97-12 LRU Installation – GDC 74H Air Data Computer (continued)
D. Installation
1. Turn battery & avionics switches off and pull out EFIS (5 amp) circuit breaker on
circuit breaker panel.
2. Place GDC 74H air data computer on F950-2 support assembly and install screws.
Verify security.
3. Remove plugs from fittings and connect pitot and static tube fittings to computer.
Verify security. Perform pitot and static system leak checks per § 95-10.
4. Connect airframe harness to computer at connectors.
5. Push in EFIS circuit breaker (5 amp) on circuit breaker panel. Turn battery &
avionics switches on.
6. Perform appropriate functional checks per Garmin G500H Instructions for
Continued Airworthiness. Turn battery & avionics switches off.
7. Install F748-1 cover assembly and hinge left seat back.
E. Scheduled Maintenance and Inspections
Refer to Garmin G500H EFIS Maintenance Manual, Section 5 Periodic Maintenance.
NOTE
All factory-installed Garmin units are “on condition” and do not
require scheduled periodic maintenance. Units feature a BIT
(Built-In Test) function during each initial power-up that will
detect internal failure(s) and alert pilot.
NOTE
Refer to § 97-60 for avionics software information.
F. Special Maintenance and Inspections
1. Turn battery & avionics switches off. Open circuit breaker panel, hinge left seat
forward, and remove F748-1 cover assembly.
2. Inspect condition of and verify no obvious damage to Garmin GDC 74H Air Data
Computer, pitot-static tubes, circuit breaker, and wiring. Verify no loose, chafed, or
broken wires or terminals. Verify no evidence of arcing. Verify equipment security.
3. Secure circuit breaker panel. Perform ground checks per Part D steps 5 thru 7.
Page 97.2 Chapter 97 Avionics APR 2019
To Next Page
