Hiller OH-23 Raven
The Hiller UH-12 was a development of the Hiller Model 360 from 1948. It was equipped with a Franklin 6V4-178-B33 engine rated 175 hp. This type made the first transcontinental commercial helicopter flight.
With another engine and new rotor blades the UH-12 was bought by the US Army under the designation UH-12A . Its military designation was H-23 Raven. The US Navy also used the type with Naval designation HTE-1, mainly as a trainer.
- The H-23B:
- was equipped with a more powerful Franklin 6V4-200-C33 engine rated 200-210 hp. 216 examples of this type were used by the US Army as H-23B for training purposes and another 237 examples were used for general purposes.
- The UH-12B:
- This type could have skids or floats. The US Navy ordered a series under the designation HTE-2 equipped with wheels.
- The UH-12C:
- was released in 1955 and had the same engine, but full metal rotor blades and Bell 47 like canopy. 156 examples were delivered to the US Army under the designation H-23C.
- The OH-12D:
- was a fully military version was released in 1956, 483 of this type were used by the US Army. The engine was a more powerful Lycoming VO-540 rated 320 hp and also the transmission was modified and improved.
- The UH-12E:
- the best known version was equipped with a more powerful engine. The US Army used this type under the designation OH-23G to replace all Hillers OH-23D.
- The UH-12E:
- In 1960 a four seat version was released as Model E4, with an enlarged cabin and revised stabilizer. The US Army used 23 of this type under the designation OH-23F.
|Length with rotor||8,8 m||Height:||7,7 m|
|Rotor diameter||2,5 m||Tail Rotor diameter||- m2|
|Empty weight:||457 kg||Full weight:||839 kg|
|Max. speed:||153 km/hr||Cruising speed:||135 km/hr|
|Range:||330 km||Service ceiling:||4025 m|
|Engine:||One Franklin 0-335-6 rated 250 hp|
|Crew:||Two men: one aviator plus one observer|