---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Sat 05/19/07: 20 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:08 AM - Re: 601HD Bungee (Dave Johnson) 2. 04:09 AM - Re: Final letter on thread (Paul Mulwitz) 3. 04:10 AM - 601HD Bungees () 4. 04:43 AM - Re: Re: Anybody delete the cabin access step?? (Gary Ray) 5. 06:45 AM - Re: Anybody delete the cabin access step?? (Ron Lendon) 6. 07:59 AM - Re: Re: Anybody delete the cabin access step?? (Robin Bellach) 7. 08:14 AM - Re: Re: Anybody delete the cabin access step?? (Michael Valentine) 8. 09:22 AM - Questions (Joe) 9. 12:11 PM - Aileron Flutter Problems. (n787xl@aol.com) 10. 01:01 PM - Re: Aileron Flutter Problems. (n787xl@aol.com) 11. 01:58 PM - Re: Re: 601XL Fuselage build before wings (Darrell Haas) 12. 02:18 PM - Spar Insert - fitting Center Spar (Michael Valentine) 13. 03:34 PM - Re: Spar Insert - fitting Center Spar (Roger Pritchard) 14. 04:34 PM - Re: Re: 601XL Fuselage build before wings (Flydog1966@aol.com) 15. 04:34 PM - Re: Spar Insert - fitting Center Spar (Jaybannist@cs.com) 16. 04:57 PM - Anybody delete the cabin access step?? () 17. 05:28 PM - Re: Spar Insert - fitting Center Spar (Roger Pritchard) 18. 07:06 PM - Re: Spar Insert - fitting Center Spar (Roger Pritchard) 19. 07:06 PM - Re: 601XL Fuselage build before wings (Matt Ronics) 20. 09:32 PM - Re: Tire Pressure (David X) ________________________________ Message 1 _____________________________________ Time: 03:08:51 AM PST US From: "Dave Johnson" Subject: Re: Zenith-List: 601HD Bungee Try travis@kobushweldingandmachining.com he makes a bungee installation tool for the 601, I used it on mine and it works a treat. Dave Johnson ----- Original Message ----- From: Jeyoung65@aol.com To: zenith-list@matronics.com Sent: Saturday, May 19, 2007 2:52 AM Subject: Zenith-List: 601HD Bungee John, drawing 6-L-0 list all bungee as P/N: 1080HD for the 601HD. I have not installed mine so cann't help there but other's web site does show U clamps being used. Jerry-GA Hi List It looks like it is time to change the right main gear bungees on my 601HD. DO NOT ARCHIVE" ------------------------------------------------------------------------- ----- See what's free at AOL.com. ________________________________ Message 2 _____________________________________ Time: 04:09:04 AM PST US From: Paul Mulwitz Subject: Re: Zenith-List: Final letter on thread Hi Eldon, Nobody knows what the future holds, but I would like to try to answer your question. As a seasoned engineer I feel qualified to make an educated guess at how this will all turn out. I think the most likely outcome will be that Chris will study the XL structure for a year or so. He will make an intense effort that could not be equaled by any other person on earth with 5 years of effort. In the end he will report he has found nothing. Besides my own engineering experience with similar problems, I am reminded of the structural failures of the Beechcraft Bonanza. It had very similar circumstances surrounding a significant number of failures. It took decades of frequent losses of planes with all aboard before someone actually found a fix that improved the tail structure. Actually, I think it was a matter of adding some reinforcement to the fuselage in the AD. This kind of problem is very hard to resolve. The design has already passed all the normal tests, and there are many planes flying with no problem. It is likely that there is no problem at all and the accidents are just results from anomalies in the structure, rigging, or flying of the unfortunate planes. Even if there is a small design weakness that relates to these accidents it may be impossible to find it. The good news is having Chris look at the problem is the best possible chance for finding any problem that may have crept into the design. Now that he is on board the rest of us should rest easy and go on with our lives. We have done as much as we can about this issue. Perhaps this whole series of incidents will make us all pay a little more attention to the way our planes are rigged and flown. For those who just can't live with the remote possibility that their plane may suffer a structural failure there are other hobbies to take up like knitting or basket weaving. Please remember this is all