APU Fire Detection - As the temperature of the detector increases to a predetermined limit, the detector senses a fire condition. The APU fire switch remains illuminated until the temperature of the detector has decreased below the onset temperature.
There are two fire detection loops installed on the APU.
A single fire detection loop is installed on the APU.
The engine fire switches are normally locked down to prevent inadvertent shutdown of an engine:
If smoke / fumes are uncontrollable, the crew is supposed to descent to the lowest safe altitude and at 14000 or below, the PRESSURIZATION MODE SELECTOR should be positioned to MAN while the OUTFLOW VALVE switch should be opened. What is the main cause of the OUTFLOW VALVE operation?
The outflow valve can take up to 20 seconds to open.
When the Extinguisher Test switch is held in the 1 or 2 position, 3 lights illuminate indicating:
The power source for Engine Fire Extinguishing is the:
A dual fire detector loop is installed in the main wheel well
A single fire detector loop is installed in the main wheel well. As the temperature of the detector increases to a predetermined limit, the detector senses a fire condition. The WHEEL WELL fire warning remains illuminated until the temperature of the detector has decreased below the onset temperature.
Holding the TEST switch to the FAULT/ INOP position:
After a wheel well fire, if the landing gear must be retracted for airplane performance, leave the landing gear extended for ___ minutes after the WHEEL WELL fire warning light has extinguished.
Illuminated (amber) FAULT with the overheat detector switch in NORMAL it indicates both detector loops for an engine have failed. With the overheat detector switch in A or B it indicates the selected loop for an engine has failed. MASTER CAUTION and OVHT/DET system annunciator lights also illuminate.
MASTER CAUTION and OVHT/DET system annunciator lights do NOT illuminate.
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With the OVHT DET switch in the B position:
Placing the TEST switch in the FAULT / INOP position tests:
Cargo compartement smoke detection is powered by:
Cargo compartment fire extinguishing is powered by the hot battery bus.
Illumination of the APU DET INOP light will also cause the MASTER CAUTION and OVHT/DET annunciator lights to illuminate.
Some of the indications for an engine fire warning are MASTER CAUTION & OVHT/DET annunciator lights, the ENG OVERHEAT light, the Master FIRE WARN lights and the red fire switch light. What are the other indications?
The APU horn in the main wheel well can be silenced by:
The APU Horn Cutout switch in the main wheel well will silence:
The Engine Fire Extinguisher system contains:
Main wheel well fire protection consists of fire detection powered by the:
In case of Cargo Fire, the Cargo Fire (FWD / AFT) Warning Lights are illuminated red.
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The Engine Fire Extinguisher system contains:
The power source for the APU Fire Detection is the:
Holding the TEST switch to the OVHT/FIRE position with AC on the busses will illuminate the:
The system contains a fault monitoring circuit. If one loop fails with the OVHT DET switch in NORMAL, that loop must be manually deselected and the remaining loop functions as a single loop detector.
If one loop fails with the OVHT DET switch in NORMAL, that loop is automatically deselected and the remaining loop functions as a single loop detector.
APU fire protection consists of:
Please select 2 correct answers
All switches on the Fire Panel are in their normal positions. The TEST switch is then held in the OVHT/FIRE position and all normal test indications are observed. The FAULT light is also observed to be illuminated which would mean that:
Pulling the engine fire warning switch up:
Engine Overheat and Fire Detection - If the OVHT DET switch is positioned to A or B, the system operates as a single loop system. The non-selected loop is not monitored. If the selected loop fails, the FAULT light illuminates and the system is inoperative.
The Engine Overheat and Fire Protection system has:
During an OVHT/FIRE test the No 1. Fire Handle light and associated overheat light do not illuminate. What does it indicate?
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If the DETECTOR FAULT light is illuminated (amber), a minimum of one loop in one or both cargo compartments have failed.
BOTH loops in one or both cargo compartments have failed.