Airplane Flight Manual Supplement

Hawker Beechcraft C90A and C90GT King Air 190-00682-02 Rev. C
Page 34 of 95
NOTE
When comparing indicated altitude to GPS altitude, deviations from standard temperature or
pressure can cause indicated altitude to deviate from GPS altitude. These errors are largest at
high altitude. Below 10,000 feet with the correct local altimeter setting set, GPS altitude will
usually be within 600 feet or better of the correct indicated altitude. Use the following guidelines
to help estimate correct altitude from non-standard conditions:
• Temperatures WARMER than standard can cause GPS altitude to read HIGHER than indicated
altitude.
• Pressures LOWER than standard can cause GPS altitude to read HIGHER than indicated
altitude.
¾ IF ABLE TO IDENTIFY ACCURATE ALTITUDE SOURCE
6. Use SENSOR softkey to select most accurate ADC on both PFD’s
¾ IF UNABLE TO IDENTIFY ACCURATE ALTITUDE SOURCE
6. Avoid IFR conditions if possible; consider diversion to visual conditions and LAND AS SOON AS
PRACTICAL.
7. Maintain altitudes based on LOWEST indicated altitude.
8. ATC – Advise of inability to verify correct altitude
9. If unable to descend into visual conditions, plan an ILS, LPV, or RNAV (GPS) LNAV/VNAV
approach with course intercept well outside the Final Approach Fix (FAF).
10. Once glideslope or glidepath is captured, determine most accurate altitude source when crossing
FAF.
11. Reference ILS Decision Altitude or GPS based approach Minimum Descent Altitude to most
accurate altimeter based on FAF crossing.
TAWS ALERTS ARE BASED ON GPS ALTITUDE AND POSITION INFORMATION. TAWS
WARNINGS AND CAUTIONS ARE INDEPENDENT OF ADC DATA. IF A TAWS WARNING
OR CAUTION IS RECEIVED, CONSIDER IT ACCURATE AND TAKE IMMEDIATE
AVOIDANCE ACTION.
WARNING