learn from this pilot! _http://www.youtube.com/watch?v=XRCbkBfdBrQ&eurl=http://www.chilloutzone.de/fi les/08102703.html_ (http://www.youtube.com/watch?v=XRCbkBfdBrQ&eurl=http://www.chilloutzone.de/files/08102703.html) This is incredible. Joe Motis Do not archive In a message dated 10/30/2008 9:17:07 A.M. Pacific Daylight Time, z601@anemicaardvark.com writes: --> Zenith601-List message posted by: Jim Belcher On Thursday 30 October 2008 08:48, john butterfield wrote: > I actually tend to believe that most of the wing accidents were caused by > pilot error/judgment. However, not being an engineer, am wondering how one > would go about making the wings stronger. There must be a way we could > modify the wing/attaching points or whatever to add a lot of strength to > the wing assembly. First, let me say I agree with the caution that one cannot change one part of a structure without considering the impact on the rest of the structure. We can't afford to make structural changes to the design, without a lot more information than is available. Having said that, it has appeared to me (since I first looked at the design) that the 6 AN5 bolts which connect the wing spar to the carry-through spar are pretty small and few in number to the task. There isn't that much overlap between the wing spar and the carry-through spar to transfer the wing loading to the rest of the structure. The commercial designs with which I'm most familiar had more and larger bolts, and in some cases, close-tolerance bolts. There is, as I recall, much more overlap between the spars to allow for reasonable spacing between the extra bolts. Is this the problem? Only the results of the various accident reports will tell. But it could sure cause wing separation, if it is. ============================================= Those who can, do. Those who can't, sue. ================================================ Jim B. Belcher BS, MS Physics, math, Computer Science A&P/IA Instrument Rated Pilot General Radio Telephone Certificate ================================================ **************Plan your next getaway with AOL Travel. Check out Today's Hot 5 Travel Deals! ________________________________ Message 23 ____________________________________ Time: 06:00:17 PM PST US From: "Craig Payne" Subject: RE: Zenith601-List: how to make the wings stronger? Yeah (as previously mentioned) it is a pretty good fake: http://www.avweb.com/blogs/insider/AVwebInsiderBlog_ViralVideo_KillaThrill_L ostWingLanding_199096-1.html -- Craig From: owner-zenith601-list-server@matronics.com [mailto:owner-zenith601-list-server@matronics.com] On Behalf Of Joemotis@aol.com Sent: Thursday, October 30, 2008 6:45 PM Subject: Re: Zenith601-List: how to make the wings stronger? Maybe we should learn from this pilot! http://www.youtube.com/watch?v=XRCbkBfdBrQ &eurl=http://www.chilloutzone.de/files/08102703.html This is incredible. Joe Motis Do not archive In a message dated 10/30/2008 9:17:07 A.M. Pacific Daylight Time, z601@anemicaardvark.com writes: On Thursday 30 October 2008 08:48, john butterfield wrote: > I actually tend to believe that most of the wing accidents were caused by > pilot error/judgment. However, not being an engineer, am wondering how one > would go about making the wings stronger. There must be a way we could > modify the wing/attaching points or whatever to add a lot of strength to > the wing assembly. First, let me say I agree with the caution that one cannot change one part of a structure without considering the impact on the rest of the structure. We can't afford to make structural changes to the design, without a lot more information than is available. Having said that, it has appeared to me (since I first looked at the design) that the 6 AN5 bolts which connect the wing spar to the carry-through spar are pretty small and few in number to the task. There isn't that much overlap between the wing spar and the carry-through spar to transfer the wing loading to the rest of the structure. The commercial designs with which I'm most familiar had more and larger bolts, and in some cases, close-tolerance bolts. There is, as I recall, much more overlap between the spars to allow for reasonable spacing between the extra bolts. Is this the problem? Only the results of the various accident reports will tell. But it could sure cause wing separation, if it is. ============================================= Those who can, do. Those who can't, sue. ======================= Jim B. Belcher BS, MS Physics, math, Computer Science A&P/IA Instrument Rated Pilot General Radio Telephone Certificate ===================e the es y --> - MATRONICS WEB FORUMS nbsp; - List Contribution Web Site ; ======================== _____ Plan your next getaway with AOL Travel. Check p://travel.aol.com/discount-travel?ncid=emlcntustrav00000001> out Today's Hot 5 Travel Deals! ________________________________ Message 24 ____________________________________ Time: 06:17:28 PM PST US From: Joemotis@aol.com Subject: Re: Zenith601-List: how to make the wings stronger? It certainly faked me out! Joe Motis Do Not Archive In a message dated 10/30/2008 6:01:02 P.M. Pacific Daylight Time, craig@craigandjean.com writes: Yeah (as previously mentioned) it is a pretty good fake: _http://www.avweb.com/blogs/insider/AVwebInsiderBlog_ViralVideo_KillaThrill_Lo stWingLanding_199096-1.html_ (http://www.avweb.com/blogs/insider/AVwebInsiderBlog_ViralVideo_KillaThrill_LostWingLanding_199096-1.html) -- Craig From: owner-zenith601-list-server@matronics.com [mailto:owner-zenith601-list-server@matronics.com] On Behalf Of Joemotis@aol.com Sent: Thursday, October 30, 2008 6:45 PM Subject: Re: Zenith601-List: how to make the wings stronger? Maybe we should