YH-32 Hornet

Infobox Aircraft
name= YH-32 Hornet


caption=Hiller YH-32 Hornet in museum display
type=Experimental helicopter
manufacturer=Hiller Aircraft
designer=
first flight=1950
introduced=1954
retired=
status=
primary user=United States Army
more users=United States Navy
produced=
number built=18
unit cost=
variants with their own articles=

The Hiller YH-32 Hornet (company designation HJ-1) was an American ultralight helicopter built by Hiller Aircraft in the early 1950s. It was a small and unique design because it was powered by two Hiller 8RJ2B ramjet engines mounted on the rotor blade tips. Versions of the HJ-1 Hornet were built for the United States Army and the United States Navy in the early 1950s.

The Hiller Museum identifies the YH-32A, named the "Sally Rand", as the first helicopter gunship.

Design and development

The Hiller HJ-1 Hornet was an early attempt to build a jet powered helicopter. Its ramjet tipped rotor propels the rotor and the aircraft. Unlike a conventional helicopter, this mechanically simple design avoids the need for a tail rotor.

Unfortunately, the tip speeds on helicopters are subsonic, and ramjets are inefficient at subsonic speeds due to low compression ratio of the inlets. Therefore, the Hornet suffered from poor fuel consumption and range. Also, the vehicle suffered from low translational speeds and the ramjet tips were extremely noisy. In the event of power loss, autorotation was found to be difficult due to the drag from the ramjet nacelles. [cite web | title=Tip-Jet Rotor Helicopters | url=http://www.aerospaceweb.org/question/helicopters/q0141.shtml | publisher=Aerospaceweb.org | date=2003-09-14 | accessdate=2008-06-23]

The vehicle exhibited powerful lifting capacity, and there was some hope for military uses, but the high noise, poor range, and high night-time visibility of the ramjet flames failed to attract sales.

Operational service

The HJ-1 was evaluated by the United States Army as the YH-32, and the United States Navy as the XHOE-1. In 1957 two YH-32s were modified as the YH-32A for trials as an armed helicopter, all the fibreglass cockpit fairing were removed and the tail was modified. The test were successful in proving the viability of a helicopter as a weapons platform, but due to marginal performance no further conversions or orders were placed.

Variants

;HJ-1:Company designation, one prototype.;YH-32:United States Army, Similar to HJ.1 with two small v-shaped stabilisers, 14 built.;YH-32A:Two YH-32s modified for trials as an armed helicopter.;XHOE-1:Three HJ-1s for evaluation by the United States Navy in 1951.

Aircraft on display

*HOE-1 (HJ-1) is on display at the Hiller Aviation Museum in San Carlos, California
*HOE-1 (XH06-1) is on display at the Udvar-Hazy Center of the National Air and Space Museum in Chantilly, Virginia
*HOE-1 (YH-32) s/n 55-4965 "Sally Rand" is on display at the US Army Aviation Museum at Fort Rucker in Ozark, Alabama
*HOE-1 (YH-32) s/n 55-4969 is on display at the Museum of Flight in Everett, Washington
*HOK-1 s/n 139990 is on display at the Carolinas Aviation Museum in Charlotte, North Carolina
*YH-32 Hornet is on display at the Hiller Avaiation Museum in San Carlos, California
*YH-32 Hornet is on display at Classic Rotors in Ramona, California

pecifications (YH-32)

aircraft specifications

plane or copter?= copter
jet or prop?= jet
crew=two pilots
length main=
length alt=
span main= 23 ft
span alt= 6.9 m
height main=7 ft 10 in
height alt=2.4 m
area main= 402 ft²
area alt=37.4 m²
empty weight main=544 lb
empty weight alt=247 kg
loaded weight main=1,080 lb
loaded weight alt=490 kg
max takeoff weight main=
max takeoff weight alt=
engine (jet)= Hiller 8RJ2B
type of jet= ramjets
number of jets= 2
thrust main= 40 lbf
thrust alt= 178 N
max speed main=
max speed alt=
range main=28 miles
range alt= 52 km
ceiling main= 6,900 ft
ceiling alt= 2,100 m
climb rate main=700 ft/min
climb rate alt=213 m/min
loading main= 2.7 lb/ft²
loading alt= 13 kg/m²
thrust/weight=

ee also

aircontent
related=
similar aircraft=
* XH-26 Jet Jeep
* Fairey Rotodyne
* Rotary Rocket
see also=

References

* Display information at Museum of Flight in Seattle, Washington
* [http://www.hiller.org/exhibits/thefirst100years.html Hiller Aviation Museum timeline] "The First 100 Years of Aviation"

External links

* [http://www.hiller.org/thefirst100years.shtml Hiller Aviation Museum: The First 100 Years of Aviation]
* [http://www.nasm.si.edu/research/aero/aircraft/hiller_hoe.htm National Air and Space Museum Hiller HOE page]
* [http://www.youtube.com/watch?v=MV2lS5mUSj4 Video of Hiller HJ-1 Hornet hovering]