just my opinion. It is worth every penny you paid for it. Paul XL fuselage do not archive At 10:21 AM 5/18/2007, you wrote: >As a builder (601XL) just getting started, I have read the last >three week's postings with both fascination and concern. As with >most builders, having neither the means nor the requisite >skills/knowledge to independently verify the airplane's structural >integrety, I am dependent upon those who speak for the company and >its product. I have met Chris Heintz only once, last fall-- who >would have believed that a lecture on rivets could have been so >absorbing-- and was impressed by his obvious competence. And now I >understand that he will re-evaluate the airplane's structure yet again. > >Big question: can you give us a sense of the time-frame involved in >this? That is, should we anticipate conclusions from him in, say, >weeks, or is this a multi-month undertaking? An indication of timing >might be of utility in deciding what to undertake, and how rapidly. > >Thanks, > >Elden J. ________________________________ Message 3 _____________________________________ Time: 04:10:00 AM PST US From: Subject: Zenith-List: 601HD Bungees John, I don't know if you saw my thread messages about the bungees on my 601HD a couple of months ago. Without going through the whole thing again, I had originally installed 1080HD bungees on both mains and the nose gear because that is what came with my kit in 1996. I recently repaced them while doing a gusset modification of my main gear. Although the plates on top of the wing were still down tight but the bungees were in terrible condition. I decided to install the 1080's upon reinstalling the gear. The plates now sit slightly up from the top of the wing. I now taxi "on the bungees" rather than the hard ride of before. I may have to replace them a little sooner when they stretch, but I believe I've done the right thing using the 1080. Now for doing the job, I feel sorry for you. That is the reason I installed the nut plate strips ( that I made up at time of construction) to make this job easier. I had put this info in the Zeninth Newsletter back in 1996 and Chris Heintz said that he didn't think what I had done was necessary. But I've been an aircraft mechanic for 51 years and I know we all have to do maintenance from time to time. I'm afraid a modification to install what I've done would be very hard to do now without undoing the gear box area of the wing center section. Maybe someone else on the thread will tell you how they did it (access to the nuts of the gear attach bolts ). I've heard of using special bent wrenches, extension handles, grease in the wrench to hold the nut etc. You'll also have to remove the wheel fork from the bottom of the gear leg so that you can devise a tool to stretch the bungee to remove the top plate and let the tension off of the bungees upon removal and to also install the new ones. I don't know what else I can tell you this at this time. Good luck and be carefull. Jim Hoak 601HD - 912UL - 541 hours John, you'll just have to bite the bullet and go at it! ________________________________ Message 4 _____________________________________ Time: 04:43:08 AM PST US From: "Gary Ray" Subject: Re: Zenith-List: Re: Anybody delete the cabin access step?? Ron There are already 4 matching nose ribs on the 601XL. Also when you sit on the front of the wing most of the weight comes down very near the main spar and more evenly distributed by the size of your A** than would be by the sole of your boot. Some care as to where you place your outboard hand is advised to keep it within the four rib area . If you try it I think you will see that you don't need to be very agile to make it work. If you find that you don't like it add the step. It is one of the last proceedures of construction anyway. ----- Original Message ----- From: "Ron Lendon" Sent: Saturday, May 19, 2007 12:38 AM Subject: Zenith-List: Re: Anybody delete the cabin access step?? > > Heard that question, sitting on the wing leading edge, asked of Chris Heintz at SnF 2007. His reply was to increase the number of nose ribs to match the 4 in the rear in that area. > > -------- > Ron Lendon, Clinton Township, MI > Corvair Zodiac XL, ScrapBuilder ;-) > http://www.mykitlog.com/rlendon > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=113713#113713 > > > -- 3:50 PM > > ________________________________ Message 5 _____________________________________ Time: 06:45:08 AM PST US Subject: Zenith-List: Re: Anybody delete the cabin access step?? From: "Ron Lendon" Gary Ray, The 8/05 6-W-7, 6-W-8, and 6-K-0 of 5/05 prints I have shows 3 nose ribs and I see no update posted by zenith. The NR1 is inline with RR1 NR2 is between RR2 and RR3 and NR4 is inline with RR4. Chris said to move NR2 inline with RR2 and add a NR inline with RR3. -------- Ron Lendon, Clinton Township, MI Corvair Zodiac XL, ScrapBuilder ;-) http://www.mykitlog.com/rlendon Read this topic online here: http://forums.matronics.com/viewtopic.php?p=113743#113743 ________________________________ Message 6 _____________________________________ Time: 07:59:47 AM PST US From: "Robin Bellach" <601zv@ritternet.com> Subject: Re: Zenith-List: Re: Anybody delete the cabin access step?? My 04/06/04 drawings have 4 inline nose ribs showing on 6-W-7 and 6-W-8 pages dated 03/04, and 4 were included with the wing kit. I have left out the access steps. DO NOT ARCHIVE ----- Original Message ----- From: "Ron Lendon" Sent: Saturday, May 19, 2007 8:44 AM Subject: Zenith-List: Re: Anybody delete the cabin access step?? > > Gary Ray, > > The 8/05 6-W-7, 6-W-8, and 6-K-0 of 5/05 prints I have shows 3 nose ribs > and I see no update posted by zenith. The NR1 is inline with RR1 NR2 is > between RR2 and RR3 and NR4 is inline with RR4. Chris said to move NR2 > inline with RR2 and add a NR inline with RR3. > > -------- > Ron Lendon, Clinton Township, MI > Corvair Zodiac XL, ScrapBuilder ;-) > http://www.mykitlog.com/rlendon > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=113743#113743 > > > ________________________________ Message 7 _____________________________________ Time: 08:14:40 AM PST US From: "Michael Valentine" Subject: Re: Zenith-List: Re: Anybody delete the cabin access step?? Everyone is right - the plans changed sometime between '04 and '05. I have late '03 wings with 4 ribs that I got from another builder, but my plans purchased in '05 show the number now reduced to 3. Michael in NH On 5/19/07, Robin Bellach <601zv@ritternet.com> wrote: > > > My 04/06/04 drawings have 4 inline nose ribs showing on 6-W-7 and 6-W-8 > pages dated 03/04, and 4 were included with the wing kit. I have left out > the access steps. > > DO NOT ARCHIVE > > ----- Original Message ----- > From: "Ron Lendon" > To: > Sent: Saturday, May 19, 2007 8:44 AM > Subject: Zenith-List: Re: Anybody delete the cabin access step?? > > > > > > Gary Ray, > > > > The 8/05 6-W-7, 6-W-8, and 6-K-0 of 5/05 prints I have shows 3 nose ribs > > and I see no update posted by zenith. The NR1 is inline with RR1 NR2 is > > between RR2 and RR3 and NR4 is inline with RR4. Chris said to move NR2 > > inline with RR2 and add a NR inline with RR3. > > > > -------- > > Ron Lendon, Clinton Township, MI > > Corvair Zodiac XL, ScrapBuilder ;-) > > http://www.mykitlog.com/rlendon > > > > ________________________________ Message 8 _____________________________________ Time: 09:22:56 AM PST US From: "Joe" Subject: Zenith-List: Questions Hi Everyone, I have a few questions and a comment: I'm not sure how you guys do the FAA data base searches, but is there a way to look for something that is common to all 4 accident airplanes, such as type of engine, 2 or 3 blade prop, wing baggage compartment, etc? Conventional stick or mid stick? If all 4 had the same engine, is it possible that at a certain RPM it sets up a vibration of some sort? Is it possible to to overcontrol the airplane using a center stick? Is the wreckage still available for inspection and can we hire someone with credentials to go out and look at it? Many years ago, I built a Prostar PT-2 homebuilt. The wing was simmilar to my 601 XL with aluminum ribs and skin, roughly the same size and thickness. The novel thing about the PT was the fact that the skin was bonded first to the ribs with a 3M automotive type 2 face tape, then riveted with the same kind of rivets we use! the adhesive took a mild set at first, and with age was almost indestructable! I had to remove an inboard rib and it took me an entire afternoon with a razor blade and laquer