Yep, the radio-based navaids would be toast.
So, here's to pilotage!
Got my plotter and a watch and a chart.
> radio-based navaids would be toast <
No disagreement when we're talking about IC-based equipment. I do think, however, that tube-using transmitters and receivers have greater survivability in the face of an EMP. So let's not throw away all those antique radios in the attic. And stock up on your supply of 6Y6's, 807's, 5U4G's and the like!
(Just be sure you replace those big capacitors in the power supplies before you plug anything "antique" into the mains. Old capacitors often leak and lose most of their oil over the years.)