Performance requirements: Aircraft operated over-the-top or in IFR conditions

This regulation sets climb performance requirements for Part 135 aircraft operating over-the-top (above cloud layers) or in IFR conditions with passengers.

Basic rules: Single-engine aircraft cannot carry passengers over-the-top at all. Multi-engine airplanes must be able to climb at least 50 feet per minute with one engine inoperative at the route's MEA or 5,000 feet MSL, whichever is higher. Multi-engine helicopters operating offshore have a lower threshold: 50 fpm climb capability at MEA or 1,500 feet MSL.

Exceptions: You can operate over-the-top without meeting these performance requirements if current and forecast weather allows VFR flight below the clouds for the entire route (including takeoff and landing) until one hour past ETA. Additionally, multi-engine aircraft can operate over-the-top if conditions permit VFR descent or continuation if an engine fails; single-engine aircraft need only VFR descent capability available.

*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.*