For the sake of discussion: Now suppose IFR conditions and a hypothetical directed RF attack vector which spoofs instrument nav/pos data...I'm thinking GPS, VOR, radar altimeter.
I'm not a pilot, but if I was "in the soup" when this happens, first I'd try radioing the ATC and asking Victor for a Vector out of it. Then fly that vector straight & level. No radio, then it's old-fashioned map, compass, and dead reckoning. A 757 has a lot of range, so you should be fine.
My father was a navigator in B-17s, and used celestial navigation. I suppose they don't teach pilots that anymore.
They do, but you need to be able to see your references to be able to do that.
Edit: also some aircraft are going totally glass. I've seen some homebuilts and super cubs without steam gauges completely, and it's just a matter of time until Cessna, Boeing, Airbus, etc eliminate them.
That's what I said upthread a couple of posts. The penlight thing was in response to someone saying what to do if it is too dark to read the instruments.