Resonance...?

Alan_Cheatham;n1127918 said:
XXavier, when was your ELA manufactured? Also, if it’s not too much trouble could you post some pictures of the tail boom reinforcements the factory installed, I would like to compare them to a ELA we have here.

It was delivered to me on June 2017. I'll make the photos soon. I think that ELA has already informed of all this, through maintenance bulletins...
 
The tail failure in France was in 2015. Here CN 2017-ULM-01 - ELA07.pdf
is the DGAC (French FAA, CAA) directive that instructs all owners of ELA 07 type gyros to carry out an inspection of the tail boom at the welds under the prop before the next flight or the aircraft is grounded, it then says to carry out the inspection every 4 months or 100 hours afterwards.

And here BEA2015-0318.pdf is the French BEA (Bureau of investigation) report into the fatal crash in June 2015. The conclusion is pretty damning.

Two failures at the welds due to fatigue. ELA tail boom failure 1.jpg
ELA tail boom failure 2.jpg



« Les examens visuels et métallographiques ont mis en évidence de nombreux défauts de soudure : irrégularités, surépaisseurs, excès de pénétration, manque de pénétration, rochage, projections métalliques. Les défauts les plus pénalisants (manque de pénétration, rochage et excès de pénétration) se situent à la racine, c'est‑à-dire à l'intérieur des profilés. La majeure partie des longueurs soudées en zone A et en zone B présentent un ou plusieurs de ces défauts.”
Unofficial Translation
The visual and metallurgical examinations showed evidence of numerous welding defects:
Irregularities, over-thickness, excessive penetration, lack of penetration, root porosity (also called sugaring or cauliflowering), metal spatter. The weld defects that penalise the most (lack of penetration, root porosity and excessive penetration) were situated at the root, i.e. on the inside of the tubes. The major parts of welds in zone A and B included one or many of these defects.
The report goes on to say that in July 2015 there was another ELA involved in an accident where the tail boom failed. A subsequent investigation of the tail boom showed the same weld defects. Spontaneously another ELA owner sent pictures of his failed tail boom. (the welds in this photo are a disaster, I doubt if they were done by ELA).

ELA issued a Service bulletin 19 ( Service-Bulletin-Nº-07-019-ENG.pdf ) in Dec 2015 stating:

"It is difficult to know the reason of the apparition of that crack. We think it could happen due to bad
operation, modification of the original configuration, rudder flutter events or high rotor vibrations.
Whether for whatever reason, we have decided to issue this “Service Bulletin Nº19” to alert all
users to inspect the area in question and thus ensure the safety of our gyroplanes."

If it wasn't so tragic, their "it is difficult to know the reason" would be laughable. They knew only too well what the cause was, lousy welding, no backing gas when TIG welding stainless and non-existent quality control.

ELA quietly put this on their website and say it is up to the owners to remain informed. Their website hasn't functioned correctly since at least July 2017 when I asked why I couldn't download copies of the Bulletins and I still can't download all of them today. So how are owners supposed to stay informed?????

Mike G CN 2017-ULM-01 - ELA07.pdf BEA2015-0318.pdf
 

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And another issue

​​​​​​http://www.seguridadaerea.gob.es/med...a_01_13_en.pdf

Here's the description from the Spanish Authorities:

​​​​​​"As a result of breakage of the hub bar in the area of blade attachment in a microlight gyroplane manufactured by ELA AVIACIÓN S.L., model: ELA-07 R-100 during flight broke away a blade together with a part of the hub bar to which was attached. The "Comisión de Investigación de Accidentes e Incidentes de Aviación Civil" (CIAIAC), has established that the cause for which the blade was broke away in-flight, has been produced by a fatigue process, favoured by some holes counterbores on the underface of the piece. It also has joined the fact that the piece has not manufactured with the material detailed in the drawings of project, specified by the manufacturer."

