There's 2 of them.

Boy of boy, was the end of WWII a real watershed for jet airplane design. Not only were the planes being developed during the insanely high stress final years of the war, but they were test flying then one week and tooling the factory the next to start production. After the war, when the first passenger jet airplanes started showing up at airports, they were usually parked far away from the terminal and metal pans placed beneath the engines in case the "self igniting" jet fuel should leak out or spill.

No doubt German engineers had it down when it came to the jet powered aircraft. C'mon, the were the first to use swept wings, molded high altitude canopies, even ejection seats. (You did have to get out of them occasionally). Sadly, many test pilots didn't. The damn things were just too fast, too powerful and had only a few things sorted out by the time they were tested. Often, the fact they had a pointy bit in the front, an engine out the back and 2 or more wings, that was enough to give them a whirl.

Case in point, the Horten Ho 229. Production models were called the Gotha Go 229 and were built by Gothaer Waggonfabrik, originally a manufacturer of train cars. Hmmm, good choice. Whilst building tram cars they also dabbled in aircraft manufacturing as the Nazi government ignored the Treaty of Versailles and armed the country to the teeth. One of their early products to actually see service was something called the Gotha Go 242, described as an "assault glider". The only assaulting thing it really did was drop off 2 dozen really angry German troops. They had, after all, to travel in the damn thing. It never actually assaulted anything.

Back to the Go or Ho 229. It was designed by Walter and Reimar Horten. The design was a flying wing type powered by twin jet engines. The Horten brothers were not university trained but had been avid glider builders for years (between the wars it was the only things with wings you could get away with building in Germany). The flying wing was something they played around with alot and knew the advantages when it came to powering the aircraft as a wing only design limits drag because there is no fuselage. Less drag means more range, larger payload and faster speeds. A wing and a couple of engines is really only half an airplane. This plane, could have however actually met the 1000, 1000, 1000 design objective dreamed about by Goring. He wanted an aircraft that could go a 1000km, carry 1000kg of bombs and go 1000km an hour.

The test version was a bizarre combination of wood (plywood actually, now that's safe) and welded steel core frame. Unpowered gliders were first tested in the spring of 1944 with unmanned powered tests that winter.