Abnormal Operations; Takeoff In Basic Mode - Honeywell PRIMUS 1000 Pilot's Manual

PRIMUSr1000 Integrated Avionics System
move from 115°to 0°. If the alignment is successful, the failure flags
are removed and the AHRS is valid. If not, the 5--second cycle starts
again.
If the heading card stops and does not step to an indication of 0° , the
initialization of the AHRS has not been completed correctly. The main
and auxiliary dc power to that AHRS must be removed by opening and
closing the circuit breakers, to restart the initialization.
NOTE: It is necessary that both breakers (primary and auxiliary
(AUX)) are pulled. Resetting each breaker individually does
not reset the AHRS.
In order to increase satisfactory ground initialization, the following must
be considered:
The aircraft must remain stationary on the ground until the attitude
D
and heading flags are pulled out of view. Normal passenger and
cargo loading, engine start, and engine run--up procedures can be
performed during the initialization. Wind buffeting is not limiting in
this respect. The aircraft cannot be towed, nor can it taxi during
AHRS initialization.
Two (2) minutes after power is connected to the dc buses, verify that
D
the attitude and heading flags are not displayed. If the timer has
stopped, the AHRS is not serviceable, and it should be reinitialized.
With the aircraft stationary, push and release the TEST button on
the AHRS controller. If the flags do not pull out of view after 10
seconds, reinitialize that AHRS.
Normal preflight taxi checks of pitch, roll heading, and rate--of--turn
D
must be made on each system.
If the aircraft is moved during AHRS initialization, both AHRS must
D
be reinitialized. This is done by pulling all four AHRS circuit
breakers. The four circuit breakers are then reset to their normal
position.

Abnormal Operations

TAKEOFF IN BASIC MODE

Takeoff with one AHRS in basic mode is not recommended. Verify that
both MADCs are operating.
NOTE: If a third attitude source is available, it can be used as the
primary data in place of the AHRS in the basic mode.
AHZ--800 Attitude and Heading Reference System (AHRS)
A--10
A28--1146--112--00