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View Full Version : Can someone explain what went wrong here please?


Razor61
31st Oct 2010, 10:05
YouTube - SH-60 Near Crash (http://www.youtube.com/watch?v=BEuFLNDAltw)

SH-60 apparently with SEAL's onboard comes in and nearly prangs it big time.
Was it due to the fact they may have had more bank than they should have and lost all lift or was it another factor?

Amazing recovery anyway and the rotors must have been inches from touching the ground atleast twice.

Flap62
31st Oct 2010, 10:25
Not being a helo man even I can see what caused that - the cameras were there!

Pontius Navigator
31st Oct 2010, 10:31
Looks as if the ground rose more suddenly than he expected?

BOAC
31st Oct 2010, 10:33
Razor - the technical term is 'cock-up'.

Barry Bernoulli
31st Oct 2010, 10:38
Could it have been the same thing that caused this?

YouTube - Black Hawk Crash (http://www.youtube.com/watch?v=6i3tbLuePb4)

BossEyed
31st Oct 2010, 18:47
Not the same incident, SP.

airborne_artist
1st Nov 2010, 10:39
The handling pilot was on a promise that night, and his brain was not in the cockpit.

No other sensible explanation.

ShyTorque
1st Nov 2010, 11:07
Insufficient application of power to arrest an increasing rate of descent caused by a steeply banked turn at high all up weight appears to be the only logical answer.

Can't understand why it occurred as the aircraft appeared to have sufficient power immediately after the event.

charliegolf
1st Nov 2010, 11:13
Can't understand why it occurred as the aircraft appeared to have sufficient power immediately after the event.

Perhaps the whole situation had the pilot's undivided attention by then!:ok:

CG

Not everyone is blessed with your God-given skill and aplomb Shy.
(Cheque to the usual?)

Wizzard
1st Nov 2010, 12:13
What the two incidents have in common - allegedly - is that they were carrying Special Forces and as one who has worked with "them" before I can vouch how easy it is to get carried away with their enthusiasm or as they would put it "mission focus"

They were so focused one dark night in Germany that they jettisoned my doors instead of opening them:rolleyes:

That might be the background to the OP but the real reason of course is:

the cameras were there!

chinook240
1st Nov 2010, 18:30
Insufficient application of power to arrest an increasing rate of descent caused by a steeply banked turn at high all up weight appears to be the only logical answer.

Have to agree it looks that way, possibly insufficient power to arrest an increasing ROD, he's got a large coning angle just as he strikes the ground suggesting he's pulling collective like a b#%&*d.

Sun Who
1st Nov 2010, 18:46
My guess:
Aggressive approach looking for a late flare to zero-zero.
Visual approach not taking info from rad or bar-alt and confused by low contrast, low feature surface which deceived the pilot into thinking he was higher than he was. Exacerbated by the approach being over lower ground than the LZ.

Sun.

heliboy999
3rd Nov 2010, 15:54
Looks like from the direction the dust blows after the near miss, the wind was blowing away from the camera and the helicopter looked like he was turning into wind but instead turns crosswind with what looks like a "slipping" turn, It looks like a case of Incipient Vortex ring or settling with power which would semi dissipate as the helicopter closed with the ground but the rate of decent has grown too much for the power required.
The Coning angles on the rotor show that there was a huge amount of power but it would have been interesting to see what engine/transmission limits had be well and truly busted by the recovery.
My interpretaion but happy to learn fom any other ideas.

:8

ShyTorque
3rd Nov 2010, 16:50
I don't agree that it was VR related.

Also, if you look carefully and stop the video incrementally, the coning angle initially seems quite low but increases markedly just as the aircraft has first "touched" down.

I reckon he was just too late on the collective.

Navy pilots.... :rolleyes:

;)

Buster Hyman
3rd Nov 2010, 22:01
Give him his due...he didn't "punch out"...

AH7
4th Nov 2010, 21:56
The reason for this near huge crash is a simple POF issue. When using lets say 60 deg angle of bank we now have total reaction tilted over in this case to the right. Due to this total reaction we have a total rotor thrust horizontal and a reduced total rotor thrust vertical, which is key. To maintain height he would need to increase that TRT vertical by about twice as much. 60 deg AOB has the effect of increasing the AUM by 100%. This bloke clearly did not know this and if he was heavy or high he would not have enough power to maintain height. Sorry if this bores you but that is the reason.....!!!!!:O

peeush
6th Nov 2010, 15:23
I think he just lost sight of his priority too close to mother earth- may be he was looking inside OR somewhere else when the descent set in. He was too close to the ground for such a diversion (if there was any). Anyway, he has lived to be more careful next time and given us experience without getting into a tight spot!!

MightyGem
6th Nov 2010, 19:32
I think that it's more likely he was just trying too hard to put on a show for the audience.