ELA put out Bulletin SB 16 regarding this, but this SB states in its description:

"The CIAIAC (civil aviation accident and incident investigation commission) in collaboration with AESA (Spanish agency for aviation safety) have determined that: In the case of non-proper use, storage, inspection and maintenance of the gyro, there is an area in the hub bar where some cracks can appear during operation. This area is located in the lower face of the hub bar, where the bolts heads are inserted in a machined groove. Non-compliance with this service bulletin may cause the total collapse of the rotor in flight and therefore the loss of life of the pilots."

My highlighting in red.

Reading the above looks like two parallel realities.

And we haven't even touched on the subject of the melting fuel tanks..
 
helipaddy: that problem of the hub bar was solved with a new design. Most (if not all) ELA gyros have been fitted (or retrofitted) with the new hub bar, that has been standard issue for at least five years.
 
XXavier
Yes it has been sorted with the new 145C hub bar. But after buying a 154B bar for a different SB, and then buying a 145C hub bar for our machine, I'm hoping this hub bar and teeter block is made correctly with the material specified in the type approved drawings
 
XXavier;n1127927 said:
It was delivered to me on June 2017. I'll make the photos soon. I think that ELA has already informed of all this, through maintenance bulletins...

Yes and we’ have kept up with the service bulletins but they only instruct to carry out scheduled inspections for cracking. My interest is for any information on changes ELA is now applying to the production of their airframes to address the potential issue.
 
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Alan
How are you keeping up with service bulletins? The ELA website has hardly worked since at least July this year. On the odd occasion that it works when you go to download the bulletins there is only one that downloads each time.

ELA is a shambles, they can't even get a simple website to work properly so that owners can check what the latest engineering/fabrication/QA screw-up is to see if they should be flying or not.

Mike G
 
Wow I was only aware of the mast welding cracks bulletin for ELA gyros from Australian clubs
 
Mike G;n1127928 said:
The tail failure in France was in 2015. Here CN 2017-ULM-01 - ELA07.pdf
is the DGAC (French FAA, CAA) directive that instructs all owners of ELA 07 type gyros to carry out an inspection of the tail boom at the welds under the prop before the next flight or the aircraft is grounded, it then says to carry out the inspection every 4 months or 100 hours afterwards.

And here BEA2015-0318.pdf is the French BEA (Bureau of investigation) report into the fatal crash in June 2015. The conclusion is pretty damning.

Two failures at the welds due to fatigue.




« Les examens visuels et métallographiques ont mis en évidence de nombreux défauts de soudure : irrégularités, surépaisseurs, excès de pénétration, manque de pénétration, rochage, projections métalliques. Les défauts les plus pénalisants (manque de pénétration, rochage et excès de pénétration) se situent à la racine, c'est‑à-dire à l'intérieur des profilés. La majeure partie des longueurs soudées en zone A et en zone B présentent un ou plusieurs de ces défauts.”
Unofficial Translation
The visual and metallurgical examinations showed evidence of numerous welding defects:
Irregularities, over-thickness, excessive penetration, lack of penetration, root porosity (also called sugaring or cauliflowering), metal spatter. The weld defects that penalise the most (lack of penetration, root porosity and excessive penetration) were situated at the root, i.e. on the inside of the tubes. The major parts of welds in zone A and B included one or many of these defects.
The report goes on to say that in July 2015 there was another ELA involved in an accident where the tail boom failed. A subsequent investigation of the tail boom showed the same weld defects. Spontaneously another ELA owner sent pictures of his failed tail boom. (the welds in this photo are a disaster, I doubt if they were done by ELA).

ELA issued a Service bulletin 19 ( Service-Bulletin-Nº-07-019-ENG.pdf ) in Dec 2015 stating:

"It is difficult to know the reason of the apparition of that crack. We think it could happen due to bad
operation, modification of the original configuration, rudder flutter events or high rotor vibrations.
Whether for whatever reason, we have decided to issue this “Service Bulletin Nº19” to alert all
users to inspect the area in question and thus ensure the safety of our gyroplanes."

If it wasn't so tragic, their "it is difficult to know the reason" would be laughable. They knew only too well what the cause was, lousy welding, no backing gas when TIG welding stainless and non-existent quality control.

