On May 19, Roy W. Johnson, ARPA Director, notified AOMC that the Saturn second stage would be the first stage of the Titan. After discussions by ARPA, AOMC, Air Force, and Martin Company personnel, ARPA authorized AOMC to enter into direct contracts for modification and procurement of Titan hardware, and on July 24 the appropriate government offices were told by Army Ballistic Missile Agency (ABMA) to conclude letter contracts with Aerojet-General Corporation and The Martin Company. Five days later, ARPA ordered all AOMC Saturn second-stage effort suspended. Johnson later testified that Herbert F. York, DOD Director of Defense Research and Engineering, had informed him: "I have decided to cancel the Saturn program on the grounds that there is no military justification therefore, on the grounds that any military requirement can be accommodated by Titan-C as proposed by the Air Force (Titan-C was a booster, not yet developed, of lower thrust than the Saturn and intended for use in the Dyna-Soar program), and on the ground that by the cancellation the Defense Department will be in a position to terminate the costly operation being conducted at ABMA." Johnson testified that he had been ready to concur in the cancellation of the Saturn program if it were established that the Titan G could be developed for about 75 percent of the cost of Saturn and if the Titan C could accomplish the military missions projected for the next ten years. York then appointed a Booster Evaluation Committee which convened on September 16.