engine firesthere are two main types of engine

Question

Engine fires:

There are two main types of engine fire that can occur when running gas turbine engines and they are dealt with in different ways.

1. Fire in the engine nacelle.

This type of fire will usually cause the engine fire warning system to function, although it may be spotted by the safety man outside. The engine should be shut down immediately. The engine fire handle should be pulled to isolate the nacelle. A fire extinguisher should be discharged into the nacelle, preferably the CO2 extinguisher by the safety man, if not available then one of the aircraft extinguishers. Inform the control tower, then shut down any other running engines, switch off power and evacuate the aircraft.

2. Fire in the core engine or external to the engine nacelle.

Fire can occur within the core engine especially after a ‘wet start' (a start which fails after fuel has been selected on). If insufficient time is allowed for fuel to drain from the engine or there is a fault in the drain system, fuel can pool inside the turbine area. On the next start this fuel ignites and flame and black smoke are seen in the exhaust. This may then be pushed out of the jet pipe by the airflow and spread onto the ground as a burning pool. This type of fire is usually spotted by the safety man. He should inform the engine operator, who should then cut off the fuel by shutting the throttle and or hp cock. The starter motor should continue to run to cool the engine and to push the fire out of the engine. The safety man should attempt to put out the fire by discharging CO₂ directly into the intake never up the exhaust (as CO₂ produces ice when discharged which can have an explosive reaction when directed into very hot metal). If the fire has spread out of the jet pipe this fire should also be tackled with the CO₂ extinguisher. When the starter reaches its maximum running time select the start master switch to ‘off' to cancel the start signal, pull the fire handle but do not fire any extinguishers. Make the aircraft safe i.e. shut down running engines and electrical power and evacuate. Beware!! sometimes burning fuel from this type of fire can run down inside the cowlings and cause damage to the engine.