TITLE 14 - AERONAUTICS AND SPACE

CHAPTER I - FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION

SUBCHAPTER C - AIRCRAFT

PART 25 - AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES

subpart e - POWERPLANT

25.959 - Unusable fuel supply.

The unusable fuel quantity for each fuel tank and its fuel system components must be established at not less than the quantity at which the first evidence of engine malfunction occurs under the most adverse fuel feed condition for all intended operations and flight maneuvers involving fuel feeding from that tank. Fuel system component failures need not be considered.

[Amdt. 2523, 35 FR 5677, Apr. 8, 1970, as amended by Amdt. 2540, 42 FR 15043, Mar. 17, 1977]