The FE2 was a British two seater biplane from the first world war, the last successful 'pusher' genuinely-propeller aircraft, before the switch to universal 'puller' or 'tractor' airscrews mounted in front.
FE2s pretty much dominated as fighters from about 1916-17; before being overtaken by a new generation of faster and deadlier German machines.
The pusher planes were used mainly because they allowed a machine gun to fire forward - without shooting the airscrew to pieces (a problem that was solved during the course of the war).
The FE2s had a forward-facing Lewis gun operated by the observer, but soon added a rear-facing gun - shooting backwards over the top of the wing. This meant that, helped by a skilled pilot, the coverage was more complete than for any other craft of the era.
And to operate and reload this rear-facing Lewis gun; the observers had to stand-up, unsecured (and, of course, without a parachute)!
How cool is that?