Mxsmanic wrote:
Nomen Nescio writes:

The category that has wings and goes up in the sky.

You mean like a 747-400? It has two GPS receivers, three IRUs, two VORs and
two ADFs. One rarely falls back upon the magnetic compass.

Once again you decide to generalize the entire realm of aviation
by your simplistic study of the simulation of one aircraft.

There are a great number of transport category aircraft with
neither INS nor GPS.