This is a look up the back end of the F-16 with the engine removed. The F-16 uses two different types of jet engines. Originally, Pratt & Whitney won the engine contract but couldn't keep up with production. They were flying brand new F-16s to the depot, then taking the engines out of them, to use in other F-16s. They had a ramp full of gutted F-16s, looking like this one. So they contracted with General Electric to take up the slack. So now there are two manufacturers for F-16 engines.