Flying on standby gages must remind you of your Hawkeye days
Anyways.......to answer the question at hand...
On that INS, there's usually 2 of em on, say, a 737/MD-88, but 3 on a 757/777 type jet. System 1 to AFCS 1, and so on....On Capt's leg, they usually use AFCS 1, F/O's, it's AFCS 2...so the INS units are both aligned, but one autopilot is used for flight at least...I know on most newer jets, excluding the MD
-80 series, all autopilots have to be engaged for APP mode.
If you move those selector knobs out of "NAV" while in the air, forget it, you've lost your data. You can't fully realign in the air really, so it's back to charts and VOR's for you
Thankfull,y the knobs have to be pulled OUT of their detents before you can move them from NAV...so the crew's noggins won't kill the system when they get up for a lav break
At the gate, when you're doing your POS
INIT page on the FMS, you enter the airport and gate, but before you're allowed to enter that as the IRS position, you have to go to a quick realign on the overhead, rotating the knobs to ALN, then back to NAV..this elminates "drift errors" and any drift from the last flight. Then you're allowed to tell the FMS where you are. On the first flight of the day, it takes considerably longer to align them from OFF....10 mins IIRC? Remember this has to be done at the gate, as you can't move the aircraft at all during the alignment. That's why airborne align doesn't work.
I'm speaking from the Delta MD
-88 PRM on most of this, I know things may be a little diff on the newer generation systems, ex 757->738. I'll crack it open if I mucked it up and somehow didn't tell you correctly the first time
"The cockpit, what is it?" "It's the little room in the front of the plane where the pilot sits, but that's not importan