What primarily influences airplane wing loading during a level coordinated turn in smooth air?

Wing loading during a level coordinated turn is primarily influenced by the angle of bank. When an airplane banks, the lift vector tilts with the wing, causing an increase in the load factor on the wings. This increase in load factor indicates that the wings must support not only the weight of the aircraft but also an additional load due to the centrifugal force created by the turn. The steeper the angle of bank, the greater the load factor and consequently the greater the wing loading.

In a level turn, maintaining altitude while turning requires more lift to counteract the increased load factor. This relationship underscores the direct impact of bank angle on wing loading during a turn, as opposed to other factors such as rate of turn, true airspeed, or altitude, which do not influence wing loading in the same direct manner.