IRS Mode Selector/PSEU Flashcards
IRS MODE SELECTORS
Left ADIRU normal power source
115v AC sby bus
IRS MODE SELECTORS
Left ADIRU alternate power source/duration
28vdc from switched hot battery bus.
Powered until voltage drops below 18v
IRS MODE SELECTORS
Right ADIRU normal power source
115vac #2 transfer bus
IRS MODE SELECTORS
Right ADIRU standby power source/duration
28vdc switched hot battery bus
Powered for 5 mins
IRS MODE SELECTORS
ADIRU power source required for startup
Both AC and DC
IRS MODE SELECTORS
NAV
Alignment between which latitudes
78° 15 minutes north or south
IRS MODE SELECTORS
ATT mode description
- 2 second delay prevents accidental selection
- provides gyro data- pitch, roll and compass. Heading processes and must be entered.
- keep aircraft straight and level for 30 secs for calibration
- IRS position and ground speed information lost
- cannot use FMC for nav if all IRSs are in ATT
IRS MODE SELECTORS
ALIGN light (white) illuminated flashing
Alignment cannot be completed due one of the following:
- aircraft movement- will start again once movement stops
- significant differences between previous and entered positions
- needs a present position
IRS MODE SELECTORS
GPS light illuminates
Illuminates on recall for one GPS hardware failure. Still have signal
Illuminates by itself for dual GPS failure
IRS MODE SELECTORS
Time difference for alignment at min and max latitudes
Equator- 5min
78.25°- 17min
PSEU
Stands for…
Proximity switch electronic unit
PSEU
Components controlled by PSEU
Monitors 2 systems (PRI & ALTN) for internal and external faults
Systems/components:
- takeoff config warnings
- landing gear position indication/warnings
- landing gear transfer valve
- airstairs conrol/warning
- SPEEDBRAKES EXTENDED light
- air/ground relays
- door warning
PSEU
Light inhibited
- thrust lever advanced for takeoff
- in flight
- 30 secs after landing
PSEU
Illuminates when…
No dispatch fault stored in PSEU memory
Air/ground system in override mode
