Fatal - ELA Aviacion ELA-07 EC-EZ1, Camarenilla, Toledo, Spain 08 AUG 2018

[TyroGyro]

Accident ELA Aviacion ELA-07-R115 EC-EZ1,

After the takeoff, when it was approximately 1.6 km away from the aerodrome in prolongation of the runway axis, it fell on the ground and caught fire.The pilot died in the crash. The inve...

aviation-safety.net

After the takeoff, when it was approximately 1.6 km away from the aerodrome in prolongation of the runway axis, it fell on the ground and caught fire.The pilot died in the crash.
The investigation was unable to determine the cause of the accident.

FINAL REPORT: https://www.mitma.es/recursos_mfom/comodin/recursos/ulm_2018_016_a_eng.pdf (official English translation)

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"1.5. Personnel information​

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The instructor who trained him reported that they had flown on paramotor aircraft before, but that he was not registered when he started to fly autogyros.​

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He also reported that he did not let him fly solo for a long time because he was not proficient in handling the aircraft and did not know the procedures well. He also commented that he had done fairly well on the exam to obtain his license and that he had 40 h of experience (including training hours), including 6 h on the accident autogyro."​

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"2. ANALYSIS​

In these aircraft, tilting the rotor backward raises its revolutions, and therefore the lift. This is referred to in aviation jargon as “loading the rotor”.​

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It may be that the rotor was tilted forward somewhat, and therefore “unloaded”, meaning it was not generating enough lift.​

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The fact that the blades were practically intact could also indicate that the RPM were not sufficient to keep the aircraft aloft...​

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The above notwithstanding, investigators were unable to determine the cause of the accident."​

Condolences, etc.

 

[Tyger]

Puzzling:
The evidence found at the crash site indicates that the impact with the ground was practically vertical...
This is confirmed by the deformation of the main gear spring, which was practically flat, and the condition of the tail supports.

The good condition of the rotor rocker droop stops indicates that there was no mast bumping caused by unloading of the rotor (loss of lift) as a consequence of an instantaneous negative acceleration.
The blades were practically intact...

A study of the engine reliably concluded that it did not fail prior to the accident, meaning it was supplying power and that all of the damage found was a result of the impact.

 

[loftus]

Hmmm - medical event?

 

[Tyger]

What kind of trim system do ELAs have?

 

[BEN S]

it's possible no matter how silly it seems that he was practicing "spot" landings from a vertical decent and was not aware of the decent rate. I know when I first started doing vertical descents it sure seemed slow enough to land that way, but rather then just try it, I asked the manufacturer. He of course told me the actual speed I was dropping at and that I would probably survive it, but the rig sure wouldn't.
What if the pilot in question didn't think to ask and tried to land a vert decent, the rig took the hit, but ruptured the tanks and he burned?

just a theory.

 

[Tyger]

That's conceivable, but if you really wanted to try something like that, wouldn't you rather be above the airport, where you could take off again if such a landing were successful?
Crashing/landing a mile away makes it seem unintentional. Could he have had some sort of runaway trim?

 

[Vance]

It is my observation that in the hearts of many aspiring gyroplane pilots is the belief that the cyclic is the up lever even when they understand intellectually that the throttle is for altitude and the cyclic is for airspeed.

It is counterintuitive to point the noise at the ground when it is rushing up at you and I have had clients freeze up when practicing recognition and recovery from low airspeed and a high rate of descent.

 

[Doug Riley]

There have been fatal gyro accidents in which a pilot attempting an off-field landing misjudges his altitude and flares significantly too high (or fails to flare at all). A too-high flare has the effect of a vertical descent to the ground. The resulting impact is plenty severe enough to rupture a fuel tank.

Some terrain is so smooth and uniform that it's hard to judge your exact height. Smooth water is notorious for this, but even smooth grass is pretty featureless.

Two fatal accidents that may have been caused by this phenomenon come to mind. One happened in the Midwest, and involved a Gyrobee (sorry I don't recall the pilot's name). The other took the life of Casey Stiles, the professional heli pilot and instructor who signed off my BFI.

 

[Burrengyro]

What kind of trim system do ELAs have?

