What is a key feature of rotary-wing aircraft?

A key feature of rotary-wing aircraft is their ability to hover in midair. This unique capability is primarily due to the design and function of the rotor system, which allows the aircraft to generate lift while remaining stationary above a specific point. Unlike fixed-wing aircraft that require forward motion and a runway to generate lift, rotary-wing aircraft can take off, land, and maneuver in tight spaces thanks to their rotors. This makes them particularly valuable for a variety of applications, including search and rescue operations, aerial photography, and military missions, where hovering capability is essential.

In addition to hovering, rotary-wing aircraft can perform vertical takeoffs and landings (VTOL), adding to their versatility. The other choices presented do not capture this defining characteristic of rotary-wing aircraft. For example, the ability to travel long distances without landing is more associated with fixed-wing aircraft, which are designed for efficient, sustained forward flight. The requirement for a long runway is also relevant to fixed-wing aircraft, as they rely on the generated lift through forward motion, and aerodynamic shape for lift does not apply solely to rotary-wing systems, given that their lift is produced by rotating blades rather than their shape alone.