Cabin Fire and Smoke
A cabin fire can come from an electrical fault, fuel leak, cigarettes (banned in most cockpits) or items brought on board. Smoke without visible flames is its own emergency.
Source: POH (binding), FAA-H-8083-3B Chapter 17.
General procedure for cockpit smoke
- Identify the source (if quickly possible): smell (electrical, fuel, heater), visible origin.
- Emergency shut-off of probable source:
- Electrical: master OFF, avionics master OFF.
- Heater: cabin heat OFF, all heat/defrost controls OFF.
- Fuel leak: fuel selector OFF (only if enough altitude for glide).
- Ventilation: cabin vents open, windows opened carefully (for crew smoke evacuation).
- Oxygen masks if installed (Subject 040 — caution: NOT 100 % O₂ in an electrical fire → increased fire risk).
- Fire extinguisher ready.
- Land ASAP: Mayday, squawk 7700, nearest suitable field.
Specifics
Fuel smell in cabin
- Fuel leak — likely from tank line or carburettor.
- Cabin heat OFF (in case heat-muff defect is involved).
- Vents open.
- Land immediately — fire risk enormous.
Electrical (plastic / insulation)
- See lesson "Electrical fire" — master OFF priority.
Heater defect (heat-muff crack)
- Cabin heat OFF.
- Vents to max fresh air.
- CO poisoning possible (see next lesson) — watch symptoms closely.
Smoke-evacuation technique
- Before opening, ensure no people are directly at the window (wind, pressure differential).
- Cabin vents maximised, cabin heat OFF.
- On high-performance aircraft: smoke hood (emergency breathing protection), if available.
Crew and passenger brief before forced landing
- Crash position: head down, arms over head, legs braced.
- Doors unlatched.
- Glasses / loose items removed.
- Quick release after stop, away from aircraft.
Prevention
- No ignition sources in cockpit (lighters, matches — even when stored).
- Fabrics / blankets stowed safely, not over the heater.
- 100-hour inspection of heater heat-muff (for cracks).
- Functional check of extinguisher (every 6 months).