[Scan-DC] FM Radio Question

[William D. Rossiter III]

I notice that sometimes at night when I am listening to my FM radio (88-108
MHz), very short interuptions occur during the regular programing, and in
their place I hear commercial airplane pilots (at least thats what I think I
am hearing because I always hear the words "Delta, USAir, American West").
For me, this always happens during the night and mostly happens when my
radio is tuned to 99.1 WHFS.

1.  Does anybody know what is happening?  (My theory is that it has
something to do with planes flying over my house, and their cockpit radios
overload my stereo.  I also think it could have something to do with the
"harmonics" phenomona.)

2.  Has this happened to anyone else?

Thanks a lot,
Bill