ELA quietly put this on their website and say it is up to the owners to remain informed. Their website hasn't functioned correctly since at least July 2017 when I asked why I couldn't download copies of the Bulletins and I still can't download all of them today. So how are owners supposed to stay informed?????

Mike G CN 2017-ULM-01 - ELA07.pdf BEA2015-0318.pdf

There is no way that Figure 4 on BEA2015-0318 report are from ELA. Those just look to be even visually horrible welding with a doubler plate on top by someone else, right?
Usually operations like welding are done the same way on the same areas via sometimes called special definitions process.
How many hours were on these machines Mike G? Can you tell me from the report.
 
There was a second ELA fatality in 2015, the month after the one I reported earlier. Attached is the French BEA report and below an unofficial translation.

A further investigation showed that this ELA had the same weld defects as the June fatality.

ELA clearly have a major problem with their frame design and fabrication especially their welding procedure.

Mike G

Unofficial translation of BEA report


1 – THE FLIGHT
A witness, also an ULM pilot, heard the gyroplane coming from the North East. He saw it arriving on finals for 27 then make a low overshoot at two or three meters height. The gyroplane then turned left downwind at
about 70 meters. The pilot waved to him with his hand and then at the end of the down wind leg he climbed and turned left. At that moment, the witness clearly saw the blades of the rotor and heard a sound that he associated with "flapping". He then saw the gyrocopter roll sharply to the left then fall vertically. On the ground the aircraft caught fire.
2 - ADDITIONAL INFORMATION
Examination of the wreckage at the accident site did not highlight any particular failure. However the rotor head and a cyclic pitch control rod were ruptured and were taken for further examinations. The rotor head did not have any sign of a pre-impact failure. The connecting rod end broke by overload during the impact of the gyroplane with the ground.
A main rotor flap in flight is characterized by a sharp rise in the advancing blade (and a descent of the retreating blade). This movement causes generally the deformation of the stops of the blades and sometimes also the interaction of the main rotor blades with propeller blades. No signs of blade flapping were seen.
The 63-year-old pilot held a private pilot license and a glider pilot license. He had more than 800 flying hours. He also held
a ULM pilot license since 1993.
Estimated weather conditions at the accident site:
West wind 5 to 10 kt;
Visibility greater than 10 km;
BKN 4,500ft;
Temperature 26 ° C.

Abnormal vibrations were reported by the pilot, who had complained to the manufacturer of a rotor vibration problem. Despite adjustments made by manufacturer , the vibrations had not disappeared. No element allows this problem reported by the pilot to be related to the accident.The witness states that he had discussed with the pilot who was aware of the problems of rotor flapping induced by rapid action on the control column.
3 - LESSONS LEARNED AND CONCLUSION
The fall of the autogire was probably caused by a decrease in the rotor rpm. The investigation did not determine the cause of this loss of rpm.
 

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Fara
As I wrote in my post, I don't think those welds were by ELA, they're lousy welders but even they aren't that bad. I don't know where you imagined there was some "special definitions process" with ELA you'd be lucky to get the stiffening plates out of them without having to pay.

No idea of the age or number of hours on either machine. I searched on the old French forum but these crashes were hardly discussed at the time.

Mike
 
Mike G;n1127967 said:
Fara
As I wrote in my post, I don't think those welds were by ELA, they're lousy welders but even they aren't that bad. I don't know where you imagined there was some "special definitions process" with ELA you'd be lucky to get the stiffening plates out of them without having to pay.

No idea of the age or number of hours on either machine. I searched on the old French forum but these crashes were hardly discussed at the time.

Mike

I see. Do you have any pictures of their stiffening plates Mike and where are they supposed to get installed.

What about the hub bar or blade failure? Any report on that or did I miss it. I do remember there was an incident in Poland in an ELA and the blade left the gyro in flight and then another ELA found a crack in the hub bar. Is that what you are referring to or is it outside of Poland.
 
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Mike G;n1127961 said:
Alan
How are you keeping up with service bulletins? The ELA website has hardly worked since at least July this year. On the odd occasion that it works when you go to download the bulletins there is only one that downloads each time.

ELA is a shambles, they can't even get a simple website to work properly so that owners can check what the latest engineering/fabrication/QA screw-up is to see if they should be flying or not.

