Fire, Ice, O2

Question 1

Engine/APU/MLG bay fire systems

Answer 1

Each has 2 loops (A and B) which link to an FDU (Fire detection unit)

Only 1 FDU common to all engines, APU and MLGs

If 1 loop fails, other continues and fire detection valid
* If the other fails AFTER 5 seconds from 1st failure, detection in that area is lost
* If the other fails LESS THAN 5 seconds after 1st, a fire is detected

Question 2

ENG FIRE pb sw push

Answer 2

Stops the aural fire warning and arms squibs

Closes the low pressure fuel valve

Closes the hydraulic fire shutoff valve

Closes the engine bleed valve

Closes the pack flow control valves, and

Shuts off the FADEC power supply

Question 3

Cargo bay smoke detection

Answer 3

Smoke detectors linked to a Smoke Detetection Function (SDF)

If smoke detected, Vent system isolates relevant cargo bay

2 extinguisher bottles can discharge agent into the forward or aft/bulk cargo compartments

1st one discharges over approx 1 min. Bottle 2 then discharges slowly to give approx 4 hours extinguisher concentration

Question 4

Engine Anti-ice

Answer 4

Each engine has its own anti-ice system with an independent hot bleed air source (operated with 1 anti-ice valve per engine)

Question 5

Wing anti-ice

Answer 5

Hot air from pneumatic system can be used to prevent ice accretion on slat 4, controlled by wing, wing anti-ice valves

Question 6

Other elec anti-ice

Answer 6

For:
Cockpit windows
Probes

Fully automatic, and operates as soon as any engine is started. Before engine start the crew can manually activate the system, via the PROBE/WINDOW HEAT pb sw

Question 7

Ice detection

Answer 7

2 sensors (next to pilots) sense ice and severe icing conditions

Question 8

Fixed O2 system deployment?

Answer 8

Cabin depressurization

Cabin alt > 13,800

Crew manually press MASK MAN ON button