13.9 Lighting Flashcards
Describe the intensity, angle and plane showing of the all navigation lights?
Port - red, 5 candelas, 110° from dead ahead in the horizontal plane, 90° above and below the horizontal plane
Starboard - green, otherwise as port
Rear - white, 20 candelas, 70° right and left of dead astern, 90° above and below the horizontal plane
What must all light covers and colour filters be?
- At least flame resistant
- May not change colour and shape or lose any appreciable light transmission during normal use
What are the requirements of navigation lights, which coincides with the requirements of an essential circuit?
Must be in a single circuit, controlled by one switch, whose power source is via a circuit breaker
To comply with the ‘Rules of the Air Regulations 2015’, what do some aircraft have?
Two filaments in each navigation light, each filament driven from a different power supply
What are the requirements for anti-collision lighting of aeroplanes (CS25)?
- Aeroplanes over 5700 MTWA
- ± 75° around the horizontal plane
What are the requirements for anti-collision lighting of helicopters (CS29)?
± 30° around the horizontal plane
What is the principle of operation of the rotating reflector?
Filament lamp unit and a motor
Motor drives a reflector, to establish a beam of light which rotates at a constant frequency
All components are enclosed in a red lens cover
What is the effective flash frequency of a rotating reflector?
40 to 100 cycles per minute
What power normally operates a rotating reflector?
28V DC
or
115V AC for the motor and 28V DC for the lamp unit
How is the beam reflected in a rotating reflector?
One half of the reflector is flat, emits a narrow high-intensity beam of light near the horizontal
Other half is curved, increases the up and down spread of the emitted beam
Describe the rotating beacon?
Two filament lamps mounted in tandem, and pivoted on their own axis
One half of each lamp forms a reflector
One complete revolution is two flashes
What is the principle of strobe lighting?
Capacitor-discharge flash tube
What does CS25 state about the colour of aircraft strobes?
Either aviation red or aviation white
What does CS29 state about the colour of aircraft strobes?
Must be aviation red
Describe the power supplies for a large aircraft strobe light?
Power supply unit converts input power of 28V DC or 115V AC into a high DC output, usually 450V
What is the typical flashing frequency of a large aircraft strobe light?
70 per minute
What precautions must be observed with regards to strobe lights?
- Eye protection against high intensity light
- Electric shock
- Burning
- Stroboscopic effects
- Ground operation
What eye problems might UV emissions cause when viewed at close range?
UV keratitis
What is the normal ground operation of strobe lights?
Red
What are the maintenance practices which apply to all lamp assemblies?
- Lint free cloth for cleaning
- Keep fingers away from glass
- Ensure lamp correctly positioned and secure
- Cable connector security inspection
- Examine for streaks which is a symptom of gas leaking through the glass through a hairline fracture
What power requirements are there for high intensity search lights?
100V DC and 10kV AC
What are the safety precautions when working on a high intensity search light?
- Never work on your own
- Wait until it has cooled to ambient temperatures
- Disconnect power first and use a digital multimeter to ensure that all voltage has discharged
- Wear correct PPE; full face protection mask, heavy duty gloves, jacket
- Warn all personnel in the vicinity
- Never look directly at the lamp when it is on
- May cause flammable materials to catch fire at distances of less than 3 metres
What power is consumed by the landing lamps and taxy lamps?
Landing lamp - 400W
Taxy lamp - 250W
What extinguishes the taxy lamp on retraction?
Undercarriage proximity or microswitch
On a combined landing and taxy lights assembly, what can cause automatic retraction?
Speed switch is interlocked when the limit is exceeded
What switches off the lamp when the combined landing and taxy lights are retracted?
Microswitch or proximity sensors
When will an aircraft be allowed to fly at night where icing conditions are forecast or exist?
If there is a means of illumination to determine if areas of the wing, that are critical to lift, have an accumulation of ice on them
What is the power rating of ice inspection lights?
60W to 250W
When will the lights come on in the baggage compartment, and what component allows this?
When the door is open, the light comes on, through the closed contacts of a microswitch
Where does the power for maintenance lights come from?
28V DC hot battery busbar
What is integral lighting normally known as?
Wedge or front lighting
What is the purpose of wedge lighting?
Distsributing light evenly across the dial
How is absorption of light ensured in wedge ‘B’ of an integral light?
