ELA 07 - Accident report - welding

[Steve_UK]

Back in summer 2015 French ELA 07 registration 34-ACG suffered a fatal accident.

The official BEA report is now available -worth a read ( use Google Translate ) - appears to show two in flight welding failures

The report has photos of these cracks and also photos of a similar crack from another ELA.


.
Part of the report translates as
"Several witnesses indicate that the gyroplane then quickly returns to the runway threshold 32 with the empennage ( Steve - ie fuselage/frame ) that seems partly disassociated. They add that they hear him pass with an unusual noise. Moments later, the autogyro hits the ground violently" The report can be found here https://www.bea.aero/uploads/tx_elydbrapports/BEA2015-0318.pdf

 

[FRANK'S]

OMG This is not good for them, if you have Stock In ELA it's too late.
I hope this will be fixed and no more lost of life.

I did not need translation.

 

[Vance]

I suspect they have improved their process and quality assurance since this accident since I have not heard of any other failures and only one crack. It appears to me there are lots of ELAs flying around.

This is an area of the frame I would focus on in a pre-flight and from the pictures I would guess the failure did not begin on the accident flight. I would have to feel the fracture to feel confident in that.

It is easy to anticipate the location of the failure in the ELA tail boom from the design.

Contained in the short book of things not to do with a welded joint on a square tube is welding across the tube. If you must weld across a tube use a properly designed gusset to manage the stress riser that is created by welding across the tube.

The Predator has areas of the frame and mast that I particularly focus on during preflight for this reason.

 

[Vance]

It appears they are feeding the rotor shake from the mast into bending the tail boom and the empennage is trying to dampen it.

In my opinion laying a single piece of sheet metal over top of the joint is not a proper fix and welding the ends across the tube adds another stress riser.

It is sad that someone had to die to learn this lesson once again.

Just yesterday I was discussing tail boom failure in a high thrust line gyroplane with a client and our conclusion was as long as the power was reduced and the empennage didn't reach the rotor it would be survivable if there wasn't a fire.

From the description of the accident the pilot may have left the power in and had a power push over.

 

[Mike G]

Steve
You're wasting your time, we discussed it here:

https://www.rotaryforum.com/forum/rotorcraft/general-discussion/1122372-resonance/page3

and nobody was interested.
​​​​​​​The conclusion seems to be that since the only members who talked about it were one owner, of debatable technical competence, and a competitor to ELA there was nothing to discuss and that it doesn't matter if the frame cracks because of lousy welding, you will pick it up in a thorough pre flight.

It was also said that ELA's terrible stainless steel welding quality isn't a problem for the US because they are buying Eclipses that have 4130 frames. Nobody seems to have picked up on the fact that if they don't know how to weld stainless there's a pretty good chance they don't know how to weld 4130 either.

I'd start a list about the problems with the Eclipse but I learned my lesson with the "Resonance" thread.

Mike G

 

[Vance]

Steve
You're wasting your time, we discussed it here:

https://www.rotaryforum.com/forum/ro...esonance/page3

and nobody was interested.
The conclusion seems to be that since the only members who talked about it were one owner, of debatable technical competence, and a competitor to ELA there was nothing to discuss and that it doesn't matter if the frame cracks because of lousy welding, you will pick it up in a thorough pre flight.

It was also said that ELA's terrible stainless steel welding quality isn't a problem for the US because they are buying Eclipses that have 4130 frames. Nobody seems to have picked up on the fact that if they don't know how to weld stainless there's a pretty good chance they don't know how to weld 4130 either.

I'd start a list about the problems with the Eclipse but I learned my lesson with the "Resonance" thread.

Mike G

I feel learning about a gyroplane accident and why something failed has value for me.

I feel sharing what I have learned has value even if people don't respond or disagree.

In my opinion the participants on the Rotary Wing Forum care about a fatal accident and a flight critical part failure.

A lack of response on a thread may indicate that people felt they had nothing to contribute to the discussion beyond an emotional response.

I care deeply about gyroplane safety and work to make flying gyroplanes safer.

Some of my life's experience gives me insight into weldments and structures.

