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-   -   AW169 Rollover (https://www.pprune.org/rotorheads/639524-aw169-rollover.html)

Nescafe 27th Mar 2021 22:58

AW169 Rollover
 
https://www.giornaletrentino.it/cron...QaT7ZNgJYuxSOE

Released the nose wheel lock with plenty of pedal applied?


https://cimg3.ibsrv.net/gimg/pprune....857cdb7f3.jpeg
https://cimg4.ibsrv.net/gimg/pprune....3b7e420b6.jpeg
https://cimg5.ibsrv.net/gimg/pprune....e6bc6482c.jpeg
https://cimg6.ibsrv.net/gimg/pprune....ff6d10d03.jpeg
https://cimg7.ibsrv.net/gimg/pprune....a73774703.jpeg

malabo 27th Mar 2021 23:27

The AAIU has already determined it was not the crew’s fault. The pilot was licensed and qualified by the authority and followed the published SOP to the letter, nobody to blame.

But even less seriously...looks like he wanted to taxi to the left, aircraft resisted so he tried a little harder, then remembered the nosewheel lock and when it released the aircraft spun left with full left pedal applied. This threw the pilot to the right still hanging on to the cyclic and collective. So on top of the yaw the pilot has now got the collective coming up and full right cyclic. The aircraft is truly embarrassed at the overreaction by the pilot to the initial slow left turn and rolls over in shame.

fodder for weeks to come on pprune

gulliBell 27th Mar 2021 23:52

What surprises me is pilots are still finding new ways to needlessly prang helicopters.

ericferret 27th Mar 2021 23:54


Originally Posted by gulliBell (Post 11017659)
What surprises me is pilots are still finding new ways to needlessly prang helicopters.


and new ways to kill the ground crew.

Sir Korsky 28th Mar 2021 00:50

they should have just put a damper in and had done with it

jimf671 28th Mar 2021 00:56


Originally Posted by ericferret (Post 11017660)
and new ways to kill the ground crew.

The guy legging it towards the corner of the hangar caught on pretty quick. Best decision-maker portrayed here!

malabo 28th Mar 2021 00:59

Yep, watch his body language as the 169 inches forward - he knows bad things gonna happen.
Puma guys can sympathize.

ShyTorque 28th Mar 2021 01:08


Originally Posted by gulliBell (Post 11017659)
What surprises me is pilots are still finding new ways to needlessly prang helicopters.

But this looks like an old way!

However, I do wonder if this has any similarity to the tragic accident at Leicester football ground....it looked like yaw control was completely lost.

helicrazi 28th Mar 2021 05:11

Looks more like a load of pedal then a sudden release of nosewheel lock.

I wonder of the paws were a hindrance when it started to go?

nut 28th Mar 2021 05:33

Video of rollover
 
https://bithome.ch/wp-content/upload...169Bolzano.mp4




m32k 28th Mar 2021 06:29

Same happened a few years ago in UAE: different heli but same scenario, same cause, same ending.
It has been covered up (obviously) but the wreckage is still visible at the airport.

ShyTorque 28th Mar 2021 09:50


Originally Posted by helicrazi (Post 11017735)
Looks more like a load of pedal then a sudden release of nosewheel lock.

I wonder of the paws were a hindrance when it started to go?

Yes, that’s obviously how it started but why no opposite pedal once it began yawing?

Fareastdriver 28th Mar 2021 10:05

The main gearbox breaking up doesn't fill me with much confidence. I've seen a couple of roll overs, have been in one, but the gearboxes have kept their integrity.

collectivethrust 28th Mar 2021 10:23

The MGB looks intact as the shaft and beanie are still in place. The MR Head has come apart, little surprise. Fuselage retains shape and doors remain in place. Cabin door still slides open.

Koalatiger 28th Mar 2021 12:01


Originally Posted by helicrazi (Post 11017735)
Looks more like a load of pedal then a sudden release of nosewheel lock.

I wonder of the paws were a hindrance when it started to go?

Sure looks like that, you can see when the nosewheel lock being released that the nosewheel swings 90degrees immediately indicating alot of left pedal...

212man 28th Mar 2021 12:36


Originally Posted by Fareastdriver (Post 11017859)
The main gearbox breaking up doesn't fill me with much confidence. I've seen a couple of roll overs, have been in one, but the gearboxes have kept their integrity.

I’m watching on my phone, but don’t see the MGB breaking up?

[email protected] 28th Mar 2021 13:22

Can't see MRGB break-up either.

