Definition
The length of the takeoff run available plus the length of the stopway, if a stopway is provided. It is the total runway distance an aircraft has to accelerate toward takeoff and then, if the takeoff is rejected, bring the aircraft to a complete stop.
Plain English
The total amount of paved surface a pilot can use to speed up for takeoff and, if something goes wrong, still stop safely. It includes the runway plus any extra paved area at the end designed for stopping.
Context Anchor
Seen in runway information, aircraft takeoff performance planning, and airport data used before departure.
Derivation
A 'stopway' is an area beyond the runway, not strong enough for normal operations but able to support an aircraft during a rejected takeoff. 'Available' means what is actually published and usable for the chosen runway, not just the physical pavement length.
Why Pilots Care
It determines the maximum takeoff weight an aircraft can safely use from that runway while still allowing a full abort without overrunning the paved surface.
Grounding Statement
Picture the aircraft starting its takeoff roll, the pilot deciding not to continue, and the airplane needing enough declared distance ahead to stop safely.
Intuition Check
Do not read available as meaning any pavement you can see. Here it means distance officially declared usable for this takeoff-and-stop case.
Example Sentence 1
Before departure, the captain checked that the accelerate-stop distance available on Runway 27 was greater than the distance required for their weight and conditions.
Example Sentence 2
With a tailwind, the accelerate-stop distance available became marginal for the planned takeoff weight.