History

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.

Versies

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.

 

Technical information Hiller UH-23B
Dimensions:
Length with rotor 8,8 m Height: 7,7 m
Rotor diameter 2,5 m Tail Rotor diameter - m2
Weights:
Empty weight: 457 kg Full weight: 839 kg
Performances:
Max. speed: 153 km/hr Cruising speed: 135 km/hr
Range: 330 km Service ceiling: 4025 m
Miscellaneous:
Engine: One Franklin 0-335-6 rated 250 hp
Crew: Two men: one aviator plus one observer