Göppingen Gö 9
Description
Role	Experimental
Crew	one, pilot
Dimensions
Length	6.80m	22' 4"
Wingspan	7.20m	23' 8"
Height
Wing area
Weights
Empty
Loaded	720 kg	1,587 lb
Powerplant
Engine	1x Hirth HM 60
Power	60kW	80 hp
Performance
Maximum speed	220km/h	137 mph
Range
Service ceiling
Rate of Climb
Armament
None

The Göppingen Gö 9 was a research aircraft built to investigate the practicalities of powering a plane using a pusher propeller located far from the engine and turned by a long driveshaft.

In 1937, Claudius Dornier observed that adding extra engines and propellers to an aircraft in an attempt to increase speed would also attract a penalty of greater drag. He reasoned that this penalty could be minimised by mounting a second propeller at the rear of an aircraft. In order to prevent tail-heaviness, however, the engine would need to be mounted far ahead of it. Dornier patented this idea and commissioned a test plane to evaluated it.

The aircraft was designed by Dr Ulrich Hüter as a scaled-down version of the Dornier Do 17 and built by Schempp-Hirth. Power was supplied by a Hirth HM 60 mounted within the fuselage near the wings. Other than the engine installation, the only other unusual feature of the aircraft was its tail, which included a large ventral fin. This fin incorporated a small wheel that assisted in keeping the rear-mounted propeller away from the ground during take-off and landing.

Flight tests began in early 1940, initially towed aloft, but later taking off under its own power. The design validated Dornier's ideas, and he went ahead with his original plan to build a high-performance aircraft with propellers at the front and rear, producing the Dornier Do 335. The eventual fate of the Gö 9 is not known.