before take-off would not have permitted successful flight." The Northrop JB-1 suffered from numerous production and structural complexities as well as being overweight. The problem of persistent turbine failures coupled with the J-1s low thrust had already caused Northrop to seek another powerplant, the Ford pulse jet as used on the JB-2. That change coupled with the need to reduce the cost of manufacturing the JB-1A led to the development of the JB-10. In June 1996, the Western Museum of Flight restored the manned JB-1 glider. JB-10 With the successful USAAF flights of JB-2, and the inadequate performance of the GE B-1, the JB-1 program was reoriented towards pulsejet propulsion before the attempted first flight of the JB-1A. The remaining JB-1s were modified or completed as JB-10 missiles. The JB-10 was a radical redesign of the vehicle. A single PJ31-1 as was used on the JB-2 replaced the two troublesome B-1s. The explosives were buried in the wing instead of being in nacelles. Only the guidance electronics was left essentially unchanged. A new and much improved telmetry system was added. Testing of the JB-10 began in early 1945 and achieved only two partially successful flights out of 10 attempts. The longest flight of a JB-10 was only 26 miles on April 13, 1945. That short flight was ended by longitudinal instability which was a persistent problem of JB-10. The JB-10 cost $55,425 each to build while the JB-2 cost $8,620 each. As a competitor to the JB-2 the JB-10 was not a contender. The Northrop program's priority had already been reduced in November 1944. In March 1946 the JB-10 program was terminated. References books Mindling, George, and Bolton, Robert, U.S. Air Force Tactical Missiles 1949–1969: 'The Pioneers', 2008, Lulu Press Cruise missiles of the United States JB-1 1940s United States military gliders World War II jet aircraft of the United States World War II guided missiles of the United States Aircraft first flown in 1944 Flying wings