PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Rotorheads (https://www.pprune.org/rotorheads-23/)
-   -   EC 120 Rollover in Germany (https://www.pprune.org/rotorheads/495153-ec-120-rollover-germany.html)

skadi 10th Sep 2012 05:31

EC 120 Rollover in Germany
 
A EC120 rolled over during T/O at an airshow in southern Germany. Pilot and PAX ok, but one spectator died after beeing hit by debris, two others injured.

Pictures of the crash:

Ein Toter bei Unglück auf dem Flugtag in Metzingen | Südwest Presse Online

skadi

idle stop 10th Sep 2012 07:16

Very sad. Condolences to the family of the person killed, and wishing a speedy recovery to those injured.
There have, I believe, been 3 notifed mishaps with the EC120 involving a spot turn (one, I think, was untintentional and in gusty conditions) in the hover.
The EC120, like many helicopters, requires a fair amount of fore/aft cyclic input during the manoeuvre to retain a stable pitch attitude, and these control inputs are exacerbated by increasing surface wind speeds.
For an aircraft that hangs right skid low in the hover, the roll attitude increases noticeably with a crosswind from the right.
After the previous occcurrence, EC issued a Service/Safety Letter(?) reminding pilots that they must fly with some cyclic pitch applied at all times. I certainly find that this reduces my own tendency to overcontrol in roll in the hover...and I have fair amount of time on the type!

Senior Pilot 10th Sep 2012 07:26

Images from the newspaper report:

http://www.swp.de/storage/scl/bilder...8_II0A7085.jpg

http://www.swp.de/storage/scl/bilder...3_II0A7086.jpg

http://www.swp.de/storage/scl/bilder...4_II0A7087.jpg

http://www.swp.de/storage/scl/bilder...0_II0A7088.jpg

idle stop 10th Sep 2012 07:49

Splot: You omitted the earlier ones which show the sequencing: spot turn commencing and the rear right hand skid blade digging in. As the images are stills, no idea what the rate of turn was.
The photos you posted make it look like there's a down-slope towards the crowd line. More difficult to see on the earlier photos in sequence, so may be lens distortion; but if aircraft was pointing downslope when the skid balde dug in, the slope would not have been in the pilot's favour!

Senior Pilot 10th Sep 2012 08:36


Originally Posted by idle stop (Post 7405888)
The photos you posted make it look like there's a down-slope towards the crowd line. More difficult to see on the earlier photos in sequence, so may be lens distortion; but if aircraft was pointing downslope when the skid balde dug in, the slope would not have been in the pilot's favour!

Looks like a downslope, but the photo horizon isn't level in all the images, either:

http://www.swp.de/storage/scl/bilder...7_II0A7042.jpg

toptobottom 10th Sep 2012 09:02

Half of the 34 images are of post-incident activities. These few are worth posting however:

http://www.swp.de/storage/scl/bilder...ion=1347211384

http://www.swp.de/storage/scl/bilder...ion=1347211368

http://www.swp.de/storage/scl/bilder...ion=1347211353

http://www.swp.de/storage/scl/bilder...ion=1347211337

http://www.swp.de/storage/scl/bilder...8_II0A7085.jpg

The images posted by Splot were clearly taken with a motor-drive; it looks as though the pilot had completed the spot turn, descended to a very low hover, then (judging by the aircraft's position in relation to the background and nose up attitude) he was crabbing and/or flying backwards into the up-slope. The r/h skid caught terra firma and over you go :eek:

A fast shutter speed was used, so it's also difficult see what the wind was doing, but those flag things in the background seem pretty calm to me...

John R81 10th Sep 2012 14:57

My condolences to the family of the deceased, and I hope that the injured recover soon. Very sad to see any accident with injuries or fatalities.

TTB - I think your set of photos are better for understanding what may have happened. There is no suggestion of any wind strength, and the spot-turn seems to have been completed without a problem. I also think that the photos suggest sideways flight, unless we assume that the photographer ran several meters to his left to change the angle on the end of the tent in the background. Tipping the photos to level the horizon does suggest a small rearward component to the flight.

