Any idea what the discrepancy in position was in NMs?
If it is more than (I think) 40-ish NMs the TOGA update won't take properly and the IR inputs won't update your position quickly enough to be useful.
You are in good (not to say, exalted) company. One large carrier did this, and, since the only remedial action to regain proper map function was to land and re-initialise the inertials, they continued on raw data!! - Luckily they had a heavy crew, 'cos it was a loooooooong sector! Another example from the long-haul world was down to the company operating from HR
and LGW - yes, you've guessed it - and the distance is in the problem area.
Murphy does it again
