Large transport category airplanes: Reciprocating engine powered: En route limitations: One engine inoperative

This regulation sets minimum climb performance requirements for large reciprocating-engine transport aircraft operating under Part 135 when one engine fails en route.

Standard method (paragraph a): The aircraft must maintain a specific climb rate with one engine inoperative at least 1,000 feet above terrain within 10 miles of the route. The required climb rate is calculated using a formula based on the number of engines and stall speed.

Alternate method (paragraph b): Operators may use an approved procedure that allows flying at a higher altitude where, after engine failure, the aircraft can reach a suitable alternate airport. The flight path must clear obstacles by at least 2,000 feet within five miles of track.

If using the alternate method, operators must account for reduced climb performance, ensure the aircraft can reach a predetermined alternate from any point on the route, meet standard requirements at the alternate airport, account for winds and temperatures, and coordinate alternate selection with appropriate weather minimums. Fuel jettisoning may be approved with proper training.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*