Difficult to see why he didn't take any corrective action.

homonculus 28th Mar 2021 13:36


Difficult to see why he didn't take any corrective action.

The AAIU has already determined it was not the crew’s fault. The pilot was licensed and qualified by the authority and followed the published SOP to the letter, nobody to blame.
Simple answer

helicrazi 28th Mar 2021 13:57


Originally Posted by homonculus (Post 11017990)
Simple answer

I think you'll find that entire post is sarcasm... :ugh:

DOUBLE BOGEY 28th Mar 2021 16:10

It looks like a hardcover to the anti torque side (negative power pedal). Absolutely no response on the pedals. OR full left pedal tryin to defeat the nose wheel lock that either fails or is removed. Just can’t see why the opposite pedal is not put in. The puma goes instantly when the nose wheel over centres so cabs will spin easily once the nose wheels are in the 90 degree position. Just can’t get why opposite pedal seems absent.

krypton_john 28th Mar 2021 20:13


Originally Posted by ShyTorque (Post 11017852)
Yes, that’s obviously how it started but why no opposite pedal once it began yawing?

Is it yawing because of MR torque or because of TR torque?

[email protected] 28th Mar 2021 21:58


Is it yawing because of MR torque or because of TR torque?
it seems because he put far too much pedal input - he could have lifted to the hover and not crashed the aircraft

ShyTorque 28th Mar 2021 23:30

The blades on the 169 rotate anti-clockwise as seen from above. The tail rotor is on the right of the tail, so it’s a “puller”, rather than a pusher.

It remains to be published whether or not the pilot actually retained control of tail rotor pitch.

If the control linkage failed, as in the Leicester AW169 accident, he may have initiated a yaw only for t/r pitch to run away to full travel. In this case it looks like an uncontrolled amount of positive (power) pedal pitch was involved, rather than the negative pitch that caused the Leicester aircraft to go out of control.

[It used to be part of the RAF Puma conversion course how to learn how “drive” the aircraft forwards out of the situation where the nose wheel had accidentally become fully cocked off to the side. The first part of that recovery was to centralise the yaw pedals to avoid the aircraft rotating uncontrollably, and use the independent main wheel brakes to help stabilise and steer, rather than big bootfulls of pedal. It was important to get this right, due to the high mounted tail rotor the Puma will roll very rapidly and markedly if too much pedal is used on the ground].

Nescafe 29th Mar 2021 01:16

It appears that as the aircraft moves forwards pedal is applied to turn left, so much so that the aircraft actually leans over to the right. The pilot stops forward motion (at 26 seconds), releases the pin and its all over.

jb68321 29th Mar 2021 02:28

So is this just a case of Italian authorities trying to sweep pilot error under the rug? Or did I misunderstand you? Certainly seems like a few pilot errors from my perspective, but I'm not so experienced with AWs. I've heard some stories about the company culture and Italian authorities before though...


The AAIU has already determined it was not the crew’s fault. The pilot was licensed and qualified by the authority and followed the published SOP to the letter, nobody to blame.

SpindleBob 29th Mar 2021 07:40

As said above - That comment about the Italian authorities was just sarcasm - A joke!!

Fair play to the second ground crew - The one furthest from the camera - He was actually running towards the fire extinguisher and still ducking for cover while the aircraft was rolling and showering the ramp in debris. I don't know whether to put him forward for a medal or clip him round the ear!!

Flying Bull 29th Mar 2021 12:14

Hi,
there is a video online on Facebook, where the scenario is replayed in a simulator.
The sim crashes even faster
-R&c[0]=AT2Ip82GROK-OC0FGukaE3KkBck4XtOJ8CVtD75qWZu6FYDWQ4MAKaxkXpxaaZfAPhF5st4a ytG6KQocI7vB23lT0jK1IRlopThWYJCgn7DGmNJ7Ca2W0IG9otSZ68THO5Q0 vpvowzoSGdkwJee0b2Uw-Ba0uyIwd9RxR-GVRrcj3lqa6UMKielU8Lg]Facebook-Link to video

hargreaves99 29th Mar 2021 13:06

it looks like they were trying to taxi and turn left (ie left pedal in) and the nosewheel lock was engaged, when the noseweel lock was taken out, the wheel "flicks" to the left quickly (you can see this in video if you look closely), as a lot of left pedal was already applied the aircraft started to rotate left quite rapidly.

like with any pedal/rotation scenario, once an aircraft has completed one or two 360s the pilot will be so disorientated/surprised/frozen in terror... in most cases it's "game over"

ApolloHeli 29th Mar 2021 13:17

Here's a link to the Facebook video referenced earlier (same scenario replicated in a simulator)

https://imgur.com/a/1DA60zZ

I copied and re-uploaded the video as it was difficult to locate in its original form on Facebook.

gulliBell 29th Mar 2021 19:12

And what does the flashing light on the CWP signify the moment things start to go pear shaped?

