Some are having an issue going past page 9 of this Q&A so I am starting a new discussion.

Please note that the upgrade package kit goes well beyond just meeting the FAA’s conservative
methods and no changes are being considered.

Like previous Q&A's, post all your questions / concerns at the bottom of the last page of this Q&A.  If I do not have the answer, I will consult with Chris Heintz and or other engineers.
If you have a very technical question or just want to vent, call me at 705-526-2871.
Thank you for your continued support.
Mathieu Heintz
Zenair Ltd

Views: 2884

Replies are closed for this discussion.

Replies to This Discussion

How about a workshop at Sun-In-Fun where builders can help perform the mods on a aircraft, followed by a complete load test for everyone to witness. Don't argue with the FAA about if the numbers are 5% high or low, just use the numbers they want. Include everything in the load test, wings, flaps, aerlons, fuselage, horizontal stabilizer and elevator. Include everything so their is nothing left to question. I've noticed some unfinished quick build kits on Barnstormers that are very cheap.

5% is not going to make a otherwise safe aircraft unsafe nor is it going to make a unsafe airplane safe.
Thats a great idea Mike!!! It appears to me that Zenith and Zenair have the most to loose in this matter. If they don't prove well beyond a doubt that the mods have brought the structure up the specs they advertise (600kg) then they have no chance of EVER selling another Zodiac. Imagine how Quick the news would spread from sun n fun that a load test was conducted and It passed! (hopefully).
Just a thought and mine to boot. All we really know is that there has been in-flight break ups. Other than that no one knows the root cause. Whether it is mechanical, weather, medical, mental or physical that started the breakup. What we do know is that Zenith has been working on the problem with various agencies to cure the unknown . They collectively have come up with the upgrade kit that they all agreed on. My 601X is neither AMD built or kit built. I bought a set of plans got a hammer and 1280 hours later and three days before the saib came out I had just riveted down last of the major sheet metal .I am still a long ways away from maiden flight but I get closer with each passing week. Mine is my own of Chris’s design I followed his plans religiously. I have also ordered my upgrade kit. I have no more or no less invested than anyone else as a life is a life. If there needs to be more testing and additional funds are needed I will also help out. What I will not do is fuel the fire.
Jon B.
Continuing on to maiden flight
See my thoughts above.
Ladies and Gents,
Reading everyone's comments about what should be done to put the XLs/650s on sound footing and how it should be done -- shows great concern.
I think that you all will agree with me that the Heintzs have performed to the utmost of their ability! It sounds like these tasks, litigation, etc., has strained their financial position.
Now the FAA is asking for more blood?
There is an old adage that states "You can't fight city hall" -- the FAA being city hall.
We need someone with lots of horsepower and expertise to advise and ramrod this project.
He/she won't be cheap!
Also, I agree that in order to placate the FAA another airframe will have to be destroyed in testing.
The successful outcome of this project will benefit us all because we'll have product that can be flown, sold without a heavy financial loss and liability, plus the Heintzs will remain in business to support us.
There are many 601/650 drivers that have offered, on this site as well as the matrix, monetary support and willingness to act as gophers in getting this problem resolved!
This is going to cost a lot of money!
I, for one, will throw my hat in the ring to volunteer as a gopher (if needed) and will support the cause financially.
Mack Kreizenbeck

I agree 100%. I will pitch in financially if needed also. Others have also posted this.

Mathieu, please get in touch with the legal department at EAA. They will bend over backwards to help you in this situation. I live a mile away from headquarters and I know most of the folks over there. If you want me to help let me know. They have engineers, lobbiests, anything you need. They know how to talk to the feds and they are relentless! As Mack said, horsepower and expertice!

Joe in Oshkosh
Mathieu and Zodiac builders/flyers
I can add very little beyond what so many have already so eloquently stated. I am moving forward with my 650 and am enjoying the challenge of my first homebuilt project. I have had nothing but exemplary relations with Roger and the gang at ZAC and I could not ask for any better help than what they have provided . They have even been willing to accept my suggestions on issues that have come along with the change to the 650 which any altered design might have.
I too am not interested in the politics and I could not comprehend all the intricasies anyway.
What i am intersted in is what all have said, complete testing to verify beyond a doubt our planes will be as robust and strong as we had been led to believe.
I too would be willing to contribute funds to help the Zodiac family, builders as well as the Heintz family move forward and do whatever testing someone can determine from a knowledgible position will put this to rest.
Everyone benefits by proving the upgraded plane. As builders we will be well served and Zenith can hopefully move past this very discouraging juncture in their lives as well. I can only hope for their continued success.
We need someone to step forward if they have the expertese and help us score that touchdown .
Respectfully, Jerry
If I can get a statement from the FAA stating that we do not need to do additional load testing, will that change anyone's opinion about doing more testing?

If an independent engineer confirms that the aircraft load tested by us exceeds FAR 23 requirements, will that change anyone's opinion about doing more testing?
You can please some builders all the time, and all the builders some of the time, but never all the builders all the time.

Do what YOU (and your dad, since his reputation has a stake in this) believe is best for Zenair and your customers. If additional funding is needed, let us know.
If the FAA changes its story and says no more testing is needed then I could live with that. However the best PR move would be to get the letter saying no more testing is needed then do it ANYWAY.

To all,
I just got of the phone with the FAA. They have agreed to send us a formal letter, outlining and clarifying what they want from us. We will than respond to their demands. I will post both letters for all to see.

In the meantime...
There has been a lot of discussions about the aircraft load test and there is no point talking about this anymore until we know the FAA's position on this.

However, I would think that the greater concern for all would be flutter. I think that a flutter test and or flight or GVT and or computer analysis etc. may be a good idea. Depending on which one, the costs could be quite huge.

Any thoughts on this?
I like the attitude that we will do what the FAA demands. However I think we should keep in mind that it might turn out to be prudent to push back on them somewhat depending on what they ask for. I suspect it is in the FAA’s interest to make sure that they don’t end up looking bad. To that end they might ask for a series of tests which are ridiculously expensive and out of line with what they have required other light-sport manufacturers to conduct. We should not offer to do whatever they want. We should agree to what is prudent which may require negotiation.

I don’t suggest that we should cheat the system or that we should have an attitude that “safety does not matter”. Safety matters; it’s just that a quest for safety can rarely be perused to the absolute extreme or without regard to cost. Even NASA can’t do that. So let’s see what they want, hope it is reasonable, negotiate if necessary then do what we can agree to.

I do think that learning more about the behavior of the Zodiac in dynamic conditions is more important than yet another simple load test. With all the extra strength I just put into my own airplane it’s hard to see why it would now fail a load test that it previously was more-or-less able to pass, if just barely. I think much less is known about the airplane’s behavior near to and just beyond its intended flight envelope. Call it flutter or wing oscillation or whatever – such things can load up the structure very quickly in ways a simple load test will never tell you about. These are the types of tests I would like to see, but not at ANY cost. Personally I would be willing to put up something like $1,000 - $2,000 towards such tests.



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