Matronics Email Lists :: View topic - Report from OSH on 601xl update issues.

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

Report from OSH on 601xl update issues.
Goto page 1, 2, 3 Next

Matronics Email Lists Forum Index -> Zenith601-List

View previous topic :: View next topic

Author Message

psm(at)att.net
Guest

Posted: Tue Jul 27, 2010 2:40 pm Post subject: Report from OSH on 601xl update issues.

I attended the zenair forum presentation yesterday with Matthieu Heintz on the microphone and had a great conversation today with one of the high level FAA guys who has been involved with this issue for a long time (I also spoke with this same guy last year at Sun n Fun, and he actually remembered me as soon as he saw me . . . ).  

   

Nothng much has changed with Matthieu - it is all about tap dancing with him.  I left the presentation early and didn't bother getting into it with him again.  I feel we are lucky to have the update package for the XL and really can't expect much more from that direction.  

   

The FAA guy did a lot to make me feel more confident in the engineering behind the update package.  He told me the FAA engineers (the same guys who review designs for part 23 airplane engineering) went over the XL very carefully.  They spent thousands of man-hours on this effort.  It included the design before the update and a review of the design after inclusion of the update package that was engineered by Zenair.  At least this guy thinks the updated design is sound.  

   

I expressed concern that we never really learned the cause for the structure failures.  He told me I was wrong about that and that the problem was well documented In the 80 page report they made public last year.   His comment was that the wing was designed for only 1200 pounds (for the European ultralight market) gross weight but the operating weight was 1320.   For him (and maybe for me now) this explained not only the design issue behind the failures  but is also consistent with the location of the actual failures on the wing spars.  He was unsure if the wing failure caused flutter or the flutter caused the wing failures,  but he feels the update properly addresses this issue since it strengthens the wings and balances the ailerons.  

   

I am currently in the middle of installing the update package on my xl and plan to enter phase I testing in a month or two.  After this conversation I am now  more confident that I will actually put the plane into normal service at completion of phase I testing.  

   

Paul  

Posted from OSH  

   

   

       [quote][b]

chris Sinfield

Joined: 28 Nov 2006
Posts: 270
Location: Sydney Australia

Posted: Tue Jul 27, 2010 8:02 pm Post subject: Re: Report from OSH on 601xl update issues.

thanks for the post..



for us that have not been to Oshkosh



any other interesting zenith updates 



Oshkosh new things or deals you found?

Chris..

slook(at)mchsi.com
Guest

Posted: Wed Jul 28, 2010 6:21 am Post subject: Report from OSH on 601xl update issues.

Really? A design difference for 120 pounds causes the failures?



Steve



At 05:39 PM 7/27/2010, you wrote:



 	  Quote: 	
		  ...  His comment was that the wing was designed for only 1200 pounds 

(for the European ultralight market) gross weight but the operating 

weight was 1320.   For him (and maybe for me now) this explained not 

only the design issue behind the failures  but is also consistent 

with the location of the actual failures on the wing spars.  He was 

unsure if the wing failure caused flutter or the flutter caused the 

wing failures,  but he feels the update properly addresses this 

issue since it strengthens the wings and balances the ailerons.


	


Steve Look

Monticello, IL

www.ilrt66.com

"Dogs have owners, Cats have staff"

Z601c(at)anemicaardvark.c
Guest

Posted: Wed Jul 28, 2010 6:42 am Post subject: Report from OSH on 601xl update issues.

That was my reaction, Steve. Evidently, there must have been very little 

reserve for error. 



On Wednesday 28 July 2010 09:18:58 you wrote:

 	  Quote: 	
		   

 

 Really? A design difference for 120 pounds causes the failures?

 

 Steve

 

 At 05:39 PM 7/27/2010, you wrote:

 >...  His comment was that the wing was designed for only 1200 pounds

 >(for the European ultralight market) gross weight but the operating

 >weight was 1320.   For him (and maybe for me now) this explained not

 >only the design issue behind the failures  but is also consistent

 >with the location of the actual failures on the wing spars.  He was

 >unsure if the wing failure caused flutter or the flutter caused the

 >wing failures,  but he feels the update properly addresses this

 >issue since it strengthens the wings and balances the ailerons.

