Dragoljub Jovanović

D. K. (Dragoljub Kosta) or "Gish" Jovanovich (January 24, 1916 – November 12, 1983) was born in Yugoslavia (pre-Communist Kingdom of Yugoslavia). He lived in Philadelphia and later settled in Southern California. He was a Serbian-American helicopter designer, inventor, and pioneer in autogyro technology.

Jovanovich and Frank Kozloski founded the Helicopter Engineering Research Corporation (HERC) in Philadelphia, Pennsylvania in 1946. HERC was the predecessor of Jovair. Jovanovich and Kozloski previously worked for Piasecki Helicopter Corporation where Jovanovich's patented tandem rotary design was used on the Piasecki PV-3.

The first helicopter they designed was the HERC JOV-3. This was first flown in 1948. They used the Boulevard Airport (formerly William Penn Airport) as their base.

In 1949 Jovanovich and Kozloski transferred to the McCulloch Aircraft Corporation, the new helicopter and aircraft division of McCulloch Motors Corporation. The design principles of the JOV-3 were incorporated into the McCulloch MC-4, which first flew in March 1951. In 1952, the MC-4C, a modified MC-4, was acquired by the US Army in 1952 for testing, but was deemed underpowered and none were further ordered.

In 1955 Jovanovich designed a rotor for Howard Hughes' Hughes 269. This was followed by hub blades for the three-blade light helicopter, the 1958 Del Mar DH-1 Whirlymite series, and the hub for the Hughes 500.

In 1960 Jovanovich formed Jovair Corporation to continue development of the MC-4. A new version the Jovair Sedan 4E called the Jovairin was type approved by the FAA in March 1963. The billionaire, Bill Lear, tried to spark interest in its production without success.

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