Oleg, you'll be my hero forever if you can do this:

[nearmiss]

Are you saying pilots were flying and listening to music and other radio broadcasts (non-military communication)?

I realize the 1940s were big years for radio broadcasting, but I've never read any accounts of pilots listening to entertainment radio while on missions.

AM = is the method of shortwave broadcasting.

Everyone back then had shortwave receivers, but they did require very careful tuning, which would have been difficult to do while flying.

Maybe in a bomber where you had a radioman it was possible. I don't recall any accounts of pilots tuning in to entertainment radio on missions.

It would have been possible in some instances to receive entertainment radio while flying, radio waves were filling the air during WW2.

[Viikate]

Normal commercial AM radio station can be used for navigation just like non-directional beacons. But of course the pilots didn't listen Glenn Miller all the time as if they would have iPods.

For example mid-late war German single engine planes had mostly FUG 16Z radios. Z meaning zielflug (homing). There a ZF-FT switch to toggle between two modes. Zielflug or Funktelegraphie. So you either can tune to NDB/radio station frequency and us it for homing OR you can talk to your wingman or ground control. So obviously Hans is not listening Lili Marleen all the time.

Bombers normally have several radios (mediumwave, shortwave, etc.) Check Ju-88 or Bf-110 for example. They could have kept one channel open for communication between planes and tune another receiver to AM radio station and route the music through intercoms so that all members of crew can hear it. To relieve battle stress and uplift moods.