O Boeing 747-400 Antes do procedimento de táxi diz (ênfase minha):
[...]
Flight controls .............................................. Check C
[...]
Hold the nose wheel tiller during rudder check to prevent undesired nose wheel movement.
Move the rudder pedals to full travel in both directions and verify:
- freedom of movement
- that the rudder pedals return to center
- correct flight control movement on the EICAS display
O FCOM (trem de pouso 14.20.3 - Descrição do sistema) diz ainda:
Nose Wheel and Body Gear Steering
Nose wheel and body gear steering is powered by hydraulic system 1.
Primary low speed steering control is provided by a nose wheel steering tiller for each pilot. Limited steering control is available through the rudder pedals. The tillers can turn the nose wheels up to 70 degrees in either direction. A pointer on the tiller assembly shows the tiller position relative to the neutral settings. The rudder pedals can be used to turn the nose wheels up to 7 degrees in either direction. Tiller inputs override rudder pedal inputs.
Eu me pergunto como os pedais do leme e os perfilhos estão conectados. Como o timão pode substituir a entrada do pedal? Presumo que os perfilhos se movam quando os pedais são usados, mas os pedais também se movem quando o timão é girado?