Pneumatic trim on pitch. Manual trim on roll in my ELA07S. If the trim fails, it just means you need more muscle to move the stick back which can be tiring if the flight is longer than 30 minutes. Trim micro circuit breaker trips out if you have an earth short circuit in the trim switch wiring. I also had a bad connection to a relay connected to the trim switch on the stick which in turn caused the trim micro circuit breaker to trip regularly until I found the cause.

 

[Brian Jackson]

There have been fatal gyro accidents in which a pilot attempting an off-field landing misjudges his altitude and flares significantly too high (or fails to flare at all). A too-high flare has the effect of a vertical descent to the ground. The resulting impact is plenty severe enough to rupture a fuel tank.

Some terrain is so smooth and uniform that it's hard to judge your exact height. Smooth water is notorious for this, but even smooth grass is pretty featureless.

Two fatal accidents that may have been caused by this phenomenon come to mind. One happened in the Midwest, and involved a Gyrobee (sorry I don't recall the pilot's name). The other took the life of Casey Stiles, the professional heli pilot and instructor who signed off my BFI.

I believe it may have been Alan Coates. Reports are that he came in nose first. Seems the exact cause is still a mystery but is consistent with this narrative.

 

[Tyger]

Pneumatic trim on pitch. Manual trim on roll in my ELA07S. If the trim fails, it just means you need more muscle to move the stick back which can be tiring if the flight is longer than 30 minutes. Trim micro circuit breaker trips out if you have an earth short circuit in the trim switch wiring. I also had a bad connection to a relay connected to the trim switch on the stick which in turn caused the trim micro circuit breaker to trip regularly until I found the cause.

OK, I was wondering if perhaps he encountered full back trim, making it difficult to put the stick forward, engendering an unexpected vertical descent.

 

[Burrengyro]

OK, I was wondering if perhaps he encountered full back trim, making it difficult to put the stick forward, engendering an unexpected vertical descent.

You always go from "brake" to "flight" mode on the pneumatic selector and dump all residual air in the system before pre-rotating in an ELA07 type gyro so that the stick can be brought aft without restriction once 220 rotor rpm has been achieved by the pre-rotator prior to takeoff roll. However, if the pilot makes the mistake of not going from Brake mode to flight mode, it is possible that full normal rotor rpm will not be achieved during the takeoff. You quickly realize there is a problem because takeoff takes longer and also because the stick is more difficult to bring fully back for the takeoff run because the "brake" mode air pressure has not been released. The gyro will lift off (especially if flying solo) but if the stick is pushed forward in this scenario to gain airspeed, the still engaged rotor brake could slow the rotor to a dangerously low rpm. I have to admit I made this mistake at least once and quickly realized my error and switched to flight mode quickly which removed the braking effect "brake" mode had on the rotor rpm. Rotor rpm recovers quickly once this error is corrected. But if not corrected, the consequences might not be good.

 

[Tyger]

 

[chrisk]

You always go from "brake" to "flight" mode on the pneumatic selector and dump all residual air in the system before pre-rotating in an ELA07 type gyro so that the stick can be brought aft without restriction once 220 rotor rpm has been achieved by the pre-rotator prior to takeoff roll. However, if the pilot makes the mistake of not going from Brake mode to flight mode, it is possible that full normal rotor rpm will not be achieved during the takeoff. You quickly realize there is a problem because takeoff takes longer and also because the stick is more difficult to bring fully back for the takeoff run because the "brake" mode air pressure has not been released. The gyro will lift off (especially if flying solo) but if the stick is pushed forward in this scenario to gain airspeed, the still engaged rotor brake could slow the rotor to a dangerously low rpm. I have to admit I made this mistake at least once and quickly realized my error and switched to flight mode quickly which removed the braking effect "brake" mode had on the rotor rpm. Rotor rpm recovers quickly once this error is corrected. But if not corrected, the consequences might not be good.

Well, this is consistent with the accident report.

 

[Mike G]

You always go from "brake" to "flight" mode on the pneumatic selector and dump all residual air in the system before pre-rotating in an ELA07 type gyro so that the stick can be brought aft without restriction once 220 rotor rpm has been achieved by the pre-rotator prior to takeoff roll. However, if the pilot makes the mistake of not going from Brake mode to flight mode, it is possible that full normal rotor rpm will not be achieved during the takeoff. You quickly realize there is a problem because takeoff takes longer and also because the stick is more difficult to bring fully back for the takeoff run because the "brake" mode air pressure has not been released. The gyro will lift off (especially if flying solo) but if the stick is pushed forward in this scenario to gain airspeed, the still engaged rotor brake could slow the rotor to a dangerously low rpm. I have to admit I made this mistake at least once and quickly realized my error and switched to flight mode quickly which removed the braking effect "brake" mode had on the rotor rpm. Rotor rpm recovers quickly once this error is corrected. But if not corrected, the consequences might not be good.

