IRS

Question 1

The left IRS is on which bus?

Answer 1

AC Standby bus

Question 2

The right IRS is on which bus?

Answer 2

AC transfer bus

Question 3

IRS display shows what in the two windows on the system test?

Answer 3

All 8’s

Question 4

Moving the DSPL SEL to “test” does what?

Answer 4

Illuminates all the lights on the ISDU (IRS Display Unit)

Question 5

Moving the DSPL SEL in TK/GS means what?

Answer 5

Left window displays true track(course)
Right window ground speed

Question 6

Moving the DSPL SEL to wind?

Answer 6

Left: true direction
Right: velocity

Question 7

Moving the DSPL SEL to PPOS?

Answer 7

Shows present Lat/Long

Question 8

Moving the DSPL SEL to HDG/STS?

Answer 8

Left: true heading
Right: displays any applicable maintenance status codes
Shows time until alignment, if alignment longer than 15 mins, shows 15 until 14 mins remain

Question 9

The SYS DSPL knob has what positions and does what?

Answer 9

Two positions: L and R
Selects which IRS system drives the display

Question 10

IRS: GPS light illuminated for what two reasons?

Answer 10

Dual gps channel failure, light illuminates
Single gps channel failure, light illuminates when either system annunciator panel RECALL pressed

Question 11

The ALIGN light illuminated white means what steady and flashing and extinguished?

Answer 11

steady - the related IRS is aligning or is in shutdown cycle

Flashing - the alignment could not be completed:
1. Significant difference between previous and entered positions, or
2. An unreasonable present position entry
3. No present position entry
4. Aircraft movement

Extinguished - IRS not in align mode
- mode selector in NAV, alignment complete, all IRS info available
- mode selector in ATT, attitude info available, heading info available following entry of initial MaG heading