Adding to the problems, the zip fuel program was canceled in 1959. After burning, the fuel turned into liquids and solids that increased wear on moving turbine engine components. Although the B-70 was intended to use zip only in the afterburners, and thus avoid this problem, the enormous cost of the zip program for such limited gains led to its cancellation. This by itself was not a fatal problem, however, as newly developed high-energy fuels like JP-6 were available to make up some of the difference. Most of the range lost in the change from zip fuel was restored by filling one of the two bomb bays with a fuel tank. However, another problem arose when the XF-108 program was canceled in September 1959, which ended the shared development that benefited the B-70 program.