Low-G pushovers not simulated.

[deathbysybian]

Probably the most significant missing physics simulation from the model is that of low-G-pushovers.

 

Because the helicopter is effectively "hanging" from the rotor blades and the tail-rotor thrust is above the vertical center of gravity there should be a strong roll during a low-G pushover.

 

During normal forward flight the weight of the helicopter hanging from the rotors makes the off-axis thrust from the tail rotor insubstantial.

 

However, if a near zero-g condition is created that is no longer the case. The thrust from the tail-rotor causes the body of the helicopter to roll away from the thrust. The pilot sees this as a uncomanded hard left roll. The incorrect response is to counter with right cyclic. This induces mast bumping (because the main rotor is still horizontal) and main rotor separation occurs.

 

The correct action is to pull up, which re-loads the rotor blades and the body of the helicopter will re-orient itself upright.

 

It's disappointing this isn't simulated because it's a real effect that has killed many pilots of the UH-1.

 

The R-22/44 which has a similar head even has low-g pushover prohibited stamped on the cyclic.

Edited October 1, 2020 by deathbysybian

[AW139]

Mast bumping is simulated, but not sure to what extent the events leading up to it are. I have purposely done a pretty hard push-over, and sheared the mast.