JB-4
| JB-4 | |
|---|---|
| Type | Air-to-surface missile | 
| Place of origin | United States | 
| Service history | |
| In service | 1945 | 
| Used by | United States Army Air Forces | 
| Specifications | |
| Mass | 3,000 pounds (1,400 kg) | 
| Wingspan | 12 feet (3.7 m) | 
| Warhead | High explosive | 
| Warhead weight | 2,000 pounds (910 kg) bomb | 
| Engine | Ford PJ31 pulsejet 660 lbf (2.9 kN) | 
| Operational range | 75 miles (121 km) | 
| Maximum speed | 445 mph (716 km/h) | 
The JB-4, also known as MX-607, was an early American air-to-surface missile developed by the United States Army Air Forces during World War II. Using television/radio-command guidance, the JB-4 reached the flight-testing stage before being cancelled at the end of the war.