learn from this pilot! _http://www.youtube.com/watch?v=XRCbkBfdBrQ&eurl=http://www.chilloutzone.de/fi les/08102703.html_ (http://www.youtube.com/watch?v=XRCbkBfdBrQ&eurl=http://www.chilloutzone.de/files/08102703.html) This is incredible. Joe Motis Do not archive In a message dated 10/30/2008 9:17:07 A.M. Pacific Daylight Time, z601@anemicaardvark.com writes: --> Zenith601-List message posted by: Jim Belcher On Thursday 30 October 2008 08:48, john butterfield wrote: > I actually tend to believe that most of the wing accidents were caused by > pilot error/judgment. However, not being an engineer, am wondering how one > would go about making the wings stronger. There must be a way we could > modify the wing/attaching points or whatever to add a lot of strength to > the wing assembly. First, let me say I agree with the caution that one cannot change one part of a structure without considering the impact on the rest of the structure. We can't afford to make structural changes to the design, without a lot more information than is available. Having said that, it has appeared to me (since I first looked at the design) that the 6 AN5 bolts which connect the wing spar to the carry-through spar are pretty small and few in number to the task. There isn't that much overlap between the wing spar and the carry-through spar to transfer the wing loading to the rest of the structure. The commercial designs with which I'm most familiar had more and larger bolts, and in some cases, close-tolerance bolts. There is, as I recall, much more overlap between the spars to allow for reasonable spacing between the extra bolts. Is this the problem? Only the results of the various accident reports will tell. But it could sure cause wing separation, if it is. ==================== Those who can, do. Those who can't, sue. ======================= Jim B. Belcher BS, MS Physics, math, Computer Science A&P/IA Instrument Rated Pilot General Radio Telephone Certificate ===================e the es y --> - MATRONICS WEB FORUMS nbsp; - List Contribution Web Site ; ____________________________________ Plan your next getaway with AOL Travel. Check out Today's Hot 5 Travel Deals! http://www.matronics.com/Navigator?Zenith601-List http://forums.matronics.com http://www.matronics.com/contribution (http://www.matronics.com/Navigator?Zenith601-List) (http://www.matronics.com/contribution) **************Plan your next getaway with AOL Travel. Check out Today's Hot 5 Travel Deals! ________________________________ Message 25 ____________________________________ Time: 07:55:36 PM PST US From: Subject: Re: Zenith601-List: how to make the wings stronger? I'm not an engineer, and don't even play one in commercials, but I don't recall anything surfacing in any of the failures that indicated sheared through-bolts. 6 AN5's per wing ought to hold several thousand ponds more then 1320 at 6G's. However, the Dutch report is the first one, I think, to have mentioned that the spar reinforcements were twisted and bent outside the wing/fusalage connection. If memory serves, at that point you have two (roughly) quarter inch by one and a quarter solid aluminum bars, a web of .040 or .060 sheet, and a flange of .040, for top and bottom. All of that is held by driven rivets (I forget the size) It would be really useful to see pictures of the failed area. Could the rivets have not been tight? If the rivets didn't do their job, then the individual units weren't supporting each other, and the reinforcement bars could have given, one by one. Just a theory........ Paul Rodriguez 601XL/Corvair ----- Original Message ----- From: Jim Belcher To: zenith601-list@matronics.com Sent: Thursday, October 30, 2008 11:03 AM Subject: Re: Zenith601-List: how to make the wings stronger? > On Thursday 30 October 2008 08:48, john butterfield wrote: > I actually tend to believe that most of the wing accidents were caused by > pilot error/judgment. However, not being an engineer, am wondering how one > would go about making the wings stronger. There must be a way we could > modify the wing/attaching points or whatever to add a lot of strength to > the wing assembly. First, let me say I agree with the caution that one cannot change one part of a structure without considering the impact on the rest of the structure. We can't afford to make structural changes to the design, without a lot more information than is available. Having said that, it has appeared to me (since I first looked at the design) that the 6 AN5 bolts which connect the wing spar to the carry-through spar are pretty small and few in number to the task. There isn't that much overlap between the wing spar and the carry-through spar to transfer the wing loading to the rest of the structure. The commercial designs with which I'm most familiar had more and larger bolts, and in some cases, close-tolerance bolts. There is, as I recall, much more overlap between the spars to allow for reasonable spacing between the extra bolts. Is this the problem? Only the results of the various accident reports will tell. But it could sure cause wing separation, if it is. ==================== Those who can, do. Those who can't, sue. ======================= Jim B. Belcher BS, MS Physics, math, Computer Science A&P/IA Instrument Rated Pilot General Radio Telephone Certificate ======================= http://www.matronics.com/Navigator?Zenith601-List http://www.matronics.com/contribution ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith601-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith601-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/zenith601-list Browse Digests http://www.matronics.com/digest/zenith601-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.