A Runway Safety Area (RSA) is a defined rectangular surface surrounding a runway that is prepared or suitable for reducing the risk of damage to airplanes in the event of an undershoot, overshoot, or excursion. It must be cleared of obstacles, properly graded, and capable of supporting the weight of an aircraft without causing structural failure to the landing gear.
Heard on the job
The airport had to install an engineered materials arresting system because the natural RSA was too short.