I feel the failure of the ELA tail boom was a combination of poor design and poor welding technique.

I do not have an opinion on what it will take to improve ELA's welding or precisely how to improve the design.

In my opinion the proper stainless steel alloy is a satisfactory material for a properly designed and fabricated gyroplane airframe.

It would not be my first choice.

In my opinion 4130 will not solve design and fabrication issues and in some cases may exacerbate them.

 

[chrisk]

My lack of response has a bit to do with not reading French. --It's a bit painful to run it through a translator and get the proper context. Figure 4 seems to be a different ELA-07. And I know enough about welding to know that top plate is an ugly weld. Figure 2 and 3, show the failed parts on this gyro. The text suggest bad welding technique and fatigue. This may have been difficult to spot on a pre-flight, and may have only been picked up on a thorough annual inspection. My conclusion is the manufacturing had a quality control issue and the design is likely marginal, which when combined cause a fail. And given the history of at least one other ELA-07 cracking in this location, the equivalent of an Airworthiness Directive is probably appropriate. If I owned an ELA-07, I'd be calling the factory for the fix. I suspect the fix would be cheek plates welded to each side of the structure extending 6 or so inches past the suspect area.

I didn't catch how many hours were on this gyro. Does anyone know?

 

[Abid]

Steve
You're wasting your time, we discussed it here:

https://www.rotaryforum.com/forum/ro...esonance/page3

and nobody was interested.
The conclusion seems to be that since the only members who talked about it were one owner, of debatable technical competence, and a competitor to ELA there was nothing to discuss and that it doesn't matter if the frame cracks because of lousy welding, you will pick it up in a thorough pre flight.

It was also said that ELA's terrible stainless steel welding quality isn't a problem for the US because they are buying Eclipses that have 4130 frames. Nobody seems to have picked up on the fact that if they don't know how to weld stainless there's a pretty good chance they don't know how to weld 4130 either.

I'd start a list about the problems with the Eclipse but I learned my lesson with the "Resonance" thread.

Mike G

Hi Mike G:

It was me who said that most ELA in the US are E-10 that have Chromoly (4130) and carbide precipitation is not an issue there. But I want to be clear, that its clear to me ELA has a serious issue with QC and they need to figure out extent of the problem and release a serious safety bulletin with a solution other than inspection for cracking that BEA has determined is happening from inside to outside. That's my opinion.

Look, I can tell you this much. On AR-1 the tail section is not a joint like ELA and that we are back purging AR-1 frames so when you shine a light inside in the welded mast assembly before it gets welded to the lower keel tube assembly, you will find nice color suggesting good penetration but no sugaring. It costs more in both Argon and in waiting time to make sure oxygen disappears from the area to weld with back purging but I obviously think its important and we are doing it.
But I understand your point, these are not visible shiny things or processes. People care more about that than stuff like this. Nonetheless its important.

So I absolutely did not mean to dismiss your concerns but you have to understand my position. We manufacture another gyroplane.
We can all have problems from time to time. The main thing is how do you handle that problem and do good COS (Continued Operational Safety). I did BTW inform one of the owners of ELA company of that thread. I know him and he seemed to be a nice guy and I hope he will push to do right. So all I can say is that he must have or at least should have read it. My concern is with safety of gyroplanes and having no further preventable fatal accidents regardless of the pain and anger that a manufacturer may have to endure from the fleet to get things right.

 

[DavePA11]

Mike G,

What is the list of issues with the Eclipse? When I read about potential issues with different gyros on this forum I review if the issue is present with the gyro I fly to make sure I don’t run into the same issue. I certainly spend more time reading than posting.

Thanks,

Dave

 

[perbgyro]

Stainless, cracks, welds, 100hr required inspections.... I have less worries in flight... two numbers 6061 and 4130...

 

[Abid]

Here is an example on our tubing of how when we do a full penetration weld with purging (right side) and when we do the same without back purging (left). There is no magic here. Just good process and good welding control. Butt joints require full penetration welds to get full strength and ELA dues use them on their frame at multiple points including the tail triangle and has no gusset.

