advanced variant, the CL-1200-2, was to have redesigned center and rear fuselage sections that could accommodate a modern turbofan engine as an improvement on the J79 turbojet. This turbofan engine was to be the Pratt & Whitney TF30-P-100 as used in the F-111F. The TF-30-P-100 would have provided a 60 percent increase in thrust at maximum power. The air intakes were located in the same position as on the F-104, but they were to employ variable shock cones with four-inch movement in place of the F-104's fixed cones to optimize engine performance over a wide speed range. Armament The Lancer was intended to retain the 20 mm General Electric M61A1 cannon as its primary armament, although a 30 mm DEFA gun could be fitted as an alternative. For the ground-attack role nine weapons stations were provided: one under the fuselage, three under each wing, and one at each wingtip. Two Nord Aviation AS-30 missiles could be carried on the inner underwing pylons, while up to 12,000 lb (5,450 kg) of ordnance could be carried on short-range ground-attack missions. Air-to-air missiles designed to be carried were AIM-7 Sparrow (maximum of four) and AIM-9 Sidewinder (typically, six to be carried with a maximum of 10 possible). External fuel tanks of the same type and capacity as the F-104 could be carried on the wing tips and on underwing pylons to increase ferry range. Performance The estimated gross weight was 35,000 lb (16,000 kg) with maximum external load, and a top speed of 1,700 mph (2,720 km/h, Mach 2.5) at 35,000 ft (10,700 m) was envisaged. The takeoff run was estimated to be 1,450 ft (440 m) in the intercept configuration; only 52% of that required for the F-104G with a similar improvement on landing performance due to the slower approach speed. Lockheed's chief designer "Kelly" Johnson projected that the CL-1200-2 would be superior in air-to-air combat to any known fighter. Cost Lockheed carried out a comprehensive survey and believed that there was a worldwide market for an advanced design, low-price fighter aircraft over the decade of the 1970s. Other aircraft manufacturers also recognized the opportunity and this was the reason for the fierce competition for sales at the time. Lockheed calculations showed that even a 10% share of this market (750 aircraft) would be a worthwhile venture. They further reasoned that development costs for the Lancer would be approximately 70.5 million US