Republic-Ford JB-2

JB-2/KGW Loon
Republic-Ford JB-2 at the Steven F. Udvar-Hazy Center. 2018
TypeCruise missile
Place of originUnited States
Service history
In service1945–53
Used byUnited States Army Air Forces
United States Air Force
United States Navy
Production history
ManufacturerRepublic Aircraft
Willys-Overland
Ford Motor Company
Produced1944–45
No. built1,391
Specifications
Mass5,000 pounds (2,300 kg)
Length27 feet 1 inch (8.26 m)
Diameter34 inches (860 mm)
Wingspan17 feet 8 inches (5.38 m)
WarheadHigh explosive
Warhead weight2,000 pounds (910 kg)
EngineFord PJ31 pulsejet
660 lbf (2.9 kN)
Operational
range
150 miles (240 km)
Maximum speed 425 miles per hour (684 km/h)
Guidance
system
Radio command
Accuracy0.25 miles (0.40 km) at 100 miles (160 km)
The pulsejet's forward support pylon's differing shape on the original V-1 ordnance
A JB-2 being inspected by USAAF personnel at Wendover AAF, 1944.
JB-2 being air launched for flight test by a Boeing B-17 during testing of the weapon at Eglin Field, 1944
In flight after air launch, 1944
Ground preparation prior to air launch, 1944
A JB-2 being prepared for a test launch at Holloman Air Force Base in May, 1948.
JB-2 Loon before launch at PMTC Point Mugu in 1948
A Loon being fired from USS Cusk in 1951

The Republic-Ford JB-2, also known as the Thunderbug, KGW and LTV-N-2 Loon, was an American copy of the German V-1 flying bomb. Developed in 1944, and planned to be used in the Allied invasion of Japan (Operation Downfall), the JB-2 was never used in combat. It was the most successful of the United States Army Air Forces Jet Bomb (JB) projects (JB-1 through JB-10) during World War II. Postwar, the JB-2 played a significant role in the development of more advanced surface-to-surface tactical missile systems such as the MGM-1 Matador and later MGM-13 Mace.