On my ELA 07 if I forget to switch from brake to flight and the stick isn't fully forwards the prerotator won't engage. There is a micro switch on the pneumatic trim/brake cylinder that registers that the piston isn't in brake position.
Mike

 

[Burrengyro]

On my ELA 07 if I forget to switch from brake to flight and the stick isn't fully forwards the prerotator won't engage. There is a micro switch on the pneumatic trim/brake cylinder that registers that the piston isn't in brake position.
Mike

Hi Mike,
The MTO3 Autogyro machines have the microswitch you mention above and was introduced to prevent prerotation if the stick was not in the full forward position to prevent damage to the knuckle drives connecting the pre rotator driveshaft to the Bendix. My ELA07S was manufactured in 2006 and has the older manually operated pre rotator system so does not have this microswitch. Maybe the microswitch was introduced to ELA gyros after 2006 in conjunction with the newer "button on the stick" prerotation activator replaced the old manual system. I don't know if this is also the case with the gyro in the accident report. The manufacturer's serial number on my gyro is 09061140724. The manufacturer's serial number in the accident report was 06071610724. I don't know how ELA derive their serial numbers or if the accident machine was older than my gyro. If it was older, maybe it had the older manually operated pre rotator system which had no fail-safe microswitch to warn the pilot that the selector was still in the "brake" position.

The few times I made the mistake of not selecting "Flight" position, there was a significant underperformance of the gyro at best climb speed as compared to climb performance at the correct "Flight" selector position. If this underperformance became worse, it might cause declining rotor rpm and it might tally with the crash site distance of 1.6 miles from the runway. All this is speculation on my part based on my own ELA07S experience and may not apply to this accident. John H.

 

[TyroGyro]

The manufacturer's serial number on my gyro is 09061140724. The manufacturer's serial number in the accident report was 06071610724. I don't know how ELA derive their serial numbers or if the accident machine was older than my gyro. If it was older, maybe it had the older manually operated pre rotator system which had no fail-safe microswitch to warn the pilot that the selector was still in the "brake" position.

I believe the ELA serial numbers go:-

mmyysssvv?e

where mm=month, yy=year, sss=serial (i.e. the nth ELA machine produced), vv=model variant, ? = not sure, e=engine variant (91)2 or 4

So that would suggest the accident machine was manufactured in June 2007, as the 161st ELA produced, was an ELA 07 model, with a 914 engine...

So, about 9 months younger than yours.

 

[Mike G]

I hadn't considered that your ELA was older than mine, so what you say makes sense.
Mike G

 

[Burrengyro]

I hadn't considered that your ELA was older than mine, so what you say makes sense.
Mike G

Hi Mike, The stick position microswitch linked to the "Flight" position selector switch is a very good development. I have never had a problem with the manual pre-rotator system as it is pretty robust. I don't know what the cause of the sad accident was in Spain. Just trying to understand potential system weaknesses, especially if the accident gyro was of the older type, like mine. John H.

 

[ferranrosello]

Hi, gentlemen. I was the instructor who saw the accident from another flying gyrocopter. The accident report is good, however there are some inconsistencies because of the translation from Spanish.

The rotor blades were not twisted. This implies that the rotor was not unloaded in flight, consequently the impact was not “vertical”.

What was strange is that the blades were not broken in the crash. All the damage was because of the fire. This implies that the blades hit the ground nearly stopped

In the analysis the investigator assumes the the impact was vertical. However, this is an assumption not a fact.

The meteorological conditions were good, however the air was very turbulent (August 8th, afternoon, about 38ºC).

My assumption is that the accidented gyrocopter was flying at an extremely low altitude and the main landing gear and the impacted the terrain in a pretty pitch up position. The gyrocopter hit the ground in the edge between two terrains at different level. The level difference was about 1 meter.