Cowling

Engine cowlings must be structurally strong enough to withstand normal vibration, inertia forces, and airflow loads during operation.

The cowling design must allow fluids (like water, oil, or fuel) to drain quickly and completely when the aircraft is in typical ground or flight positions. These drains cannot empty where they might create a fire risk.

Materials matter based on temperature exposure: parts near the exhaust system or exposed to exhaust gases must be made of fireproof material that won't burn. All other cowling parts must be at least fire-resistant, meaning they can withstand heat and slow fire spread even if they're not completely fireproof.

This regulation ensures cowlings protect the engine while managing the significant fire hazards present in the engine compartment. Proper drainage prevents fluid accumulation that could feed fires or cause corrosion, while appropriate materials provide critical fire protection where heat and ignition sources are concentrated.

*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.*