As a rule of thumb, which part of the aircraft determines if an airfield can be reached with an immediate turn and climb?

The wingtip of the aircraft plays a critical role in determining whether an airfield can be reached with an immediate turn and climb. When an aircraft experiences an emergency or requires a sudden change in direction, the wingtip's position relative to the ground and surrounding obstacles becomes crucial.

The wingtip's distance from the centerline of the aircraft is significant in assessing the aircraft's ability to maneuver safely, particularly during a turn and climb. Factors such as the aircraft's altitude, rate of climb, and the distance to the airfield all hinge on the aircraft’s ability to achieve a safe turn without encroaching on obstacles or restricted airspace. In essence, the wingtip's clearance during such maneuvers helps to ensure that the aircraft can successfully navigate its path to land, confirming the suitability of the chosen airfield for landing during an emergency situation.

This understanding underscores the importance of the wingtip in various aspects of operational safety and navigation, making it a critical component in assessing the feasibility of reaching an airfield after an immediate climb maneuver.