To hold an airplane in level flight across a wide range of airspeeds, the pilot must coordinate which two parameters?

• A. Thrust and drag
• B. Thrust and angle of attack
• C. Lift and weight
• D. Bank angle and airspeed

Answer: (B)

In level flight across a wide range of airspeeds, you balance vertical and horizontal forces by adjusting two controllable factors: angle of attack and thrust. Lift must equal weight, and lift is set by the angle of attack (through pitch). Thrust must balance drag, and drag is controlled by engine power. So, by coordinating pitch (through angle of attack) to set the required lift and throttle to balance drag, you can maintain a steady altitude as speed changes. Bank angle isn’t the right pairing here in straight-and-level flight because banking changes direction and load factor, not the steady altitude at a given speed.