Droopy 29th Mar 2021 19:18

That's the nosewheel going through the process of unlocking.

ZAGORFLY 29th Mar 2021 19:33

Incomplete analysis
 
I believe the explanation is incomplete because the pilots would have obviously apply correction rudder right to stop the uncommanded left rotation that let me think that is a hydraulic jam here in place.

[QU=malabo;11017649]The AAIU has already determined it was not the crew’s fault. The pilot was licensed and qualified by the authority and followed the published SOP to the letter, nobody to blame.

But even less seriously...looks like he wanted to taxi to the left, aircraft resisted so he tried a little harder, then remembered the nosewheel lock and when it released the aircraft spun left with full left pedal applied. This threw the pilot to the right still hanging on to the cyclic and collective. So on top of the yaw the pilot has now got the collective coming up and full right cyclic. The aircraft is truly embarrassed at the overreaction by the pilot to the initial slow left turn and rolls over in shame.

fodder for weeks to come on pprune[/QUOTE]

etudiant 29th Mar 2021 20:14

Can only say 'Oh wow!'.
An aircraft in perfect shape, destroyed in seconds because of the nose wheel not being unlocked in time?
If this is representative of the sensitivity of helicopter flying, it explains a lot.
The question that remains is why do very wealthy people accept such low safety standards.

hargreaves99 29th Mar 2021 20:21

unlikely, the fast left yaw would have taken them by surprise and they would have quickly got disorientated


>I believe the explanation is incomplete because the pilots would have obviously apply correction rudder right to stop the uncommanded left rotation that let me think that is a hydraulic jam here in place.

helicrazi 29th Mar 2021 20:26


Originally Posted by etudiant (Post 11018792)
Can only say 'Oh wow!'.
An aircraft in perfect shape, destroyed in seconds because of the nose wheel not being unlocked in time?
If this is representative of the sensitivity of helicopter flying, it explains a lot.
The question that remains is why do very wealthy people accept such low safety standards.

I missed what this has to do with wealthy people?

atakacs 29th Mar 2021 20:28


The question that remains is why do very wealthy people accept such low safety standards.
In this specific case I thnk those guys are supposed to go after the wealthy people (Italian fiscal police )

SpindleBob 29th Mar 2021 20:32

OK, so if we accept that this may well be the cause. Certainly taking out the nose wheel lock with full left pedal, can go very wrong very quickly.

What is the learning? Pilot training? Lift into the hover like ground resonance - Last thing you want to do when you feel like you might have lost tail rotor control, is to get in the air! Perhaps with the violent rotation, your feet might get swept of the pedals?

If this has happened twice by the sound of it, would a software interlock be worthwhile? One that doesn't allow the nose wheel to be unlocked unless the pedals are set at no more than +/- 30% power for example?

helicrazi 29th Mar 2021 20:32


Originally Posted by ZAGORFLY (Post 11018773)
I believe the explanation is incomplete because the pilots would have obviously apply correction rudder right to stop the uncommanded left rotation that let me think that is a hydraulic jam here in place.

This wasnt uncommanded, it was commanded, and as soon as they realised they had forgotten the nosewheel lock and unlocked it (the amber flashing lights in the sim) they got the yaw they commanded.

helicrazi 29th Mar 2021 20:36


Originally Posted by SpindleBob (Post 11018802)
OK, so if we accept that this may well be the cause. Certainly taking out the nose wheel lock with full left pedal, can go very wrong very quickly.

What is the learning? Pilot training? Lift into the hover like ground resonance - Last thing you want to o when you feel like you might have lost tail rotor control, is to get in the air!

If this has happened twice by the sound of it, would a software interlock be worthwhile? One that doesn't allow the nose wheel to be unlocked unless the pedals are set at no more than +/- 30% power for example?

Only 1 aw169 that we know of. It happens on most types, especially puma as detailed earlier.

Pilots are trained, sop's are written, people dont follow them, the cause of many accidents.

etudiant 29th Mar 2021 20:37


Originally Posted by helicrazi (Post 11018797)
I missed what this has to do with wealthy people?

Think recent accidents in Alaska, earlier in France, the Caribbean and before that a UK stadium, all billionaires, wiped out by their helicopters


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