Original priority was given to an air-to-ground version, confidence in the initial results was so high that the USAAF had ordered 3,500 rockets before any had been actually fitted to an aircraft and it was hoped to have them operational in time for Operation Torch, the invasion of North Africa, in October 1942. The successful launch of an M8 from a Curtiss P-40E fighter on July 6, 1942 resulted in a procurement order for 600,000 units. Development began on a reloadable launcher that could be fitted in the bomb bay of a Douglas A-20 bomber, but this never became operational. There were considerable problems with the propellant, the fuses and the underwing launching tubes, all of which considerably delayed operational deployment.