Mike G

Mike,

ELA did revamp their web site and had some teething problems but we've been able to log in and download the bulletins and manuals for a few months now. Just before posting this reply I tested their site again just to make sure and was able to log in and download several pdf's. I did find a couple of links that were broken but was able to fix them, if the link URL contains "choco.weberizate.es" replace that part with "www.elaaviacion.com" and it should work then.
 
No Title

After reviewing the documents of the failed tail boom I can say that the 2014 ELA G8 we have here in the US has additional reinforcement plates at the boom splice, so apparently ELA felt the need to reinforce this area at some point in the past. But, I would like to examine pictures of a recently produced ELA to see if they have made any additional changes to their current production.
 

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Alan
I have been complaining to ELA since July about their website. This morning it still wouldn't work I got "127.0.0.1 site not authorized" . Looking through the internet someone proposed switching off Skype and that did it.
The download page has changed from when it worked (why did it work once and then never again????) the other day, there are no more little Spanish and English flags for the translations.
I note that the Scorpion, their new 07S has all the same Bulletins as the 07 Cougar. That doesn't make sense, surly they fixed the problems when they designed the Scorpion???

I see they've also changed the parts list, instead of exploded drawings showing where the parts go you just get a series of tiny photos with part numbers and it's up to you to work out which part is which, not always easy when looking at a bolt.

Mike G
 
The ELA I mentioned earlier that the owner (also instructor and ELA dealer) complained had a tail flutter problem is only 1 year old with 150 hrs and the cracks he found in the tail boom weren’t in the same place as those mentioned in the report. His were at the weld just in front of the tail (see photos).

20171006_161740.jpg

I was also told that when he complained about the tail flutter he finally managed to get ELA to supply a new rudder and he reckons that the new one has a different internal structure (change of CofG???) and he says the hinges are offset. However the fixture for the rudder cables was different and ELA insisted that he paid for the new rudder cable to match the new rudder. Apparently it has resolved his problem but he says he’ll never sell another ELA 07 to any of his customers and he has serious concerns about the Eclipse.

This crack after only 150 hours is frightening and ELA's insistence that the customer PAYS for the repair parts is to be born in mind if you're thinking of buying an ELA.

The ELA chassis seems to be work in progress, from its conception, every now and then they issue an new bulletin telling you to look for more cracks and to weld a patch on them.

It's clear that ELA know they have a problem with the rudder and flutter and vibration because they had the solution available for this gyro. They also should have realised that the cracks being reported are probably linked to the vibration and probably bad welding but they continue to let owners fly and hope that they have checked the website (that crashes often) regularly to realise that they should be looking for cracks. Since the website and the bulletins are only in Spanish and some in English there's a good chance that many other nationalities never get to read them.

Mike G
 

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It looks to me that the welds did not fail,it was the metal on either side of the welds, the metal got hot from the welds and lost its strength.

Thats what happens when the wrong metal is used for the job.It appears that the vibration from the tail concentrated at the junction of the two tubes.

I have seen fixed wing planes have vibration problems like that.
 
Rudder flutter would happen also if the tension in the rudder cables is not maintained. The tension we specify is 40 to 45 pounds. Its easy enough to adjust the tension via the turnbuckles. It should be checked every 50 hours or in pre-flight simply by feel. I also recently saw that people don't tend to clean their pulleys on which rudder cables run. They should be kept clean or expect fraying in cables.
 
fara;n1128040 said:
Rudder flutter would happen also if the tension in the rudder cables is not maintained. The tension we specify is 40 to 45 pounds. Its easy enough to adjust the tension via the turnbuckles. It should be checked every 50 hours or in pre-flight simply by feel. I also recently saw that people don't tend to clean their pulleys on which rudder cables run. They should be kept clean or expect fraying in cables.

Thanks for the hint. Another club member has lent me a tensiometer, and I'll check that tension soon...
 
Be sure to set the tension for your aircraft Javier; it may not be the same as the AR1.

It should be called out in the POH for your aircraft on the maintenance manual.
 
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