AFFECTED PRODUCTS AND AIRCRAFT
Garmin G900X Systems installed on any aircraft and Garmin G1000 Systems installed on the following aircraft with GDU 1XXX software versions prior to V8.20:
- Cessna 350/400
- Piper PA32
- Quest Kodiak 100
- Hawker Beechcraft G36 Bonanza
IMMEDIATE ACTION REQUIRED
The pilot should select and use NAUTICAL (NM and KTS) Distance and Speed units instead of selecting and using METRIC Distance and Speed units (KM and KPH).
DESCRIPTION OF ISSUE
Affected aircraft use a Calculated Fuel Range Field (Figure 1) that works correctly only when the Distance/Speed Display Unit Field on the AUX – System Setup Page is set to NAUTICAL (NM, KT).
When the Distance/Speed setting on the AUX System Setup Page is changed to METRIC (KM, KPH), the Calculated Fuel Range Field on the Engine System Display is inaccurate. This may cause the pilot to mistakenly believe he can fly farther than is possible on the remaining fuel.
RESOLUTION
GDU software V8.20 or later incorporates a change correcting the issue. Until GDU software V8.20 or later is installed, the pilot should select NAUTICAL (NM, KT) Display Units for Distance/Speed on the AUX System Setup Page. Instructions on changing the Distance/Speed Units are in the Pilot’s Guide and Cockpit Reference Guide for the aircraft listed in this Service Alert.