PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Rotorheads (https://www.pprune.org/rotorheads-23/)
-   -   Norways first AW101 on its side (https://www.pprune.org/rotorheads/602325-norways-first-aw101-its-side.html)

Winnie 24th November 2017 21:38


Originally Posted by Aesir (Post 9968237)
Probably a translation from Aftenbladet newspaper.



Actually I believe a "Flygere" could also be construed as Airman or Aircrew. It is common in Norway for mechanics to do ground run on helicopters since pilots are rather expensive to call out there for startups. Ground resonance is a possibility then.

Any native Norwegian speaker care to comment?

Native Norgie living in Canada...

Flyger is the term for Pilot, can also be Flyver. The paragraph states "Two experienced Pilots"

There also were 4 people outside the aircraft at the time of the accident.

The military would not let an Engineer (flight mechanic) do the runs. Minimum 1 winged pilot in the captain's seat.

H.

M609 24th November 2017 21:57

https://gfx.nrk.no/P9UImTSxaP5xwGMS0...BeAThM6jMMEyJQ

BluSdUp 24th November 2017 22:03

Aesir
 
I speak and read both norwegian languishes, that is not the problem.
The way it is written it says it was two pilots.
For a military spokesman it is worded a bit strange: "The persons on board belonged to the personnel doing testing on the helicopter."
" Two experienced pilots was at the controls when it happened."

Military officers always refer to other personnel as soldiers ( Privats) or Officers.
Anyway.
We shall know soon enough .
Lets hope it is not a mechanical problem. We need the new capable Aw101!

gulliBell 25th November 2017 11:48


Originally Posted by FNTC (Post 9967956)
"The helicopter flipped over while the engine and rotor were running, and it was performing what we call ground driving. The rotor blades have touched the ground during the incident, says Stordal"

My hunch is "ground driving" = ground taxiing, they were light on fuel, whipped it around the corner a bit too fast and she rolled over...hard to believe it would roll over on a stationary ground run.

AAKEE 25th November 2017 13:58


Originally Posted by gulliBell (Post 9968732)
My hunch is "ground driving" = ground taxiing, they were light on fuel, whipped it around the corner a bit too fast and she rolled over...hard to believe it would roll over on a stationary ground run.

Nope.

”Bakkekjøring” should be read as Ground run.
I dont know anything about this particular case, but some helos tail rotor thrust is capable of flipping it over, perhaps in conjunction with wind.

M609 25th November 2017 15:10

https://www.aftenbladet.no/lokalt/i/...a#&gid=1&pid=1

Some more close ups

heliduck 25th November 2017 16:02

Nobody wants to be the first person to put a scratch in any new toys.....Now that’s out of way.

[email protected] 25th November 2017 20:05

Dynamic rollover or Ground Resonance.

TR thrust is pushing to the right so a crosswind from the left would make it worse - lack of into wind cyclic and a light weight (higher vertical C of G) all combined could easily create the right conditions for dynamic rollover.

malabo 25th November 2017 23:58

The Nigerian one was laying on its left side, this one is on the right - less chance they have anything in common. Been a few 92's that got inadvertently airborne on startup from the collective creeping up (like the elastomerics do to a 412). The 101 is a pretty well-respected SAR machine here in Canada, the only losses were from low-time pilots messing up autopilot use during night/low level.

llamaman 26th November 2017 08:28

You'd have to be going some to put a 101 on it's side during a ground run. It's a pretty stable machine in that environment so would either have to be gross mishandling or mechanical failure.

cattletruck 26th November 2017 09:34

Conditions do look a bit slippy, perhaps that was a contributing factor.

BluSdUp 26th November 2017 11:36

Ilamaman
 
I understand You fly the AW101. What kind of mechanical failure would lead to this result?
Secondly, what error would a crew do to end up with such a catastrophic result?
Is the AW101 much different handling from the SeaKing the crew came from?
How good is the simulator the crew was trained in in Your opinion?
It was daylight and some gusty winds at the day,but nothing dramatic.
Looking forward to an insiders observations.

Any other AW101 drivers out there who care to comment on the handling peculiaritys and performance versus the SeaKing?

davigal 28th November 2017 15:20


Originally Posted by BluSdUp (Post 9969558)
I understand You fly the AW101. What kind of mechanical failure would lead to this result?
Secondly, what error would a crew do to end up with such a catastrophic result?
Is the AW101 much different handling from the SeaKing the crew came from?
How good is the simulator the crew was trained in in Your opinion?
It was daylight and some gusty winds at the day,but nothing dramatic.
Looking forward to an insiders observations.

