Flying the single engine Huey on SAR work we had a simple landing guide as to performance capability, although forget the numbers now. Straight and level at 60 knots 500' above landing site and note TQ, pull to rotor bleed or reaching engine limit and note TQ. If TQ difference exceeded a particular figure (forget) OGE was possible, if below but above another figure (forget) IGE was possible, if below a certain figure (forget) a run on would be required, other figures gave a zero/zero capability. Naturally you only applied if you were into wind.
