Aero 14 - Tips On Minimizing Smoke Events

TIPS ON MINIMIZING SMOKE EVENTS

The following tips are based on the review and analysis of in-flight smoke events on Boeing airplanes between November 1992 and June 2000:

Although not a serious risk for propagating fire, several events occurring immediately before or after airplane departure were attributed to engine or auxiliary power unit (APU) maintenance activity during the previous ground leg. Most operators have ground crew procedures for engine or APU runs following maintenance. For an operator with concerns in this area, a review of ground procedures that require engine or APU run may be appropriate.
Some known smoke events are directly preventable. Paper may come into contact with hot lighting, either in the cabin or crew rest areas. Food may be left in an oven or a coffeepot heated while empty.
Smoke or actual fire events have been initiated by repeated circuit breaker resets during ground troubleshooting. Even when performed on the ground, circuit breaker resets should be performed cautiously. Important considerations are the number of reset attempts, cooling time between reset attempts, and the stationing of maintenance crew monitoring for unusual sounds or smell.
A flight crew may be able to identify unknown smoke as air-conditioning smoke based on subsequent indication. In an air-conditioning smoke event caused by leaking engine oil, the first symptom noticed by the crew may be a burning odor of unknown origin. Subsequent engine indications might clarify an abnormal engine situation, and the corresponding bleed air source can be isolated.