 

 Steve Look

 Monticello, IL

 www.ilrt66.com

 "Dogs have owners, Cats have staff"

 

 


	


-- 

========================================

                                       Jim B. Belcher

                                       BS,MS Physics

                                            A&P/IA

                      General Radio Telephone Certificate

                               Instrument Rated Pilot

                     Retired Aerospace Technical Manager

                         Semi-proficient Househusband

========================================

craig(at)craigandjean.com
Guest

Posted: Wed Jul 28, 2010 8:51 am Post subject: Report from OSH on 601xl update issues.

No, it was flutter! Somebody proved it, somewhere, on the Internet. That is

why the FAA approved fix has balance arms for the ailerons. 



-- Craig 



--

craig(at)craigandjean.com
Guest

Posted: Wed Jul 28, 2010 9:34 am Post subject: Report from OSH on 601xl update issues.

I'm trying to recall how many of the unexplained crashes involved solo

flights. Florida, Utah, others? Was the Yuba City, CA crash the only one

with two people aboard?



-- Craig 



--

craig(at)craigandjean.com
Guest

Posted: Wed Jul 28, 2010 9:43 am Post subject: Report from OSH on 601xl update issues.

To answer my own question: no, the Oakdale, CA crash (LAX06LA105) also had

two aboard.



-- Craig



--

LHusky

Joined: 19 Jun 2008
Posts: 86
Location: Madras, Oregon

Posted: Wed Jul 28, 2010 2:43 pm Post subject: Report from OSH on 601xl update issues.

The Arkansas accident was a solo flight if I remember right.  Also, I  think the Florida accident was a solo one.  

  

  In a message dated 7/28/2010 9:52:30 A.M. Pacific Daylight Time,  craig(at)craigandjean.com writes:

  	  Quote: 	
		  -->    Zenith601-List message posted by: "Craig Payne"    <craig(at)craigandjean.com>



No, it was flutter! Somebody proved it,    somewhere, on the Internet. That is

why the FAA approved fix has balance    arms for the ailerons. 



-- Craig 



-----Original    Message-----

From:    owner-zenith601-list-server(at)matronics.com

[mailto:owner-zenith601-list-server(at)matronics.com]    On Behalf Of Stephen R.

Look

Sent: Wednesday, July 28, 2010 7:19    AM

To: zenith601-list(at)matronics.com

Subject: Re: Zenith601-List: Report    from OSH on 601xl update issues.



--> Zenith601-List message posted    by: "Stephen R. Look" 

--> <slook(at)mchsi.com>



Really? A    design difference for 120 pounds causes the failures?



Steve



At    05:39 PM 7/27/2010, you wrote:



 	  Quote: 	
		  ...  His comment was that the    wing was designed for only 1200 pounds 

(for the European ultralight    market) gross weight but the operating

weight was 1320.   For    him (and maybe for me now) this explained not 

only the design issue    behind the failures  but is also consistent with 

the location of    the actual failures on the wing spars.  He was unsure 

if the wing    failure caused flutter or the flutter caused the wing 

failures,     but he feels the update properly addresses this issue since 

it    strengthens the wings and balances the ailerons.


	


Steve    Look

Monticello, IL

www.ilrt66.com

"Dogs have owners, Cats have    staff"  =========================    Use the  ties  Day  ================================================               - MATRONICS WEB FORUMS  ================================================             - List Contribution Web Site  sp;                             ===================================================



	


  [quote][b]

psm(at)att.net
Guest

Posted: Thu Jul 29, 2010 6:51 am Post subject: Report from OSH on 601xl update issues.

I don't want to argue over the issue of the final value of the upgrade

design.  I feel good about it, but I think each owner and flyer needs to

make up his own mind about design related risks with the XL.



That said, I do want to make one comment about the nature of the whole mess

and how the marginal design concept fits the known facts.  Perhaps the most

difficult part of this whole mess for me to understand has been the number

of accidents exerienced.  It has always been small compared to the number of

planes flying but too big to ignore.  This is exactly the result I would

expect from a design that was good but not quite good enough.  If there were

a realy large problem with the design the the number of accidents would be

much greater. 



The part of this I really like most is the new idea I got that there was

extensive review of the design details from FAA engineers who are quite

competent to do this review.  The fact they did a similar review of the

completed design after the upgrade is also comforting.



One detail I forget to mention in my report is that the FAA guys felt the XL

design failed to meet ASTM requirements before the upgrade and does meet

them after the upgrade.



Paul

from OSH



--

bryanmmartin

Joined: 10 Jan 2006
Posts: 1018

Posted: Thu Jul 29, 2010 7:33 am Post subject: Report from OSH on 601xl update issues.

