T-45C TS, ADV & IUT ENG-20
Flight Instruments Malfunctions
2. Verifications
a. If below 5000 ft AGL, radar altimeter altitude plus known terrain
elevation disagrees with standby altimeter
b. Cross-check indicator in other cockpit or other aircraft
c.
Erroneous response to VSI
d. Cabin pressure altitude disagrees below 5000 ft MSL or if cabin
is unpressurized
3. Effects on flight safety
a. Unreliable altitude readout
b. Reduced approach capabilities
WARNING: On all descents, it’s good headwork to cross-
check other instruments such as the radar and cabin
altimeters.
C. Standby vertical speed indicator (VSI) failure
1. Indication: pointer freezes or fluctuates (appearing unreliable)
2. Verifications
a. Cross-check with the following:
(1) Standby attitude indicators
(2) Standby airspeed indicator
(3) Standby altimeter
b. Cross-check indicator in other cockpit and/or with other aircraft
3. Effects on flight safety
a. Loss of rate of climb/descent information
b. Instrument approach capability downgraded
D. Pitot tube damage/icing
1. Indications: erroneous readings from all airflow and pressure
instruments (standby airspeed indicator, standby VSI, standby
altimeter, SADS and OBOGS)
2. Verifications
Original (9-98)
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