Aircraft Flight Compartment Systems Quiz

Boeing B747-400 ATA 33 Lights

• Revision: 1SEP2009
• Document type: Training manual
• Intended use: For training purposes only
• Copyright: Lufthansa Technical Training (LTT) owns all rights to training documents and software. Any use outside of training is prohibited.
• Maintenance Level: 3
• Aircraft model: Boeing B747-400
• ATA 33 Code: 33
• Topic: Lights
• Content notes: This document details the various light systems on the Boeing B747-400, including their functions, descriptions, maintenance procedures, and diagrams. It's specifically for Level 3 maintenance.

General Introduction

• Types of lamps: White incandescent and fluorescent lamps are used in all aircraft light assemblies. Colored illumination (e.g., instrument panel indicators) is achieved using colored lenses.
• Check lamp identification numbers: Before installing lamps, always check the identification number to ensure correct voltage rating. Incorrect voltage ratings can damage circuitry.
• Lamp Usage Chart: Refer to the Lamp Usage Chart for information on locating all lamps. Refer to Standard Schematic Manual (SSM) 33-00-01.

Flight Compartment Lighting

• Areas illuminated: Flight compartment lighting illuminates control cabin work areas and control panels.
• Master dim and test system: A master dim and test system allows pilots to test indicator lights and select predetermined light intensity levels.

Passenger Compartment Lighting

• Location and functionality: Lights illuminate seating areas, aisles, entrances, lavatories, galleys, and crew rest areas. Includes call lights and information displays for passengers and crew.

Cargo and Service Compartment Lighting

• Function: Lights illuminate cargo and service compartment areas, such as maintenance and loading areas, during ground operations.

Exterior Lighting

• Purpose External lights illuminate the aircraft during flight and ground operations (runways and taxiways).
• Examples Lights include lights designed for takeoff, landing, and taxiing, plus navigation and anti-collision lights.

Emergency Lighting

• Purpose: Emergency lights illuminate escape routes during failures. They are located in interior and exterior areas.

Panel Light Dimmer Units

• Function: Provide variable AC power to panel lighting circuits.
• Power inputs & outputs: Input voltage is 115 volts AC; output is 0 to 5 volts AC.
• Location: Several dimmer units are located on the P7 panel.
• Maintenance: Dimmer units have one or two secondary circuit breakers for protection.
• Caution: Never operate dimmer units without a load as this may cause transformer burn out.

Indicator Lights

• Purpose: Indicator lights show system status.
• Relamping: Replace both lamps even if one fails.
• Removal procedure: Removal requires removal of the lens cap and following the correct procedures to avoid damaging the lens.

Switch Lights

• Function: Switch lights control inputs to the associated systems. Displays indicate switch position and/or system status using momentary and alternate-action switches.

Integral Panel Lights

• Description: Acrylic panel overlays with internally-mounted small incandescent bulbs illuminate panel lettering and schematics.

Master Dim and Test System

• Main component: The M886 module provides control for various light levels of indicator lights and aisle stand displays.
• Location: Positioned within the flight deck coat closet.
• Control switch: Located on the right panel lighting module (P5) with three settings for bright, dim, and test.

Flight Deck Access Lights

• Functionality: Provide illumination for entryways into the cockpit from the exterior, including access paths from main doors and from the equipment bay.
• Location: Mounted in specific locations, such as ceiling lights above stairwells, ceiling lights over doorways, and lights near the auxiliary equipment bay.
• Control: The lights are operated by switches near the entry points and in the cockpit.

Cargo Compartment Lights

• Description: A system of dome lights illuminates the cargo area, with additional lights near doorways for better visibility.
• Purpose: Ensure safe cargo handling and loading during ground operations.
• Power supply: The 115-volt AC ground handling bus powers these lights.

Exterior Lights (General)

• Types: Includes wing, landing, navigation, strobe anti-collision and logo lights, cargo door lights, and runway turnoff lights.

Exterior Lights (Wing Illumination Lights)

• Location/Mounting: Flush-mounted on the wing, above the fuselage and wing intersection.
• Lamp type: Sealed-beam incandescent lamps.
• Function: Illuminate wing leading edges and engine nacelles.

Exterior Lights (Landing Lights)

• Location/Mounting: Positioned in the forward wing leading edges.
• Lamp type: Halogen sealed-beam lamps.
• Function: Provide illumination of the runway during landing and takeoff.

Exterior Lights (Runway Turn Off Lights)

• Location/Mounting: Nose wheel light panel.
• Lamp type: Sealed-beam incandescent lamps.
• Function: Illuminate runway turnoff areas.

Exterior Lights (Navigation Lights)

• Location/Mounting: Wingtips and tail cone.
• Lamp type: Quartz halogen lamps.
• Purpose: Provide directional and positional cues.

Exterior Lights (Strobe Anti-Collision)

• Location/Mounting: Fuselage top and bottom, wingtips and tail cone.
• Lamp type: Xenon flashtubes.
• Function: High-intensity flashing lights to improve visibility..

Exterior Lights (Logo Lights)

• Location/Mounting: Upper horizontal stabilizer.
• Purpose: Illuminate airline insignia on the vertical fin.

Exterior Lights (Cargo Door Lights)

• Location/Mounting: Near the cargo doors on the fuselage.
• Purpose: Enhance visibility for cargo handling.

Emergency Lights

• Purpose: Provide illumination for cabin and exit routes during power outages.
• Components: Various light modules distributed in the cabin (ceiling, doors, overwings) with floor proximity lights, as well as, lighted EXIT signs.
• Power: Powered by 28-volt DC bus 4, using an emergency power source.