Early aircraft (with the smaller diameter blades) will be affected by the nose gear. So at gear extension the electric gen is disconnected to protect the hydraulics for the flight controls. It wiil stall at 130 kts(AMM 29-22-00). . Later a/c are fitted with a stall protection device that ensures that the pump power demand does not exceed the turbine output.
The RAT will adjust its pitch to maintain a constant RPM between 135 and 93 KEAS and will effectively be stalled below the lower speed. Our crews are told that the later RAT is good down to 125 kts or the flare. QRH for all types quote 140kts.
