Dynamic Rollover video in Rotorway
 

Found this one today.

Apologies if already posted.




HB999

from an armchair point of view, perhaps the frequencies were not matched......?

http://i10.photobucket.com/albums/a1...ntrol-unit.jpg

hugs

xxx

f

It amazes me that this continues to happen. Surely it's absolutely basic, fundamental training to deal with onset of DR?

It would probably amaze you when it happened to you also.

I know someone who built one of these and was cautioned that he should take some instruction in it before flying it.

He only had about 10,000 hours in helicopters at the time. He said "the guy was right" I probably would have tipped it over.

Your neck of the woods too KJ.

What I want to know is what was going on with the engine? It sounds like the RPM's were decreasing the entire time. I'm not trying to monday-morning quarterback the situation (but maybe I'm doing it anyway?) but if I'm flying something and the RPM's keep dropping like it sounded like they were, I'd have probably set it down a tad quicker.

Then again, maybe that wasn't the best spot for a test flight, assuming it was newly built. If it wasn't, and anyone knows the details, I will eat my words gladly. Heck, I'm just glad the fellow ONLY lost his ship in this one. I know what it feels like to be in denial of the situation at hand.

RVDT, I have heard it said many times about the RW, that transition instruction is more important in this type than just about any other, particularly with regard to DRO.

The pilot in the video attempted to correct out the roll-over, instead of dumping the collective which probably would have saved the ship.

Either pure lack of type training or poor skill.

[Edit] - I just watched it again with the sound on - sounded like the rpm started audibly dropping well before he got into trouble.

Seems like lack of ability in overall charge of that RW, the correction almost works buy sadly we all see the result!

Peter R-B

How refreshing...as yet nobody's slagged the type !

"poor skill"

"lack of ability in overall charge of that RW"

'Nuff said.......

Dynamic rollover can be achieved in any helicopter and the correcting action is pretty much the same in any helicopter. Its always a shame to see a machine damaged whatever the type but its a nice video to demonstrate the situation and how easy it can occur and also how quickly.

Sad to watch, given the reported experience of the driver. But verrrrrry eentereshting!

The Rotorway's rotor(way!) turns the same direction as a Squirrel, opposite that of a Bell. So the nose will tend to want to turn to the left, requiring a bootful of right-pedal to keep it straight. In watching the video, you can hear the main rotor rpm clearly decreasing - and with it, the T/R rpm. The pilot appears to be focusing on...something else...and *probably* doesn't realize that he's just about out of right pedal.* The right skid touches and then the yaw rate begins. From our vantage point, it's easy to see what's coming. And it does.

Classic case of DR.

Man, I can so put myself in his shoes. "I know how to hover a friggin' helicopter, I can hover this thing."I can hear myself saying it. And Fate laughs and says, "Oh yeah? I'm gonna re-teach you something you may have forgotten about low tail rotor authority and decreasing t/r rpm, and how easy helicopters are to crash."

Ouch.




*Or, maybe he's just not aggressive enough with the right pedal. Just before it rolls over, you can see a little twitch of the nose to the right. So it mad me wonder: Did he have some pedal available that he wasn't using? In any case, he seems very rough on the cyclic. Or was it just a very gusty day?

FH1100

Just to answer the gusty day question and nothing more.

METAR EGSS 201350Z 36006KT 300V050 CAVOK 16/08 Q1027
METAR EGSS 201420Z 01005KT 320V080 CAVOK 16/07 Q1027
METAR EGSS 201450Z 34004KT 300V030 CAVOK 16/07 Q1027
METAR EGSS 201520Z 02005KT 310V050 9999 FEW040 17/07 Q1026

From Stansted a few miles away.

Looks to me like the pilot lost RRPM because was not used to flying without a governor perhaps?
I speculate that pilot lifts into the hover, rpm starts to decay, so raises the lever, which decays rrpm even more and so raises the lever even more and so on.
Classic over pitching due to lack of manual throttle management. This easily occurs when learning, say in an R22 with the governor on, then flying another type with no governor or corellator.
Corrective action should have been to twist in more throttle and lower lever to recover RRPM.

Have any of you read the report?

All the pilot's hours were on type so I'm guessing he was used to lack of governor. I'd also hint that the pilot didn't need any transition training.

Wind also quoted as less than 5 kts.

Cheers

Whirls

Can you learn on a rotorway in the US?

krypton_johndump (dump)
Transitive verb
To throw down or out roughly; empty out or unload as in a heap or mass

By 'dumping the collective lever'...do you not mean, 'lower the collective smoothly'?

Surely 'dumping' the lever would very possibly cause the aircraft to bounce on the other skid and roll in the other direction. (Not forgetting the potential risk of ground resonance)

Sid, your wording is much better!

Let uss know when you manage to get ground-ressonance with a semi-rigid rotorsystem....

Surely dumping the collective will have a higher success rate? As I recall, the 'tip over angle' is smaller for a loaded disc (because the lift acts through a point higher than the CofG), and therefore means that it will never tip over in the other direction with the collective lowered. Especially so, when you consider the damping effect of the landing gear. It would seem to me that the quicker you lower the collective the better chance you have. I've also considered the option of yawing into the roll, but I think if it got to that stage it would be too late anyway.

Consider my words eaten.