Any other AW101 drivers out there who care to comment on the handling peculiaritys and performance versus the SeaKing?

Hi guys, I’m a formal EH101 driver, 1500 hrs on it, the problem this machine has on the ground is that it has to be taxied without using the tail rotor thrust. It uses exclusively the main rotor thrust. The front wheel has a mechanic hydraulic steering and if you use the tail rotor you may encounter the situation the gentlemen faced. Other cause is the taxing with autopilot on. Unlike the other helicopters, the Merlin has to be taxied, to avoid any unwanted input on the TR, with the feet on the ground and apply breaks with the feet only on request. Is stated on the manual that taxi with the AP on is highly dangerous due to the heading hold function of the TR embedded in the system. Taxing with the autopilot on may induce rollover due to the increased thrust of the TR during any turn to maintain heading with the AP on (trim release microswitches are on the pedals).
Third and last option maybe that on the struts, there are some selectors to harden the struts when the helicopter is parked on a moving deck or in windy conditions, failure to release those may incur in a unbalanced taxi and possible ground resonance/dynamic rollover, I.E. one released one not or both unreleased.
Hope this helps understand my view but I’m not a test pilot or investigator.
Bye

JohnDixson 28th November 2017 16:30

Is there anyone viewing who can amplify on the underlying reasons behind this design concept?

tottigol 28th November 2017 16:36

Any possible relation?
Alert 5 » JMSDF CH-101 crashes - Military Aviation News

fadecdegraded 28th November 2017 17:03


Originally Posted by davigal (Post 9971920)
Hi guys, I’m a formal EH101 driver, 1500 hrs on it, the problem this machine has on the ground is that it has to be taxied without using the tail rotor thrust. It uses exclusively the main rotor thrust. The front wheel has a mechanic hydraulic steering and if you use the tail rotor you may encounter the situation the gentlemen faced. Other cause is the taxing with autopilot on. Unlike the other helicopters, the Merlin has to be taxied, to avoid any unwanted input on the TR, with the feet on the ground and apply breaks with the feet only on request. Is stated on the manual that taxi with the AP on is highly dangerous due to the heading hold function of the TR embedded in the system. Taxing with the autopilot on may induce rollover due to the increased thrust of the TR during any turn to maintain heading with the AP on (trim release microswitches are on the pedals).
Third and last option maybe that on the struts, there are some selectors to harden the struts when the helicopter is parked on a moving deck or in windy conditions, failure to release those may incur in a unbalanced taxi and possible ground resonance/dynamic rollover, I.E. one released one not or both unreleased.
Hope this helps understand my view but I’m not a test pilot or investigator.
Bye

That’s quite a list and all makes sense.
One would think that there’s a pre taxi checklist with so many scenarios that could catch you out

davigal 28th November 2017 17:09


Originally Posted by JohnDixson (Post 9971993)
Is there anyone viewing who can amplify on the underlying reasons behind this design concept?

The design on the nose wheel steering is self explanatory, a helicopter nearly 17 tons is better taxied of course with a nose wheel steering system, like on medium size airplanes on rather that stressing the fuselage with a tail rotor steering system. The strut design is as well justified because the helicopter design is originally for maritime/offshore use and whoever has been in the offshore/navy world knows how uncomfortable is having a helicopter parked on a deck that is rolling on a period that is in counter face to the period of the rolling deck on a sea state due to the struts that are working hard to keep the helicopter parallel to the ground as per the design of any dampener. Going further on the possible causes, it has been mentioned PIO (pilot induced oscillation) it happened to me either in flight with an underslung load of 2,5 tons and during landing on a deck. Someone has named it as ground resonance but is clearly PIO because increases with the time and even if you get airborne and remove the pivoting point (ground resonance cause) the aircraft still shakes increasingly. It can result in a loss of control and catastrophic consequences. The pilot should release momentarily the controls and the aircraft instantaneously stops shaking..... good luck with that!!! 😁

pants on fire... 28th November 2017 18:22

Reminds me of...
 
Customer: 'Ello, I wish to register a complaint.

