Aircraft Cabin Communication Systems

What is the primary purpose of a Master Call Light panel in an aircraft cabin?

What color is the Master Call Light for a passenger service call?

What happens to the cabin interphone crew call light when the receiving station handset is removed from the cradle?

Which of the following events does not trigger a Master Call Light?

What is the purpose of the chime annunciations in the Master Call Light system?

Where are Master Call Light panels typically located in the cabin?

What is the purpose of the All Call (55) feature on the Master Call Light panel?

What is the visual indication of a lavatory service call on the Master Call Light panel?

Master Call Light Panel

Provides cabin crew with visual indication of initiated calls or events requiring attention
Located throughout the cabin near cabin crew stations and some galleys

Call Initiation

Calls can initiate from flight deck, cabin crew stations, passenger seats, or lavatories

Call Indicators

Cabin interphone call lights and attendant station chime annunciations used as call indicators at receiving location
Some call types cause call light to flash
Cabin interphone crew call light extinguishes when receiving station handset is removed from cradle

Master Call Light and Chime Definitions

All Call (55): pink light (flash) with Hi/Lo Chime
Attendant All Call (54): pink light (flash) with Hi/Lo Chime
Attendant to Attendant: pink light (steady) with Hi/Lo Chime
Crew Rest Smoke: amber light (flash) with Hi/Lo Chime (continuous)
Attendant Alert (Waste Tank Full or Inoperative): no light or chime
Lavatory Service Call: amber light (steady) with Hi Chime
Lavatory Smoke: amber light (flash) with Hi/Lo Chime (continuous)
Passenger Service Call: blue light (steady) with Hi Chime

Call Light Illumination

Amber Master call light (MCL) illuminates:
- Steady: Lavatory service call
- Flash: Lavatory smoke
Blue attendant call light illuminates:
- At Master Call Light panel (MCL)
- At Passenger service unit (PSU)

Master Call Light panels are used in aircraft cabins to indicate calls or events that require attention from cabin crew. They are located throughout the cabin and use call lights and chime annunciations as indicators.