Serving Midwest Aviation Since 1960

Flight Controls in Four Phases

It's no wonder that students become frustrated with controlling an aircraft when there doesn't seem to be consistency between flight control inputs and aircraft response creating thoughts and comments such as, "I'm never going to get this."

Learning to fly might be less onerous if students understood that flight controls have a unique purpose in each phase of flight. Applying the same inputs to ailerons, rudder and elevator, no matter which "Phase" an aircraft is in is where things become frustrating. To help promote understanding of the changing roles flight controls play, let's analyze the aviating process at Taxi, Takeoff, Cruise, and Landing.

Taxi – When taxiing, students' first experience with negative transfer of learning is when they attempt to turn the aircraft with the yoke. Ailerons have no effect when attempting a turn on terra-firma. That task is the domain of the rudder. When taxiing with a quartering tailwind, ailerons and elevator provide a supporting role, by being deflected down, on the windward side, to reduce the tendency of the wind to lift the tail or upwind wing. When taxiing into a quartering headwind the upwind aileron should be up and elevator neutral in a tricycle gear aircraft. On a tail-wheel aircraft, the elevator is held in the most rearward position to keep the tail on the ground.

Take-off – During initial ground roll, the rudder continues to be the primary means of directional control with the ailerons positioned to prevent unwanted premature lifting of the upwind wing. At liftoff, the roles immediately switch, as the ailerons assume directional control and the rudder assumes it's role of controlling yaw. This important change is where students usually correct for left turning tendency with right bank, which results in an uncoordinated climb.

Cruise – When maneuvering in cruise, flight controls assume their primary functions with aileron inputs for turns, rudder deflected in the same direction to eliminate yaw, and elevators to control pitch.

Landing – In the traffic pattern, flight control inputs are standard as in cruise...until final approach. In a calm wind, nothing changes. However, with a cross wind, to maintain proper ground track, rudder and aileron applications change. The ailerons are banked to maintain a straight ground track, while the rudder reverts from eliminating adverse yaw, to creating yaw (producing a side slip) to maintain parallel alignment to the center-line at touchdown.

Keeping the fundamental laws of aerodynamics in mind while engaged in any of the four phases, or transitioning from one to the other, will help students establish good flying habits that won't have to be re-learned as they advance to higher performance aircraft.

 

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