What happens to the radius of turn if the angle of bank is held constant while airspeed increases?

When the angle of bank is held constant and the airspeed increases, the radius of turn increases. This is because the centripetal force required to maintain a turn is influenced by both the speed of the aircraft and the bank angle.

In a banked turn, the horizontal component of lift acts as the centripetal force that pulls the aircraft into the turn. As airspeed increases, the aircraft requires a greater radius to maintain level flight because the increased speed generates a higher load factor. Since the bank angle remains constant, the lift produced also remains constant; therefore, in order to balance the increased centrifugal force from the higher airspeed, the aircraft must turn with a larger radius.

This principle is essential for pilots to understand, as it affects maneuvering and navigation during flight. In practical terms, if a pilot attempts to turn at a constant bank angle while speeding up, they will notice that the aircraft will begin to turn more widely, rather than tightly.