fire protection

APU fire warning horn will sound on the ground for:

APU fire or fire test — On the ground, the APU fire warning horn is part of the APU fire warning system and also sounds during the fire/overheat test. [Ref: Chapter 8 — Fire Protection — 8.10.6]

Where is the APU ground control panel located?

Right body gear wheel well — The APU ground control panel is located at the right body gear wheel well, providing external access to APU controls and fire indications. [Ref: Chapter 8 — Fire Protection — 8.20.1]

There is a dual loop fire detection system in each of the engine compartments. True or False?

True — Each engine nacelle has a dual-loop fire detector. In normal dual-loop operation, both loops must detect the fire condition to generate the engine fire warning. [Ref: Chapter 8 — Fire Protection — 8.20.2]

There is a single fire detection system for the APU compartment. True or False?

False — The APU compartment has a dual-loop fire detector, not a single-loop system. Either loop detecting a fire activates the APU fire warning. [Ref: Chapter 8 — Fire Protection — 8.20.2]

There is a single fire detection system in each main gear wheel well compartment. True or False?

True — Each main gear wheel well is protected by a single fire-detector loop. [Ref: Chapter 8 — Fire Protection — 8.20.2]

All extinguishing discharge squibs are tested for electrical continuity. True or False?

True — The squib test checks electrical continuity of all extinguisher discharge squibs and also tests the squib control circuit. [Ref: Chapter 8 — Fire Protection — 8.20.6]