FM radio Interference
While hearing FM radio at a at frequency of 106.4MHZ I can hear the
  cockpit commands/voices daily when these IAF flights cross by.


The VHF airband (in most countries as far as I know) uses frequencies between 108 and 137 MHz and although these are AM modulated they are nicely positioned in the spectrum to be picked up by a standard FM radio that has an IF of 10.7 MHz. This picture may help: -



So, you have your FM band and you have a "wanted" channel that you need to convert to an intermediate frequency of 10.7 MHz. You position your local oscillator so that it is 10.7 MHz higher than the wanted channel and mix-down the wanted signal to 10.7 MHz for band-pass filtering and subsequently demodulation. However, you could also mix down an unwanted channel that is 10.7 MHz higher than your local oscillator.

So, 106.4 MHz plus an IF offset of 10.7 MHz is 117.1 MHz - this would be your local oscillator frequency and an unwanted image that is 10.7 MHz higher (at 127.8 MHz) could also produce an IF of 10.7 MHz. Given that FM demodulators can also amplitude demodulate a weak AM signal this is a possible culprit.

Back when I was a teenager I could pick up the cops on my FM receiver although they were using a frequency and modulation that I should not theoretically be able to receive.


  I cant hear the same interference in mobile FM.


What frequency(ies) does it use?