Fire Protection Flashcards
What is the overheat detection?
On the right engine nacelle
If temp exceeds 170 degrees
Will get CAP ‘NAC 2 OVHT’
What smoke detectors do the cargo compartments have?
Each compartment has one optical smoke detector
What is the smoke detector in the toilet?
Photo-electric smoke detector
Where is the smoke detection in the avionics bay?
Between the avionics compartment and the extract fan
CAP warning if smoke detected
What is the engine fire detection system?
Two identical loops A and B
Loops parallel to each other
Powered by the DC emergency bus
What should you do if you get a right NAC overheat warning?
- right engine power lever to ground idle
- condition lever to feather then fuel shut off
If on taxi, usually caused by a tailwind
- stop aircraft and increase power slightly
- shut down engine if overheat still exists after 30 seconds
What does the FCDU measure in the loop?
Measures the resistance and the capacitance
Will trigger a warning if resistance decreases and capacitance increases
Both loops have to detect a fire to trigger a warning
What fire warning will you get?
- CRC
- master warning
- fire handle will illuminate red
- FUEL SO light on condition lever
- ENG FIRE light on CAP
What should do if a loop FAULT light illuminates?
Must be deselected otherwise the loops will not detect a fire
Only the other loop will be used to detect a fire
If the loop is broken can it still detect a fire?
If there is one break then yes as the loop is still connected to the controller, if there are two breaks then no
What will happen in a bleed leak?
You could still get a fire warning but the bottle should not be used
What does the fire protection consist of?
Two fire bottles containing halon gas pressurised to 600 psi
Located on each side of the fuselage
Either bottle can be used for either engine
When will the fire handle light extinguish?
Only when the fire is no longer detected
What will pulling the fire handle do?
- It will arm the associated squibs on each fire bottle
- The SQUIB light will illuminate
- close the engines bleed and high pressure bleed valves
- closes the engines associated engine pneumatic de ice valve and isolation valve
- trips the associated DC and ACW generator fields
- closes the engines low pressure fuel valve
- runs the electronic feathering pump to feather the propeller
Why should you shut down the engine before pulling the fire handle?
Because pulling the fire handle closes the low pressure fuel shut off valve and this could prevent the restarting of the engine later
