Airplane Flight Manual Supplement

G500 PFD/MFD System 190-01102-00 Rev. 5
Instructions for Continued Airworthiness Page 7 of 13
2.5.9 Mid Continent Instruments Attitude Indicator Models 4300-4( ), or 4200-( ) with MD420
If a Mid Continent Instruments Attitude Indicator is installed as part of the G500 AML STC, within the
preceding 12 calendar months each battery pack must be tested by one of the following means:
1. Manual:
a. Disconnect each battery pack from the Attitude Indicator or Battery Module.
b. Ensure each battery pack is completely charged (per Section 2.4) and at or near room
temperature (20-25°C).
c. Connect each battery to a load of 90 ohms (rated for 10 watts) for 60 minutes while
monitoring the battery voltage level.
i. If the battery voltage is at or above 15.0 volts while under load at the end of the
60 minute test, the battery may be recharged immediately in accordance with
Section 2.4 and re-installed in the aircraft.
ii. If the battery voltage is below 15.0 volts while under load at the end of the 60
minute test the battery must be replaced.
2. Automatic:
a. Use the Mid Continent Instruments Battery Charger/Tester P/N 36029 to test the battery.
i. If the time required for discharge is 60 minutes or greater, the battery may be
recharged immediately in accordance with Section 2.4 and re-installed in the
aircraft.
ii. If the time required for discharge is less than 60 minutes, the battery must be
replaced.
****WARNING****
The battery may be permanently damaged if it is left in a discharged state.
Recharge a discharged battery as soon as possible and
maintain with a float charge for maximum battery life.
Within the preceding 12 calendar months, proper operation of the attitude instrument must be verified
with the following procedure:
1. Apply aircraft power to the unit and verify that the invalid flag is removed from view and the
STBY PWR indicator is not illuminated.
2. Remove aircraft power from the unit and verify that the invalid flag is not visible and the STBY
PWR indicator is flashing.
3. Press the STBY PWR button and verify that the invalid flag is not visible and the STBY PWR
indicator is not flashing.
4. Press the STBY PWR button a second time and verify that the invalid flag is displayed.
Otherwise maintenance of the Mid Continent Instruments attitude indicator is ‘on condition’ only.