The 601XL was designed before the LSA rule was even started and it was designed for the american market as an improvement over the 601HD. The original design gross weight was 1400 lbs, it was reduced to 1320 lbs to appeal to the LSA market. I don't know where this guy got the notion about a 1200 lb gross weight but it just goes to show that even the "experts" don't necessarily know what they are talking about when they get outside their area of expertise.

 	  Quote: 	

 At 05:39 PM 7/27/2010, you wrote:

 >...  His comment was that the wing was designed for only 1200 pounds

 >(for the European ultralight market) gross weight but the operating

 >weight was 1320.   For him (and maybe for me now) this explained not

 >only the design issue behind the failures  but is also consistent

 >with the location of the actual failures on the wing spars.  He was

 >unsure if the wing failure caused flutter or the flutter caused the

 >wing failures,  but he feels the update properly addresses this

 >issue since it strengthens the wings and balances the ailerons.

--

Bryan Martin

do not archive [quote][b]

_________________
--
Bryan Martin
N61BM, CH 601 XL, Stratus Subaru.
do not archive.

sabrina

Joined: 15 Jun 2009
Posts: 170

Posted: Thu Jul 29, 2010 9:54 am Post subject: Re: Report from OSH on 601xl update issues.

Do Not Archive

Last edited by sabrina on Thu Aug 05, 2010 2:25 pm; edited 1 time in total

slook(at)mchsi.com
Guest

Posted: Thu Jul 29, 2010 10:25 am Post subject: Report from OSH on 601xl update issues.

There is a big difference between saying "some guy" from the FAA says 

something and saying that the FAA says something.

When I can get a reference to a specific finding in writing issued by 

the FAA, I'll be less skeptical.



All of the supposition posted here without any basis in established 

fact does nothing but hurt Zenith and us, the owners/builders.



Steve



At 12:54 PM 7/29/2010, you wrote:

 	  Quote: 	
		  



CH sold us kits and plans for a +/- 6 G (ultimate) 1320 lb gross 

weight 160 MPH VNE vehicle.

The FAA would not be putting the number 1200 out there without 

either an admission from CH or solid engineering.

The fact that we have an airframe that was sold to us as a 'better 

than utility' category 1320 pound 160 MPH aircraft that is, in 

reality, a 1200 pound normal category 138 MPH aircraft is something 

we have to live with or modify.

We should be thankful to the FAA that we are still around to live with it.

Although 120 pounds does not sound like much.  When people fly into 

storms, near mountains, or over cliffs with their wings light (fuel 

low) OR load the craft beyond aft CG, bad things will happen.   It 

is not the number of people as much as it the gross weight and where 

the weight is located within the airframe.  The crashes seem to 

prove that an aft CG loaded 1250 pound XL punishes its main spar 

just as bad as a center CG loaded 1440 pound XL.

I am heading up to Air Venture in the morning for lunch with my 

favorite FAA type.   I am so proud they have finally come up with or 

extracted from CH, a set of de-rating numbers.


	


Steve Look

Monticello, IL

www.ilrt66.com

"Dogs have owners, Cats have staff"

sabrina

Joined: 15 Jun 2009
Posts: 170

Posted: Thu Jul 29, 2010 12:37 pm Post subject: Re: Report from OSH on 601xl update issues.

Do Not Archive

Last edited by sabrina on Thu Aug 05, 2010 2:25 pm; edited 1 time in total

slook(at)mchsi.com
Guest

Posted: Thu Jul 29, 2010 2:32 pm Post subject: Report from OSH on 601xl update issues.

What you and some others are asking us all to believe, is that CH is 

a criminal and a maniac as he would allow family and others fly in 

these aircraft knowing they are unsafe.

I have seen all the testing results which, near as I can tell, have 

proved nothing to indicate the design unsafe.

I have seen "fixes" mandated that have no proof of being required.

I have seen the value of my airplane diminished.

What I haven't seen is the slightest shred of credible evidence to 

back these claims against Zenith.



I believe the airplane is safe. Beyond that, I am not an aero 

engineer so I can not intelligently answer your questions. I could 

make up something but then I might sound like an FAA lawyer or an 

AOPA columnist.



Steve



At 03:37 PM 7/29/2010, you wrote:

 	  Quote: 	
		  



Steve, do you believe the kit, factory XL or plans without the 

modification can support more than 1200 pounds? Faster than 

138?  Utility category?


