How close can an aircraft taxi to an obstruction without a marshaller present?

The correct answer regarding how close an aircraft can taxi to an obstruction without a marshaller present is 25 feet. This distance is established to ensure safety and adequate clearance for aircraft when moving on the ground, particularly in congested areas where obstacles may pose a risk.

The regulation on the minimum distance is based on evaluating potential hazards and ensuring that there's sufficient space for the aircraft's wingspan and clearance zone. The 25-foot separation is intended to minimize the risk of collision or damage from unexpected movements or shifts in the surrounding environment. Maintaining this distance provides a buffer that keeps the aircraft safe while maneuvering, especially when the precise position of the aircraft, as gauged by visual signals from a marshaller, is not available.

In terms of operational procedures, this guideline helps reinforce situational awareness among ground crew and pilots, ensuring that all parties take necessary precautions when there is a lack of direct supervision from a marshaller, thereby enhancing overall safety on the airfield.