Catching a skid with sideways movement in that direction is most likely not going to end well, regardless of the make. Coincidence that there is another thread running with a Bell catching its left skid during a spirited departure. http://www.pprune.org/rotorheads/243...ml#post7405850



It does look like low-speed CFIT.

skadi 10th Sep 2012 16:25


I also think that the photos suggest sideways flight, unless we assume that the photographer ran several meters to his left to change the angle on the end of the tent in the background.
If you check the alignement of the righthand lower corner of the red roof and the top right corner of the white truck parked in front, its the same on all photos. So one could assume no significant change of the position of the photographer.

skadi

AnFI 10th Sep 2012 16:55

LTE(ducation) ?
 
Judging from the frame rate in the accident sequence - the yaw rate in the pre-accident sequence is very high - if they are shot at the same intervals.

Loss of control following high yaw rate?
or
Slope illusion giving impression of greater skid/ground separation?

hillberg 10th Sep 2012 18:10

A pilot who flys beyond his personal limits causes problems-Be safe.

nellycopter 10th Sep 2012 18:23

What a strange comment hillberg ......

toptobottom 10th Sep 2012 18:48

It seems to me that the frame rate during the crash sequence was at least 4-5 fps, but not so during the spot turn (he would have been doing appx. 320rpm if so!). It appears the spot turn was successfully completed when the aircraft is pointing to the left. The pilot is clearly in control at that point, but for inexplicable reasons, then descends into a very low hover, before manoeuvering backwards and striking the ground.

John R81 10th Sep 2012 21:48

Easy to do that. On my SLR, press the button for one shot, press and hold then it is set 5x per second.

toptobottom 10th Sep 2012 23:49

John - didn't know you had the merc as well as an EC120 :ok:

RVDT 11th Sep 2012 17:33

If it was level ground he may have got away with it as the aircraft possibly would have kicked around and yawed.

But as the "heel spring" and the "tail bumper" both seem to grab the ground at the same time................................not pretty!

Andy_RR 12th Sep 2012 22:26

I was at the air show and heard the crash (was walking away from the scene at the time). Turned around to see the helicopter lying on the ground and bits flying everywhere. It was a frightening noise and very sad to learn of a fatality.

Rossfeld is a very hilly grass field on top of a big hill. Most of the runway is steeply sloped onw way or the other. You certainly can't see one end of the runway from standing at the other.

It's a fantastic venue for an air show since the displays can take place at spectator eye level over the valley. I do hope this doesn't mean the end of the event.

The day was beautiful and sunny with hardly a breath or wind. Aircraft were landing in both directions at various times during the event.

Edit: I should add that this didn't appear to me to be a take off accident in a sense, because I believe this was one of the Rundfluege which were departing from and returning to the (other, not shown) far end of the field. What the helicopter was doing and why hover taxiing near where the accident took place is unclear. It would have had to taxi up and down the middle hill of the runway quite some distance to get there as far as I can figure. There might be an operational reason for this but it seemed weird and unnecessary to me

skadi 3rd Oct 2012 07:51

Video of the crash:



skadi

Paddyviking 3rd Oct 2012 08:18

I think the video is self explanitory, it puts an end to any speculation !

Pv

Nubian 3rd Oct 2012 08:53

Is this another "student-pilot'' flying sightseeing at an airshow, like the Longranger in the video-thread?

By the general handling of the machine, I would not send this guy solo!!!

Both accidents involving sightseeing/demo flights, and rollovers during taxi/take-off due to poor handling of the machine.

misterbonkers 3rd Oct 2012 09:33

Low time pilots are cheap to employ.

Most have just learnt on R22s - many of whom have been taught to hover around very low (1 guy was told 2ft max!) 'in case the engine quits' - something I disagree with and always say it increases risk of clipping something whilst manoeuvring.


All times are GMT. The time now is 15:44.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.