 

[Kolibri]

fara, below is a Calidus 83-AMW which saw a mast breakage from its crash.
The interior of the weld is able to be seen.

 

[Abid]

Yes I know this whole story and have seen these pictures and more before. This has nothing to do with mast being stainless steel technically

 

[Kolibri]

I thought it showed a lack of back purging.

 

[XXavier]

Yes I know this whole story and have seen these pictures and more before. This has nothing to do with mast being stainless steel technically

The canopy opened on takeoff. Photos and comments, including an account from the pilot -–in French-– here: http://www.forum-autogire.com/t2277-...IDUS-83AMW.htm

 

[Tomgyro]

It is my opinion that the only way for Sportcopter as a company to keep its former reputation as a trustworthy manufacturer with dependable information coming forth is for Jim himself to come forward on this forum and publicly denounce, distance himself from and disavow any connection with, partnership or relation to the person who is making all of these claims on behalf of Sportcopter. Or Jim can agree to all of the claims being made in this post and the host of other posts on this forum as coming from Sportcopter. This public choice to back up or deny the claims being made about his product will allow those not familiar with gyros, the gyro community, the many other gyro manufacturers to weigh the value of the claims and dispersions being made.

 

[Kolibri]

Jim posted this in another thread:

As this thread's originator has stated, his posts reflect solely his own personal views and do not constitute any marketing effort or claims on behalf of another.

Sport Copter is committed to it's tradition since 1957 of quality, strength, performance safety, and longevity. We are excited to soon be offering new models such as our 2-place Vortex M2, made here in the USA.

Thanks to all who stopped by to visit us at the 2018 AirVenture. I missed Mentone unfortunately due to a pre-trip injury, but look forward to flying there next year! Meanwhile, stop by and see us at the Scappoose, Oregon Airport (SPB) if you're ever in the Pacific NW!

Tomgyro, you can cease calling me a liar now.

Kolibri

 

[Tomgyro]

Duly noted

 

[Kevin_Richey]

The canopy opened on takeoff. Photos and comments, including an account from the pilot -–in French-– here: http://www.forum-autogire.com/t2277-...IDUS-83AMW.htm

Google translate provided Rene Brun's report on the french autogire forum of how far half of one rotor blade flew after crashing:

"The shiny piece is a half of blade which detached itself by tapping the ground or the apparatus, it was found at 200m.
I saw the canopy open trying to extend the left arm to close it but it was impossible, I always piloted the aircraft in a straight line at takeoff, it was still stable and just after bringing my left arm j ' I heard a kind of bang and then I found myself in the emergency ambulance, I have no memory of this trajectory to the ground. the first person who came running to help me saw me coming out of the gyrocopter and collapsed 4 to 5 meters from the aircraft.
I only have this little video to show me the trajectory.

In the last pictures before the impact I see the mast tilted to the right a rotor blade taps the right wheel and breaks the train blade, the blade breaks in two a piece is ejected at approx. 200m."

Sobering. More than 600'.

 

[Kolibri]

I suspect they have improved their process and quality assurance since this accident since I have not heard of any other failures and only one crack.
It appears to me there are lots of ELAs flying around.

I think they've a horrible record.

Just yesterday I was discussing tail boom failure in a high thrust line gyroplane with a client and our conclusion was as long as the power was reduced and the empennage didn't reach the rotor it would be survivable if there wasn't a fire.

From the description of the accident the pilot may have left the power in and had a power push over.

Such implies that if power were reduced after losing the tail boom, that a PPO could be avoided.
It is my opinion that any power left in while and after (for even a moment) losing the tail will result in a PPO.
The only conceivable way for a lost tail boom not to buntover the airframe is if power were zero beforehand.
So, I think this is an inaccurate and irresponsible conclusion.


_________
Just to clarify, the above post was about the Calidus 83-AMW.
Thanks for the new info, Kevin, although I expect some folks to scoff, "OK, one time a broken blade was thrown a long distance!"
And if you mention the two ELA 07s (A12FOB and N534EA), they'll reply, "OK, only three times have broken blades been thrown a long distance!"

Regards,
Kolibri