by Groucho » Sat Mar 30, 2013 11:23 am
Raptor wrote in Sat Mar 30, 2013 6:28 am:So i did a small experiment by disabling tail rotor & adding 2 thruster's on tail end, but its not exactly like working of NOTAR system that is using pressure difference to producing an anti - torque effect.
In fact the concept has some implications on the FDM. Using parts of the main rotor downwash will lead in a reduced lift of the backward running blade. As the MD900 has a counter-clockwise turning rotor the lack of blade lift will (caused by the approx. 90° phase shift of the blade effect) cause the helicopter to bank to the right. So any pitch change will show this effect more or less. I have no idea if the helicopter onboard system compensates this by eg. applying more cyclic input to the rear blade.
A positive effect: More pitch usually means more torque moment on conventional helicopters. As the NOTAR relies on the rotor downwash more pitch also means more air flow around the tail boom meaning more anti-torque effect here automatically. So the necessary compensation force is less.
In reality the dependent effects are a bit more complicated but we can leave it this way as this is the primary implication for the FDM.
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Callsign: D-HARP
Flight locations: TNCM, TKPK, EDNY, LOWI
Aircrafts
Helis: EC130, Bo105, UH-1, R22
Twins/Jets: Aerostar, CRJ-200