YR-4

From OnAirpower.org

YR-4 Hoverfly

Designation: YR-4 Manufacturer: Sikorsky Nationality: American First Flight: January 13, 1942 Remarks: The first helicopter used by operationally by the U.S. military, in Burma during World War II

[edit] Sources

• Wikipedia entry for Sikorsky R-4

• Sikorsky R-4B Hoverfly  at National Museum of the USAF

• First Helicopter Rescue  at National Museum of the USAF

[edit] References