It's beyond stupid - it was beyond stupid when it was a knee-jerk reaction from the government, and it would go well beyond stupid if Delta was telling its crews to selectively turn off the map " for security purposes". Of course, leave it to Delta and United to think up more ways to kiss the TSA's behind.

You don't even need a GPS - an iPhone with a compass (or heck, just a compass), and a simple formula of 'distance=speedxtime', which can be flipped around to solve the missing variable. It's not hard to look up the average ground speed for your flight (and even view historical routes), then you can solve for time and distance, and use the compass to give a decent estimation of your position and remaining time/route of flight.

It makes me feel so much safer when the government (and some airlines) assume all terrorists are as stupid as Reid and the Undiepants Bomber.