took off from GCRRappears L IRS was bad alligned, only CMD R workingPOS in FMC IRS L emptybut IRS R and GPS LR have dataso how do you make FMC/CMD switch to GPS (only) so CMD A works alsowhich seems to make sense that it should be able to(or what am I missing)?

once the aircraft is moving you cannot re-align an IRU

thats pretty clearwhat I want to know is how you make both CMD's (via FMC?) work after TO with 1 bad IRS(if at all)

Use the switch labeled IRS in the navigation section on the left of the overhead. Switch it to BOTH ON L or BOTH ON R as needed

Use the switch labeled IRS in the navigation section on the left of the overhead. Switch it to BOTH ON L or BOTH ON R as needed

aha, thxbtw, when I search "both on" in the PMDG-NGX-QRH.pdf I can find mentions like:"IRS TRANSFER switch. . . . . . .BOTH ON LDo not use either autopilot."that make me realize that CMDs need IRS working (GPS not enough)so back to the airport(actually I think I'll have to test if 2 CMDs work with 1 IRS aligned & 'BOTH ON' switched)?this still raises the question thoughif L IRS is not alligned, but R CMD workingthan I switch L IRS to OFFwhy the heck would then R CMD stop working??(this RealL?)

An invalid longitudinal acceleration from the ADIRU causes the autopilot to disengage.An invalid vertical acceleration from the ADIRU causes the autopilot to disengage.An invalid vertical speed from the ADIRU causes the autopilot to disengage.An invalid flight path acceleration from the ADIRU when in the dual mode causes the autopilot to disengage.The lateral acceleration from the ADIRU must be valid or the autopilot will disengage in certain modes.The magnetic track angle from the ADIRU must be valid or the autopilot will disengage in certain modes.If the IRS transfer switch is in the BOTH ON 1 or BOTH ON 2 position, the autopilot will disengage and cannot be reengaged.