Painting its outer part black
What is the sector of light of a pillar lamp?
Arc of approximately 90° to a depth slightly less than 2” (5cm)
What does a bridge light provide which is not provided in a single pillar lamp?
Total loss of illumination cannot occur as a result of failure of one circuit
Describe an electroluminescent panel?
Consist of a thin laminate structure in which a layer of phosphor is sandwiched between two electrodes, one of which is transparent
Requires AC for its operation
What does the luminescent intensity of the phosphor in a electroluminescent panel depend on?
Voltage and frequency of the AC supply
What is the disadvantage of using a rheostat in controlling the lighting intensity of cabin lights?
Power is dissipated as heat generated in the rheostat
How can the disadvantage of using a rheostat to control the intensity of cabin lighting be overcome?
Using a transistor, which requires only very low voltage levels over its conducting range
What is the prinicple of operation of storm lighting?
Will turn certain lights on to full, ie glare shield lights, cockpit dome lights, instrument lights
Allows a night blinded pilot to see aircraft instruments
What are ballast units for?
To start fluorescent tubes, then limit the current to them
How are entry lights turned on, with no internal aircraft power available?
Applying external power plug, which energises ‘external power sensing relay’
28V DC is applied from the hot bus
When the information signs switch is in AUTO, when will the ‘seatbelt’ relay energise and what will this cause?
When the flaps are extended, the microswitch in the flap lever completes the earth for the ‘seatbelt’ relay
The ‘fasten seat belt’ and ‘return to seat’ signs come on
When the information signs switch is in AUTO, and after flaps are extended, what will then cause the ‘no-smoking sign’ relay to energise?
The microswitch to energise the relay is made when the landing gear lever is placed in the ‘down’ position
‘No smoking’, ‘return to seat’ and ‘fasten seat belt’ sign will come on
When will a low tone chime in the passenger address system?
When the ‘no smoking’ or ‘fasten seat belts’ circuits are energised or de-energised
When is a high tone chime sounded over the passenger address system?
When the flight attendant call system is pushed
What will be the indications when a flight attendant call switch is pressed in the lavatory?
Amber light
High tone chime
When ground power is applied, what is the light intensity in the toilet?
Full intensity
During normal flight, when is the lavatory toilet lighting at full intensity?
When the door is locked
What light within the lavatory is always on, regardless of door position, and what power does it use as long as the aircraft has its own power?
Dome light
28V DC
What are the emergency lights battery packs normally made from?
Nickel-cadmium
Silver-zinc
How are the emergency battery packs maintained in a fully charged condition?
Trickle charge from the normal aircraft busbars
With regards to emergency lighting, what warning will the EICAS/ECAM give?
A caution message if the system is not armed
How are emergency dome lights and emergency exit placards supplied with power where emergency power is supplied, or in the event of total aircraft power failure?
Even if the control switch is off (fed from the primary bus), power is supplied by the emergency battery
What is the minimum requirement, in terms of time, for which emergency lighting is required to illuminate?
10 minutes
What is the requirement for passenger and crew compartment doors and emergency exits in an aircraft?
Must be of a regulation dimension, easily identified, suitably illuminated and simply opened
What is the purpose of floor proximity lighting?
Provide visual guidance for cabin evacuation when all sources of cabin lighting above four feet are obscured by smoke
If a self-illuminating fluorescent strip has been in low light conditions for an extended period, how long would it take to charge it?
2 hours of normal light
If the cabin attendant switch for cabin emergency lights is selected on, what will be the state of the emergency lights?
On, regardless of position of cockpit emergency lighting switch and 28V DC power availability
What indicates an over the wing emergency exit with regards to the emergency lighting system?
Red LED floor proximity lighting at the bottom of the passenger aisle seat
Describe a self-illuminating exit sign?
Glass tube filled with tritium gas which is coated with a phosphor layer, placed in a plastic container
Known as Gaseous Tritium Light Source (GTLS) or beta light
When and in what way does a GTLS become dangerous?
If the case is broken
Dangerous to breathe the gas, or allow it to be absorbed by the skin
What are the safety precautions which must be adhered to with regards to a broken GTLS?
- Keep all personnel away
- Ventilate the area for the time required in the AMM
- Wear the correct PPE as detailed in the AMM
- Put it in a metal container labelled ‘Danger Radioactive Material’
- Dispose of under the current regulations for radioactive materials
