McCulloch MC-4

The McCulloch Model MC-4 was an American tandem-rotor helicopter and was the first helicopter developed by McCulloch Aircraft Corporation, a division of McCulloch Motors Corporation. It was evaluated by the United States Army as the YH-30 and the United States Navy as the XHUM-1.

Design and development
The MC-4 was a larger version of the earlier Jovanovich JOV-3 tandem-rotor helicopter and was developed by the McCulloch Aircraft Corporation. The JOV-3 was developed by Jovanovich when he headed the Helicopter Engineering and Research Corporation. The JOV-3 first flew in 1948. In 1949 Jovanovich moved to the McCulloch Motors Corporation where an enlarged helicopter the MC-4 first flew in March 1951. It was followed by a similar MC-4C and three evaluation helicopters for the United States Army (as the YH-30). The MC-4C was slightly larger than the MC-4. When the MC-4C was certified in 1953 it was the first tandem-rotor helicopter to be certified in the United States for commercial use. Three examples were evaluated by the United States Army as the YH-30, but Army's evaluation showed the helicopter to be underpowered.

The YH-30 had a steel-tube framework with a light metal skin, A single 200 hp Franklin piston engine was horizontally mounted amidships and powered two intermeshing tandem rotors. It had a fixed wheeled tricycle landing gear with a castering nose wheel.

No civil or military orders were received and Jovanovich formed his own company, the Jovair Corporation, where he modified the MC-4C as a prototype for a four-seat private helicopter designated the Sedan 4E. The Sedan 4E was powered by 210 hp Franklin 6A-335 engine. A version with a turbo-charged engine was designed as the Sedan 4ES and a more basic Sedan 4A for agricultural use. By 1965 a small number of Sedan helicopters were built. In the early 1970s McCulloch regained the rights to the helicopter designs.

Variants

 * McCulloch MC-4
 * Prototype with a 165hp Franklin engine, two built, one for evaluation by the United States Navy.


 * McCulloch MC-4A
 * Variant for evaluation by the United States Navy as the XHUM-1, two built.


 * McCulloch MC-4C
 * Protoype with a 200hp Franklin engine, one built and an additional three for United States Army evaluation as the YH-30.


 * Jovair Sedan 4E
 * Production civil four-seat version powered by a 210hp Franklin 6A-335 engine.


 * Jovair Sedan 4ES
 * Sedan with a turbo-charged 225hp Franklin engine.


 * Jovair Sedan 4A
 * Simplified agricultural version.

Military designations

 * YH-30
 * Military version of the MC-4C, three built.


 * XHUM-1
 * Two MC-4As for evaluation by the United States Navy, later re-designated HUM-1.

Operators

 * United States Army
 * United States Navy
 * United States Navy

Survivors
In 2008 two MC-4Cs are still registered in the United States. The Pima Air and Space Museum has a HUM-1, registration N4072K. The Yanks American Air Museum at Chino are restoring a MC-4C to flying condition although they have no plans to fly it. It may be N4071K or N4091K. One of the three YH-30 miitary prototypes is preserved by the US Army Aviation Museum at Fort Rucker, Alabama. It is c/n 001 and has the military serial 52-5837. As of April 2013 it remains in a storage building and is not on public display.

Media
An MC-4C was used in the 1954 science fiction production Gog.