What happens to the horizontal component of lift as bank angle increases (with airspeed unchanged)?

• A. Decreases
• B. Remains the same
• C. Reverses
• D. Increases

Answer: (D)

Banking tilts the lift vector, so part of lift goes horizontal to provide the turn, and part must balance weight vertically. For level flight in a turn, vertical balance requires L cos φ = W. As the bank angle φ increases, cos φ decreases, so the total lift L must rise: L = W / cos φ. The horizontal component of lift is L sin φ, which becomes (W / cos φ) sin φ = W tan φ. Since tan φ increases with φ, the horizontal lift component grows as the bank angle increases. With airspeed unchanged, the extra lift needed comes from a higher angle of attack to raise L, so the horizontal component increases accordingly.