Dual FMGS& dual RMP loss-A320

[Mach trim]

What if you are flying along in cruise and you lose both FMGS and RMPs ?

What have you got left for communications and navigation ?

Yeah you Aviate Navigate Comm., any suggestions ?

Your IRS'S are working fine. So you have autotuning .

Thanks

[fantom]

I respectfully refer you to the FCOMs, Sir or Madam.

[Mach trim]

In the dual FMGS loss following prcoedures,AP/FD'S off, ATHR off.

Then you try a reset from FCOM 4 and no joy.

What gets me is the part where you use STBY NAV key on the RMP's ?

You cant use these NAV keys as you have no RMP's


fantom,The FCOM's, sir. Do not have anything about losing both RMP's combined with a dual FMGS or just losing both RMP's.

Unlikely, yes.

Yeah if you lost only your RMP's then you could use the RAD NAV page.

[Clandestino]

I got my FCOM only a week ago, but MHO is that in this extremelly unlikely event (if these are independent faults and not caused by total electric failure), you'll be out of any NAV/COM options but the plane will still be flying (surprise,surprise). So it's time to do DR navigation to place where you can do visual descent and app to runway long enough.

Also I think IRS are not enough for autotuning, whole FMGC neds to be operative, but I might be wrong, I'm new here.

[fantom]

Mach,

You said: "your IRSs are working fine. So you have autotuning" .

Not so. The IRSs help the FMGCs provide autotuning. The IRSs alone cannot provide it.

RMP 1 and 2 will only (mostly only) be lost in case of DC Bus failure (in which case you use RPM 3). You are never alone.

Stby Nav is available, even in Emerg Elec Config.

It is not easy reading the books; when you see the hardware, it will be plain to see.

Don't be scared; it's fine.

[gearpins]

With FMGC 1+2 gone the a/c is like any normal conventional pre eighties jet.no ND, no A/P,A/THR, flight guidance and flight management lost.
added to this if you loose RMP1&2,whats left is
stby instuments and a clock:\
now we fly like in the 60s.
I would use my FD in track mode to take care of drift
use the paper flight plan time log for track change (fcu is still working)
communicate my status to all and sundry neg RVSM etc...
once within radar coverage request a talk down or VMC visual circuit
and defenitely demand a lot of beer that night:)

[gearpins]

and if we dont have FDs...............well well well....that would be some thing. :\

[Clandestino]

I thought of RMP3 too, but it seems it's optional (not that I've seen a bus without it) and it can't be used for NAV tunning.