thinner! So I called 3M to find out what kind of tape adhesives they have on the market now. They have over 100 types to choose from in any thickness and strength. They have some types that are used for aluminum construction, and all are on a roll of 2 face tape in any width you want! So why not use this 3M adhesive two face tape between the ribs and the wing skin? It wouldn't change any stiffness or flexability issues with the design, it would only hold the parts together better. Joe in Oshkosh 601 XL ________________________________ Message 9 _____________________________________ Time: 12:11:15 PM PST US Subject: Zenith-List: Aileron Flutter Problems. From: n787xl@aol.com Everyone, If you are concerned with the multitude of crashes of the 601xl you owe it to yourself to get on the EAA.org web site and if you are a member log in. Find the article on "Control Surface Flutter Problems" and read it. Please click on the FIGURE 1. The figure shows an aileron with underbalanced, Balanced (100%) and overbalanced conditions. Read the paragraph starting. "Two of the three---------Conversely, the static underbalance, or tail heavy condition first described, is the least desirable as it may result in unpredictable flight performance. The next paragraph is very informative, and ends up saying "Don't you believe it! Any airplane can experience flutter . . . even your light and slow VW-powered job under certain conditions. I believe the ailerons should be 100% balanced. James Schultz RV-6a builder, done. 601xl , wings and tail done working of fuselage. ________________________________________________________________________ ________________________________ Message 10 ____________________________________ Time: 01:01:11 PM PST US Subject: Re: Zenith-List: Aileron Flutter Problems. From: n787xl@aol.com Everyone, I forgot to mention that the 601XL ailerons are not balanced. Add to that aileron cables not being under enough tension, it could or maybe has been bad?? Regards James Schultz -----Original Message----- From: n787xl@aol.com To: zenith-list@matronics.com Sent: Sat, 19 May 2007 12:09 PM Subject: Zenith-List: Aileron Flutter Problems. Everyone, If you are concerned with the multitude of crashes of the 601xl you owe it to yourself to get on the EAA.org web site and if you are a member log in. Find the article on "Control Surface Flutter Problems" and read it. Please click on the FIGURE 1. The figure shows an aileron with underbalanced, Balanced (100%) and overbalanced conditions. Read the paragraph starting. "Two of the three---------Conversely, the static underbalance, or tail heavy condition first described, is the least desirable as it may result in unpredictable flight performance. The next paragraph is very informative, and ends up saying "Don't you believe it! Any airplane can experience flutter . . . even your light and slow VW-powered job under certain conditions. I believe the ailerons should be 100% balanced. James Schultz RV-6a builder, done. 601xl , wings and tail done working of fuselage. ________________________________________________________________________ ________________________________ Message 11 ____________________________________ Time: 01:58:10 PM PST US From: "Darrell Haas" Subject: Re: Zenith-List: Re: 601XL Fuselage build before wings Question? I have good eyesight. Can a person looking into the sky at an airplane 1/2 mile really see the wings flutter? Where was the sun? I live 1/2 mile from an airport and they fly over my house about 35 a day. I've tried to analyze the wings while they fly over and I wouldn't bet I could have seen the wings flutter. Darrell Haas Wanting to build a plane ----- Original Message ----- From: "ashontz" Sent: Thursday, May 17, 2007 1:13 PM Subject: Zenith-List: Re: 601XL Fuselage build before wings > > When I read that part I assumed prop failure (benefit of the doubt) that > shook the plane apart, yet the report doesn't mention that. The report > also states as probably cause "Failure of wing structure due to unknown > causes". > > > Gig Giacona wrote: >> If you are going to quote it quote it all. That witness was 1/2 mile away >> and also heard the engine being "revved up" repeatedly. >> >> >> > One witness, located about 1/2 mile north of the accident site, stated >> > that he was outside on his break when his attention was drawn toward >> > the direction of the accident airplane that was flying overhead towards >> > Oakdale airport. The airplane was about 800 to 1,000 feet above ground >> > level (agl). He stated that he heard a "very loud" engine and it >> > sounded as if it were being "revved up" repeatedly. As the airplane >> > flew to the southwest, he saw the wings visibly vibrate, and observed >> > what he thought were pieces of metal separate from the airplane. The >> > witness stated that the engine noise momentarily increased in pitch and >> > volume before the "left wing collapsed and folded rearward against the" >> > fuselage of the airplane. The nose pitched down and the airplane >> > entered a spin to the right. The right wing collapsed upward and folded >> > back against the fuselage. He stated that the airplane impacted the >> > ground in a 45-degree angle, and exploded on impact. The witness >> > further reported! > that the wings remained attached to the airplane, but folded back during > the accident sequence. He added that he did not see any components > separate from the airplane prior to impacting the ground. >> > >> > Additional witnesses from various locations surrounding the accident >> > site reported that the airplane flew a wide arc to enter the traffic >> > pattern. The engine sounded very loud, as if it were alternately being >> > "revved up to full rpm and then going to idle." The left wing of the >> > airplane collapsed upward, and it entered a nose down 60-degree spin to >> > the right. The airplane completed one full revolution before the right >> > wing collapsed upward and folded back. The airplane then struck the >> > ground. >> > > > -------- > Andy Shontz > CH601XL - Corvair > www.mykitlog.com/ashontz > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=113431#113431 > > > ________________________________ Message 12 ____________________________________ Time: 02:18:04 PM PST US From: "Michael Valentine" Subject: Zenith-List: Spar Insert - fitting Center Spar Folks, I got my wing kit from another builder - he ordered it in late 2003. The guide now shows the use of spar inserts that appear to be mini spar sections built up by the factory. The inserts go in the center spar section as you align things on the cabin floor. I cannot find them in my kit. Does anyone know if this was a piece included in the earlier kits? If not, is there an alternate technique to align things that I should use? Thanks for the thoughts, Michael in NH do not archive ________________________________ Message 13 ____________________________________ Time: 03:34:25 PM PST US From: Roger Pritchard Subject: Re: Zenith-List: Spar Insert - fitting Center Spar Michael, Borrow mine! Roger Michael Valentine wrote: Folks, I got my wing kit from another builder - he ordered it in late 2003. The guide now shows the use of spar inserts that appear to be mini spar sections built up by the factory. The inserts go in the center spar section as you align things on the cabin floor. I cannot find them in my kit. Does anyone know if this was a piece included in the earlier kits? If not, is there an alternate technique to align things that I should use? Thanks for the thoughts, Michael in NH do not archive --------------------------------- Ready for the edge of your seat? Check out tonight's top picks on Yahoo! TV. ________________________________ Message 14 ____________________________________ Time: 04:34:13 PM PST US From: Flydog1966@aol.com Subject: Re: Zenith-List: Re: 601XL Fuselage build before wings In a message dated 5/19/2007 4:59:27 P.M. Eastern Daylight Time, Darrellhaas@verizon.net writes: Can a person looking into the sky at an airplane 1/2 mile really see the wings flutter? Maybe if the flutter was REAL big,like, right before they disintergrate ? do not archive ************************************** See what's free at http://www.aol.com. ________________________________ Message 15 ____________________________________ Time: 04:34:27 PM PST US From: Jaybannist@cs.com Subject: RE: Zenith-List: Spar Insert - fitting Center Spar Michael, Are you talking about the spar jigs? If so, those are throw-away parts you have to make to get the main spar center section and the