	


Steve Look

Monticello, IL

www.ilrt66.com

"Dogs have owners, Cats have staff"

sabrina

Joined: 15 Jun 2009
Posts: 170

Posted: Thu Jul 29, 2010 2:39 pm Post subject: Re: Report from OSH on 601xl update issues.

Do Not Archive

Last edited by sabrina on Thu Aug 05, 2010 2:26 pm; edited 1 time in total

sperry50(at)comcast.net
Guest

Posted: Thu Jul 29, 2010 3:19 pm Post subject: Report from OSH on 601xl update issues.

I too find it hard to believe that Chris would intentionally make false

claims about his airplane designs, even though I have never personally met

him. I have met Roger and the guys at the Mexico site and they all seem to

be "authentic" and no signs of being shysters. Hell, Roger crawled his ass

in the factory demonstrator for hour after hour. Do you really think he

would have done that if he felt there were problems not being disclosed?



If you buy a Mercedes and don't do the maintenance, you will eventually be

left on the side of the road. The only problem is it is a lot more dramatic

when an airplane does it. I feel comfortable with the "upgrades" and as far

as I plan to stress the airplane I feel it will do what I want. If I had

wanted a higher performance plane I would have opted for an RV and the extra

work and expense and sure as hell wish some of you guys would do the same

thing. I really get tired of reading all the attacks when all you had to do

was sell your stuff (yes, at a loss due to your bellyaching) and move on to

another design. I might buy the farm but again I can't believe Roger and the

other Mexico guys would have flown all those demonstrator hours with a plane

that was "defective"



That's just my opinion after reading hundreds of emails and my opinion is

just like my mom used to say - "opinions are like assholes, everyone has one

and most of them stink". Flame away if you like but I really don't give a

fat rats ass:-) Happy flying to you all, no matter what you are flying. 



Skip



--

sabrina

Joined: 15 Jun 2009
Posts: 170

Posted: Thu Jul 29, 2010 3:30 pm Post subject: Re: Report from OSH on 601xl update issues.

Do Not Archive

Last edited by sabrina on Thu Aug 05, 2010 2:26 pm; edited 1 time in total

jfowler120(at)verizon.net
Guest

Posted: Thu Jul 29, 2010 4:13 pm Post subject: Report from OSH on 601xl update issues.

Sabrina,



Skip has a great point -- about you.



Karl



--------------------------------------------------

From: "Sabrina" <chicago2paris(at)msn.com>

Sent: Thursday, July 29, 2010 7:30 PM

To: <zenith601-list(at)matronics.com>

Subject: Re: Report from OSH on 601xl update issues.



 	  Quote: 	
		   



 Roger did not fly the factory demo once the FAA issued their finding.  I 

 bet CH and Roger were just as surprised with the FAA findings as we were.



 That said, Roger getting into an airplane with me, that we both believed 

 was safe at 1320, is no great feat.   Hundreds of people reading this list 

 did the same thing.



 Engineers make mistakes, great engineers own up to their mistakes.





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=306736#306736

sabrina

Joined: 15 Jun 2009
Posts: 170

Posted: Thu Jul 29, 2010 4:50 pm Post subject: Re: Report from OSH on 601xl update issues.

Do Not Archive

Last edited by sabrina on Thu Aug 05, 2010 2:27 pm; edited 2 times in total

jfowler120(at)verizon.net
Guest

Posted: Thu Jul 29, 2010 5:02 pm Post subject: Report from OSH on 601xl update issues.

Sabrina,



What "Agent Orange fiasco in Laos" was that?



Karl

Raven45



--------------------------------------------------

From: "Sabrina" <chicago2paris(at)msn.com>

Sent: Thursday, July 29, 2010 8:50 PM

To: <zenith601-list(at)matronics.com>

Subject: Re: Report from OSH on 601xl update issues.



 	  Quote: 	
		   



 "Sabrina,  Skip has a great point...  Karl"



 Dear Mr. Polifka,



 Sorry to offend you.   Thank you for serving our country so well.   Did 

 you ever get to the bottom of the Agent Orange fiasco in Laos?



 Sabrina





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=306744#306744

Display posts from previous:

	Matronics Email Lists Forum Index -> Zenith601-List	All times are GMT - 8 Hours Goto page 1, 2, 3 Next
Page 1 of 3

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum