AAS focused study Flashcards
Function of a start generator system?
(Book 1)
- A DC motor is used in a starter generator system to start the aircraft engine
- It can then be used as a generator to supply the aircraft DC bus and recharge the battery.
- Still used in light aircraft’s where weight is a major consideration
Bleed air sources - the starter motor is rotated by 3 main power sources, these are?
(Book 1)
- Air intake from an external ground supply
- APU
- Bleed air from running engine
Purpose / function of an APU in an automatic starting system used in modern aircraft’s?
(Book 1)
- Forms integral part of the engine starting system
- Supply low pressure air
- Commands / controls signals to components in the engine control system
Control and indication system - what does the GTS stand for and indicate?
(Book 1)
- Gas turbine start caption in the cockpit
- Comes on to indicate that the APU is running and ready to supply low pressure air
Propeller synchro phaser system - function and purpose?
(Book 2)
- Allows for matching of engine RPMs
- Allows the pilot to select a phase relationship between props
- Phase relationship can be varied to minimise vibration and noise
Propeller synchrophaser target - where is it installed?
(Book 2)
- Installed on the on the de-icing platter located immediately adjacent to the back of the propeller
- A magneto pick up is installed on the propeller brush block
Electric-hydraulic operation block diagram - name the components?
(Book 3)
- Control column transducer (Yellow box)
- Attitude and rate (Red box)
- Flight control computer (Blue box)
- Airspeed altitude (Orange box)
- Servo unit (Green box) / LVDT (Attached - Red rectangle) !!!!
- Control surface (Wing shape)
Undercarriage indication system - what do the following symbols represent?
- Miniature wheel
- Striped display (Barbers pole)
- Word ‘UP’
(Book 4)
Refers to the positioning of landing gear as below -
Miniature wheel: ‘Down and locked’
Striped display (Barbers pole): ‘In transit’ or when elec power is OFF
Word ‘UP’: ‘Up and locked’
Landing gear warning system - Function of the differential pressure switch?
(Book 4)
Will close when the airspeed falls below a predetermined level (this speed will vary for different aircraft types)
Skid control system - Functions?
(Book 4)
- Normal skid control
- Touch down protection (Weight on the wheels and travelling over 25kph) !!!!!!!!!!!!
- Fail-safe protection
Typical anti-skid system block diagram - Components?
(Book 4)
- Brake /rudder pedals (As displayed)
- Brake control servo valve (Middle top box)
- Skid control valve (Middle box)
- Skid control box (Middle bottom)
- Skid control generators (on wheels x 2) !!!!
Navigation lights - Where are they located?
Red
Green
White
(Book 5)
Red - Left (Port)
Green - Right (Starboard)
White - Rear
Anti-collision lights - Typical frequency of flashing?
(Book 5)
80 - 90 cycles per minute
Thermocouple sensor - Construction?
(Book 5)
- 2 dissimilar metals joined at both ends to form a cold and hot junction
- If 1 junction is heated, current proportional to the difference in temperature between the 2 junctions will flow in the circuit
Light refraction system - Components of the light refraction smoke detection system?
(Book 5)
Left to right
- Air to compartment
- Pilot light
- Test LED
- Photo diode
- Light trap
28VDC
Extinguisher bottles / tanks - Components?
(Book 5)
- Squib!!!!!!!!
- Elec harness
- Discharge outlets
- Fill fitting and safety cap
Combustion heaters - requirements?
(Book 7)
- Fuel to burn
- Ignition to ignite the fuel
- Combustion air to support the flame
- Ventilation air carry the heat where it is required
Supply and exhaust systems - An equipment cooling system can use either 1 or both of what systems to remove heat from equipment?
(Book 7)
- Supply system
- Exhaust system
Function of low flow sensors?
(Book 7)
- Equipment cooling systems uses low flow sensors to monitor the cooling quality of air through the system
- When a low flow occurs, the low flow sensor supplies an alarm signal to the flight deck for notifications
On medium to large pressurised aircrafts, the ventilation system is an extension of the air-cycle air conditioning system. Air is distributed around the interior of the fuselage using what?
(Book 7)
Ducting and vents placed at locations around the cockpit and cabin
Air cycle, air-conditioning system - What is used if the air is too dry?
Humidifier
Fuel control unit - A fuel control unit is installed on a turbine based engine to regulate the supply of fuel to the combustion section of the engine. What 3 ways can this be achieved?
- Hydro-mechanical
- Hydro-mechanical/electronic
- Fuel authorised digital engine control (FADEC) !!!!!
Fire extinguishing agents - Commonly used agents? and precautions to keep in mind?
- Carbon dioxide
- Freon (Halon 1301)
- Methyl bromide (Halon 1001)
- Chlorobromomethane (Halon 1011)
- Carbon tetrachloride (Halon 104)
- Dibromodifluoromethane (Halon 1211)
- Bromotrifluoromethane (Halon 1301)
No unauthorised discharge
Flood lights - common types and uses in aircrafts?
Floor lights
- Mounted at floor level to illuminate walkways and stairways
Doom lights
- Usually situated overhead to illuminate an area such as: the cockpit, passenger, cargo or galley area
- Typically white light
Aircraft lighting - Operation of trans-illuminated panels?
- Sometimes known as edge lighting
- Method of using to illuminate etched inscription on the cockpit panels to make them readable under night conditions
Strobe lights - frequency of flashing?
70 times per minute
Prop control system - what is the brains of the system?
Prop governor
HEIU - what does it stand for? 2 classifications?
High energy ignition unit
- High joule
- Low joule
DC tremor operated HEIU - Normal rate of sparks?
60 - 100 sparks per minute
HEIU - Safety precautions?
Removal - Disconnect input first
Installation - Connect output first
- Allow the recommended time to elapse before touching it
Magneto ignition system - components?
- Magneto
- Auxiliary starting device
- Ignition switch
- Ignition harness
- Spark plugs !!!!!!!!
Air cycle, air-conditioning system - Temperatures to keep in mind?
200 degrees: from the engine compressor stage
5 degrees: after travelling through the heat exchangers, compressor, turbine, water separator and humidifier
18 degrees - 30 degrees: final result with 200 from the engine and 5 from the cooling process - both found in the mixing chamber
