Edson AB crash, VRS?
 

Edson AB helicopter crash

Yesterday, A350 B2. Downwind, looking at the subsequent smoke. VRS or loss of power?

Strange. Would not bet on VRS. Too much forward speed and no waggling of tail. Loss of power? Might be, but still strange. I'll wait for the report. Could be an interesting read.
But it looked like he landed with quite a bit of tailwind. Why would he do that?

Maybe this is that thing where they simply waited too long to apply the brakes?

Just once I would like to see a brand new first ever way to crash a helicopter.

Open airfield with at least one wind sock somewhere....and the Ace lands downwind with a near gale blowing.....now what could possibly go wrong in a situation like that?

The good news is either the crashworthy fuel system worked....or there was not enough fuel in the system to feed a fire.

I am not sure, but in the beginning of the video there is something that looks like a windsock. Very blurry, but it is straight out in the direction of flight. Could have been a clue.

Looking at the video it appears to me as a “Perfect” VRS entry. The tailwind would make the machine look “faster” due to the higher ground speed. His airspeed would have been much lower. You can see the sudden increase in rate and angle of descent.

Just my opinion. The report will hopefully provide Truth.
Glad the pilot is only shaken but OK.

Agreed, the sudden increase in ROD is a fair indicator of VRS on a downwind approach.

Don’t they teach people how to get from downwind to into wind whilst maintaining ETL any more?

Think he is moving forward too quickly and the ROD doesnt look that high for VRS, Think he lost translational lift, realised too late was going down too quickly and overpitched it.

Yupp, I go with that, too. Exactly my thinking.

His forward speed pretty much match the windspeed. His ROD is increasing, but lucky for him he didn’t have much height to start with. If he had had a bit more height, the damn thing would pancake even harder, as the VRS would develop properly.

What this guy was thinking is hard to comprehend…

The video in the OP's link won't open for me, so here it is if others are having similar trouble.

Sooooo, settling with power, then?

To get VRS in a 350 you have to catch up your downwash, that is around 800 / 900 ft a minute ROD ( depending on how heavy the helicopter is , the heavier the machine the more downwash and therefore less likely to catch up the downwash ). I demo incipient VRS in a Hu 300 for ppl's, ROD 500 ft a minute lee than 20 kts and 18" MAP the book says one is in VRS, I will demo pull the power back in, the 300 stops descending and climbs back up, so no VRS because we have not caught up our downwash. To me the 350 as our cousins from across the pond say is settling with power or as we would call overpitching. Simply put the pilot has forgotten his energy mangement. The airframe has built up too much energy by descending too fast, he has come off translational lift ( downwind ) he has then forgotten that by pulling power the nose pitches up robbing him of even more translational lift ( what little he has ) now asks engine for more energy, puts in a boot load of right pedal, ( (bet the power alarm was gong off if it was a B3)even more energy is robbed from the main rotor and down she goes as he overpitches everything . Might be wrong but the ROD for me is not high enough for VRS ! Stand to be corrected here

The classic way to get VRS is on a downwind approach - as he is.

Then let yourself get steep - as he does.

Then start to try to recover with power - as he does.

Then try to reduce speed with a flare that won’t have any effect due to being downwind - as he does.

Then experience what some long-line pilots describe as falling into a hole - as he does.

And finally crash because you don’t have enough height for recovery - as he does.

You need a RoD between 0.5 and 0.75 approx of your down wash speed to encounter VRS with a forward airspeed of less than about 15 Kts - the lighter the aircraft the lower the RoD required as the downwash speed is lower.

He may not have got into fully developed VRS but I see no indication of over pitching or settling with power.

I remain with VRS as the cause.

Well, the result is the same. Anyway, I am still on Hughes500's side. VRS needs time to set up. You have to pump energy in these vortices. Even if it may feel like it, VRS does not occur in the blink of an eye. It starts before the pilot even feels something. And in this case, I would expect that the tailwind, which is conventional airspeed but from the wrong end, would disturb the formation of the vortices.
And as we have all stated numerous times in the past, VRS-accidents are rare, very rare. Much rarer that some want to make us believe. Overpitching is much more common.
He came in hot, descending, had the collective down, flared and was slow on the power management when the flare did not bring the results he was anticipating. And it was a B2. Other blades and engine than the B3 or B3e. Though, if, as H500 suggest, a B3 would already yell at the stick jock, the B2 is worse.

VRS?
Overpitching?
Just a dumbass?

Taking all bets :cool:

VRS needs 3 conditions to be met - high RoD (0.5 to 0.75) of your downwash speed, low IAS and then power applied.

In the video he clearly has 2 out of the three thanks to a steep downwind approach but doesn’t hit VRS until he brings in the power, builds the tip vortices and begins to stall the roots.

He doesn’t have enough height to recover and his only option is to try and power out of it which just makes it worse.

He may over pitch it right at the end in panic mode but VRS did the damage there.

Definitely dumbass I reckon Robbiee :ok:

Settling with power usually comes as a result of trying to establish an OGE hover without the power margin to do so.

Crab, so what is 0.75 of the downwash of a B2 then ? having loads of time in a B3 with a line lifting I would suggest that its downwash speed is pretty close to 1000 ft plus a minute. In over a 1000 hours of lifting on a longline never experienced the " hole" or near vortex ring. What have had is getting pretty close to dumping the load a I have let the ac and load build up too much energy on a steep approach and got my energy management all wrong, ended up luckily getting the load on the ground as the FLI hit 10 banana's and a bong in the headset. No damage done aprart from a quick change of underwear and that was just the ground crew !!!!!!! Just as well I was wearing brown trousers