A contract for the escape rocket of the Apollo spacecraft launch escape system was awarded to the Lockheed Propulsion Company by NAA. The initial requirements were for a 200,000-pound-thrust solid- propellant rocket motor with an active thrust-vector-control subsystem.

After extensive study, Lockheed was directed to remove the control subsystem. A letter contract change was subsequently made with Lockheed to develop and manufacture a pitch-control motor to replace the thrust-vector-control subsystem. In conjunction with the use of the pitch-control motor, the escape-motor thrust was reduced to 155,000 pounds. References: 16 .