What is the effect of using a stopway on the Accelerate-Stop Distance Required (ASDR)?

Using a stopway affects the Accelerate-Stop Distance Required (ASDR) because it provides additional runway length available for the aircraft to decelerate after a rejected takeoff. A stopway is an area beyond the takeoff runway that is specifically designed to decelerate an aircraft in the event of a rejected takeoff.

When a stopway is available, it allows for enhanced braking performance, reducing the total distance needed to come to a complete stop. This means that when calculating the ASDR, the presence of the stopway can effectively decrease the distance required for stopping, which can also permit a higher V1 (takeoff decision speed). This increase in V1 indicates that the aircraft can continue the takeoff if engine failure occurs after reaching this speed, knowing that the extra length of the stopway can accommodate a safe stop if needed.

Increasing V1 while still ensuring that the overall ASDR is managed effectively demonstrates the operational safety net provided by having an available stopway. Understanding the implications of stopways on performance calculations is vital for ensuring safe aircraft operation.