This is just a curiosity question on my part.
Part of my job is that I sometimes review AFM revisions for accuracy in my area of expertise (engines). While it's not exactly applicable to me, I've often noticed notes on the Inertial Reference Systems that the IRS readings are 'valid' between 82 degrees north and south latitudes.
My question is,: what do you do if your flight path would take you higher than 82 degrees? Do you need to re-plan to a lower latitudes, or do you use other systems (e.g. GPS) when in the polar areas above 82 degrees?
Like I said, just curious