(The owner does not respond.)

C: 'Ello, Miss?

Owner: What do you mean "miss"?

C: I'm sorry, I have a cold. I wish to make a complaint!

O: We're closin' for lunch.

C: Never mind that, my lad. I wish to complain about this chopper what I purchased not half an hour ago from this very boutique.

O: Oh yes, the, uh, the Norwegian Blue...What's,uh...What's wrong with it?

C: I'll tell you what's wrong with it, my lad. 'E's dead, that's what's wrong with it!

O: No, no, 'e's uh,...he's resting.

C: Look, matey, I know a dead chopper when I see one, and I'm looking at one right now.

O: No no he's not dead, he's, he's restin'! Remarkable bird, the Norwegian Blue, idn'it, ay? Beautiful plumage!

C: The plumage don't enter into it. It's stone dead.

O: Nononono, no, no! 'E's resting!

C: All right then, if he's restin', I'll wake him up!

(shouting at the cage)

'Ello, Mister Polly Parrot! I've got a lovely fresh cuttle fish for you if you show...(owner hits the cage)

O: There, he moved!

C: No, he didn't, that was you hitting the cage!

O: I never!!

C: Yes, you did!

O: I never, never did anything...

C: (yelling and hitting the cage repeatedly) 'ELLO POLLY!!!!!

Testing! Testing! Testing! Testing! This is your nine o'clock alarm call!

(Takes parrot out of the cage and thumps its head on the counter. Throws it up in the air and watches it plummet to the floor.)

C: Now that's what I call a dead parrot.

O: No, no.....No, 'e's stunned!

C: STUNNED?!?

O: Yeah! You stunned him, just as he was wakin' up! Norwegian Blues stun easily, major.

C: Um...now look...now look, mate, I've definitely 'ad enough of this. That parrot is definitely deceased, and when I purchased it not 'alf an hour ago, you assured me that its total lack of movement was due to it bein' tired and shagged out following a prolonged squawk.

O: Well, he's...he's, ah...probably pining for the fjords.

C: PININ' for the FJORDS?!?!?!? What kind of talk is that?, look, why did he fall flat on his back the moment I got 'im home?

O: The Norwegian Blue prefers kippin' on it's back! Remarkable bird, id'nit, squire? Lovely plumage!

C: Look, I took the liberty of examining that parrot when I got it home, and I discovered the only reason that it had been sitting on its perch in the first place was that it had been NAILED there.

(pause)

O: Well, o'course it was nailed there! If I hadn't nailed that bird down, it would have nuzzled up to those bars, bent 'em apart with its beak, and VOOM! Feeweeweewee!

C: "VOOM"?!? Mate, this bird wouldn't "voom" if you put four million volts through it! 'E's bleedin' demised!

O: No no! 'E's pining!

C: 'E's not pinin'! 'E's passed on! This chopper is no more! He has ceased to be! 'E's expired and gone to meet 'is maker!

'E's a stiff! Bereft of life, 'e rests in peace! If you hadn't nailed 'im to the perch 'e'd be pushing up the daisies!
'Is metabolic processes are now 'istory! 'E's off the twig!
'E's kicked the bucket, 'e's shuffled off 'is mortal coil, run down the curtain and joined the bleedin' choir invisibile!!

THIS IS AN EX-CHOPPER!!

roybert 28th November 2017 18:35


Originally Posted by heliduck (Post 9968910)
Nobody wants to be the first person to put a scratch in any new toys.....Now that’s out of way.

I agree Heliduck but most individual I know just hit a hidden corner with a ballpeen hammer to put the dent it to get it over with. This is a little extreme

davigal 28th November 2017 21:12


Originally Posted by fadecdegraded (Post 9972024)
That’s quite a list and all makes sense.
One would think that there’s a pre taxi checklist with so many scenarios that could catch you out

I see your point and I agree with that but my original reply was for a post asking what are the possible muscle memories for a driver which is an ex sea king qualified. If you were an ex sea king pilot you probably remember that the sea king is taxied with the thrust of the tail rotor using a tail wheel that’s free of moving. It’s s total different concept and it may induce fresh qualified pilots in error. I had to force myself the very first flights (100 has or so) not to step on the pedals. As I wrote below the causes could be also PIO (pilot induced oscillation).


All times are GMT. The time now is 22:26.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.