Nav8tor said:If for some reason a helicopter exceeds a critical angle of bank, the roll can not be corrected, and the helicopter rolls over. Common factors leading to excessive bank angles are takeoff/landing on the side of a slope, and catching a skid on the ground.
Carol said:Thanks, guys. I googled it. Should have done that first rather than put you to all that trouble.
The pilot is injured but not severely. (Played golf that afternoon.)
Nav8tor said:If for some reason a helicopter exceeds a critical angle of bank, the roll can not be corrected, and the helicopter rolls over. Common factors leading to excessive bank angles are takeoff/landing on the side of a slope, and catching a skid on the ground.
Carol said:The pilot is injured but not severely. (Played golf that afternoon.)
The typical dynamic rollover is a destroyed bird. The rotor is producing full (or nearly full) power as this takes place on pick-up and set down. When the helo rolls the main strike the ground once the mains are ripped off the helo will spin horizontally around its ground contact point and the tail rotor will strike the ground and rip the tail rotor off and the tail boom. Usually a total loss.Nav8tor said:How about the helicopter. Was there much damage?
That's not necessarily true. An attempt at a slope landing where the slope is too steep will result in a rollover if you don't immediately RAISE the collective when you realize that you ran out of cyclic.Chris Connor said:And the correction for this is actually not opposite correction it is down collective right now. Not in a second RIGHT NOW!!!!.
Chris
Nav8tor said:How about the helicopter. Was there much damage?
Bob,RotaryWingBob said:That's not necessarily true. An attempt at a slope landing where the slope is too steep will result in a rollover if you don't immediately RAISE the collective when you realize that you ran out of cyclic.
Chris, the Army Rotary Wing Flight manual describes this situation as a dynamic rollover (page 4-8), because you have one skid on the ground and it acts as a pivot point. That's also the way my primary CFI taught it, but then he's a retired Army pilot.Chris Connor said:Bob,
Yes you are right, but I don't think that it technically a "Dynamic Rollover". I believe that is considered a static rollover. Although it is a dynamic event, the heicopter would have rolled over with the engine off. The difference is that the rolling moment has not exceeded the critical angle. I agree completely with the corrective action you suggest for critical angle recovery caused by slope, not an obstruction.
Chris
Nav8tor said:If for some reason a helicopter exceeds a critical angle of bank, the roll can not be corrected, and the helicopter rolls over. Common factors leading to excessive bank angles are takeoff/landing on the side of a slope, and catching a skid on the ground.
RotaryWingBob said:Chris, the Army Rotary Wing Flight manual describes this situation as a dynamic rollover (page 4-8), because you have one skid on the ground and it acts as a pivot point. That's also the way my primary CFI taught it, but then he's a retired Army pilot.
Ok Bob. Yes what you are describing here is definitely Dynamic Rollover. I made an assumption when I read your other post. Since you mentioned hitting the cyclic stop I assumed your roll was to the down hill side.
Chris
Lance, I've never heard the term bank angle applied in this situation either, but I guess it does sort of work in this sense:lancefisher said:I don't think it's directly a function of "bank angle" at least as we fixed wing pilots relate to that. My understanding is that there has to be something restricting the body of the helicopter from moving to create a dynamic rollover event. Also I expect that you could cause the same problem about the lateral (pitch) axis if for example you caught a skid under a pipe and tried to power away forward.
lancefisher said:I don't think it's directly a function of "bank angle" at least as we fixed wing pilots relate to that. My understanding is that there has to be something restricting the body of the helicopter from moving to create a dynamic rollover event. Also I expect that you could cause the same problem about the lateral (pitch) axis if for example you caught a skid under a pipe and tried to power away forward.
There is a very similar situation for fixed wing pilots of tailwheel aircraft. If you open the throttle with the brakes on or the main wheels up against an obstruction (or stuck in the mud etc) you can easily bring the tail up far enough that no matter what you do next you will roll onto the nose.
Nav8tor said:True. Its a function of angle of the rotor disk. I was putting it in terms that are familiar to fixed wing pilots. I think its more likely to happen in roll, because in pitch there is more stability due to the mass of the fuselage, tailboom, empenage etc.