Air New Zealand Tech Practice Exam

Natural lateral stability in an aircraft is influenced by several aerodynamic factors, specifically the design features that help maintain equilibrium during flight. The correct answer identifies the combination of wing dihedral and the side loads on the fin as key contributors to this stability.

Wing dihedral refers to the upward angle of the wings from horizontal. This design feature helps improve lateral stability by allowing the aircraft to return to a level flight position when it experiences rolling tendencies due to turbulence or crosswinds. When one wing drops, the dihedral causes the opposite wing to rise, counteracting the roll and stabilizing the aircraft.

The side loads on the fin also play a significant role. The vertical stabilizer (or fin) provides aerodynamic resistance to side-to-side movement. When the aircraft experiences a sideways force, such as from wind gusts, the fin generates a restoring force that helps bring the aircraft back to its original heading.

Together, these features create a self-correcting mechanism that enhances the aircraft's natural tendency to maintain lateral stability, minimizing the risk of unintended rolling motion. This is crucial for safe and efficient flight, providing pilots with better control and resilience against external disturbances.