rear spar aligned so that the wings will fit. I had them installed several times during fuselage construction. I also installed them to facilitate the installation of the flap actuator rods. I still have them stored under the fuselage. Questions? Jay "Michael Valentine" wrote: >Folks, I got my wing kit from another builder - he ordered it in late 2003. >The guide now shows the use of spar inserts that appear to be mini spar >sections built up by the factory. The inserts go in the center spar section >as you align things on the cabin floor. I cannot find them in my kit. Does >anyone know if this was a piece included in the earlier kits? If not, is >there an alternate technique to align things that I should use? > >Thanks for the thoughts, > >Michael in NH > >do not archive > ________________________________ Message 16 ____________________________________ Time: 04:57:38 PM PST US From: Subject: Zenith-List: Anybody delete the cabin access step?? Regardless of the number of nose ribs your kit has or whether or not you care to add one more nose rib, most of us can get onto the wing from the trailing edge without a step installed. Unless you have bum kness, you can (from the left side for example) put your left knee ove the flap onto the wing walk area and with your left hand gripping the cockpit side rail, you can pull your carcass, including the sole of your right foot, onto the wing walk. The key is to remember to drop the flaps to full extended position when you park the plane. With all the other little concessions to heavier conveniences that I have made, I am seriously considering leaving the entry step off my 601XL. A bit less weight, a bit less drag, and no opportunity for a heavy passenger to load his or her weight farther aft of the main wheels...... it's worth thinking about. For the seriously stiff or inflexible, a paint can with a string attached to the lid would be an option on occassion. Dred ________________________________ Message 17 ____________________________________ Time: 05:28:19 PM PST US From: Roger Pritchard Subject: RE: Zenith-List: Spar Insert - fitting Center Spar Michael, YOU can borrow mine anytime you want to. Roger "Michael Valentine" wrote: Folks, I got my wing kit from another builder - he ordered it in late 2003. The guide now shows the use of spar inserts that appear to be mini spar sections built up by the factory. The inserts go in the center spar section as you align things on the cabin floor. I cannot find them in my kit. Does anyone know if this was a piece included in the earlier kits? If not, is there an alternate technique to align things that I should use? Thanks for the thoughts, Michael in NH do not archive Fussy? Opinionated? Impossible to please? Perfect. Join Yahoo!'s user panel and lay it on us.http://us.rd.yahoo.com/evt=48516/*http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7 hot CTA = Join Yahoo!'s user panel ________________________________ Message 18 ____________________________________ Time: 07:06:16 PM PST US From: Roger Pritchard Subject: RE: Zenith-List: Spar Insert - fitting Center Spar Roger Pritchard wrote: Michael, You can borrow my wing jigs anytime that you want to. Roger =========================================================== --------------------------------- 8:00? 8:25? 8:40? Find a flick in no time with theYahoo! Search movie showtime shortcut. ________________________________ Message 19 ____________________________________ Time: 07:06:20 PM PST US Subject: Zenith-List: Re: 601XL Fuselage build before wings From: "Matt Ronics" Tail flutter video: http://www.vibrationdata.com/Animation/Twin.avi Read this topic online here: http://forums.matronics.com/viewtopic.php?p=113798#113798 ________________________________ Message 20 ____________________________________ Time: 09:32:08 PM PST US Subject: Zenith-List: Re: Tire Pressure From: "David X" Duh! Read the recommended tire pressure on the side of the tire. The aircraft does have suspension, afterall. -------- Zodiac 601 XL - CZAW Built - Rotax 912S DO NOT ARCHIVE Read this topic online here: http://forums.matronics.com/viewtopic.php?p=113816#113816 ------------------------------------------------------------------------------------- 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.