POPOV35 and 36 are two pilots that identified a convoy on the ground. Hotel Manilla is the on the ground giving orders to the pilots to shoot the convoy. The one of the pilots sees that there are orange panels on either side of the convoy indicating that the convoy may be a group of "friendlies" i.e. allies. The British ally's missiles are usually orange. The one pilot repeatedly asks for Hotel Manilla to confirm that there are no friendlies on the ground and Hotel Manilla repeatedly confirms that there are none.
The pilots bomb the convoy and immediately afterwards "Lightening" informs them that there are friendlies on the ground. (I have no idea what or who "Lightening" is.) Hotel Manilla then states that there were in fact friendlies down there.
Part 2 of the tape, pretty much of the pilots saying "fuck," "Goddamn it," and "I think I'm going to be sick" and some pretty heavy breathing.
It's all really disturbing.