Light

         

TTP Cessna 172	B1	L3	ATA33	Light
	B2	L3

  

Single white neon tube  under glareshield provides overall lighting for the instrument panel.

Glareshield dimming control is mounted below and to the left of the throttle.

The flight instruments individually light by a replaceable light bar assembly. The light bar assembly is at the top of the instrument. Engine instruments are individually lighted by replaceable light bulb assemblies.
Both flight and engine instruments are operated by a dimming control unit.

Radio lighting consists of internally lighted radios, a dimming module and a dimmer control.

Map light is installed on the lower surface of the pilot’s control wheel.

Navigation lights - The airplane is equipped with both fixed intensity navigation lights and pulsing strobe lights.

Navigation lights are located on the left wing tip, right wing tip and tailcone. The navigation lights in the wing tip are co-located with the strobe assemblies, and the light in the tailcone is located in its own housing.

Bulbs for all three navigation lights are clear. The lens assembly on the right wing tip is colored green, the lens assembly on the left wing tip is colored red, and the lens assembly on the tailcone is clear.

Navigation lights are activated by placing the switch/circuit breaker in the NAV position. This position supplies power concurrently to all three lights.

Strobe lights are co-located with navigation lights in the wing tip housing.strobe and lens assembly are both clear. The strobes are activated by placing the switch/circuit breaker in the STROBES position. This position supplies power to the right and left power supply, providing pulsed energy to fire the strobes.

Beacon - The vertical fin beacon is located on top of the vertical fin cap assembly and provides a flashing red light to aid in airplane recognition.

Put the LIGHTS BCN/OFF switch to the BCN position to start the flashing beacon. This position supplies power to the light. Internal circuitry makes the light flash on and off at approximately 50 cycles per minute.

             The landing and taxi lights are installed on the left wing leading edge between WS 100.00 and WS 118.00. The landing and taxi lights are controlled by two switches on the circuit panel assembly. The landing light is operated by the landing light switch and the taxi light is operated by the taxi light switch.

            Some a/P have a high-intensity discharge (HID) landing and taxi light installed. The landing and taxi lights have an igniter installed on the back side of each light.

 A ballast is necessary for the operation of the HID bulbs. The ballast for the landing light HID bulb (inboard bulb) is installed on a bracket that is attached to a wing leading-edge rib inboard of the bulb. The ballast for the taxi light HID bulb (outboard bulb) is installed on a bracket that is attached to a wing leading-edge rib outboard of the bulb. The wiring is almost the same as the incandescent bulb installation, but there is one more cable necessary to connect the ballast to the HID bulbs. The landing and taxi light switches, and the landing and taxi light circuit breakers for the HID lighting system are the same as those for the incandescent lighting system.
 Courtesy light - Each wing is equipped with a courtesy light located near the strut/wing intersection. The left wing light, the right right light and the rear dome light are connected in parallel on a single circuit. Pressing the overhead light switch supplies power to all three lights.Pressing the overhead light switch again removes power from all three lights.

PTP Cessna 172	B1	LOC	FOT	SGH		MEL
	B2	LOC	FOT	SGH	R/I	MEL

331001 Instrument and Cabin Lights - Check operation, condition of lens, and security of attachment.
334001 Navigation, Beacon, Strobe, and Landing Lights - Check operation, condition of lens, and security of attachment.