The Lockheed CL-1200 Lancer was a late 1960s company-funded proposal for a new and improved F-104 Starfighter. It was intended for the export market and was in direct competition with the Northrop F-5E Tiger II, Dassault Mirage F1, Northrop YF-17 and the McDonnell Douglas F-4F Phantom. Lockheed hoped to capitalize on its F-104 production experience through commonality of parts and systems, and mimimize expense by reusing tooling, jigs and existing factory facilities. Lockheed was also experienced in consortium production and further hoped to continue this arrangement with the CL-1200. It was projected that CL-1200 deliveries could begin in 1972.
Borrowing heavily from the F-104 design the new type featured a new high-mounted, increased span wing and low-mounted, enlarged tailplanes. Both features were incorporated to improve flight handling characteristics and short-field performance. The CL1200-1 was to have used an uprated version of the F-104 engine, the General Electric J79 with a later variant known as the CL1200-2 to be powered by a Pratt and Whitney TF-30 turbofan.
The CL-1200-1 was entered in the International Fighter Aircraft competition, but since the Northrop F-5 was named as the winner in November 1970, the primary market for the Lancer was lost, and the project was terminated with no examples completed.
The X-27 was an experimental designation assigned by the USAF  to a proposed high-performance research aircraft derived from the CL-1200 Lancer project. The X-27 was to have tested advanced technology high-performance engines and equipment. Again, the X-27 project did not proceed beyond the mock-up stage.
The CL-1200-2 (sometimes referred to as the CL-1600) was a proposed development of the X-27 for entry into the Lightweight Fighter Competition in 1972. The CL-1200-2 was not proceeded with when General Dynamics and Northrop designs were given contracts for the YF-16 and YF-17. The design was similar to the X-27 but had round intakes with shock cones and a different fin.
A further variant was proposed for the United States Navy was designated the CL-1400 or CL-1400N. It was based on the forward fuselage, intake and wing of the CL-1200-2 with the rear fuselage of the X-27.
Intended as a successor to the F-104, the Lancer was another product from Lockheed's Skunk Works (the official alias for the company's Advanced Development Projects branch). Clarence L "Kelly" Johnson headed the department during this period, while Skunk works designers carried out all aerodynamic studies and wind tunnel testing on the type.
The CL-1200 was to have kept the basic F-104 fuselage structure, increased in length to provide 46 percent extra internal fuel capacity. The fuselage extension consisted of a 30 inch plug between the standard F-104 front and center fuselage sections. Unlike the F-104, the rear fuselage section was to be constructed using titanium alloy for the frames, longerons and skinning around the jet exhaust. The major revision of the design was a shoulder-mounted wing of 53 percent larger area  which was also moved further aft. The new wing had a span of 29 feet and still featured leading and trailing edge flaps but gained new leading edge extensions, while the 10 degree anhedral of the Starfighter was retained. The flap system was designed to be either manual or automatic in operation; the system configuring them as required for load factor, airspeed and altitude. The new inner wing panels featured an additional trailing edge flap which doubled the area in comparison to the F-104; this would have improved short-field performance and lowered the landing speed. The Boundary Layer Control System of the F-104 was deemed unnecessary due to the increased flap area and was deleted. The outer wing panels were virtually identical to those of the F-104.
The tailplane was increased in area, split into two separate surfaces, and moved down from the top of the vertical fin to the lower rear fuselage in order to avoid the downwash effects from the high-set wing at high angles of attack which could have resulted in a deep stall condition.  The repositioning of the tailplane was also a measure taken to eliminate the Starfighter's known pitch-up problems. For commonality the landing gear, hydraulic and electrical systems remained essentially identical to the F-104. The strengthened windshield from the F-104S was to be used to withstand the aerodynamic heating of flight at higher Mach numbers. A two-seat trainer version was planned, as was a reconnaissance and all-weather interceptor version. This would have been achieved by simply using the existing forward fuselage sections and avionics from the TF-104G, RF-104G and F-104S.
The initial variant of the Lancer was to be the CL-1200-1, powered by a single J79-GE-19 turbojet which was an uprated version of the engine used in the F-104. The second, more 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.
The Lancer was intended to retain the 20 millimeter General Electric M61A1 cannon as its primary armament, although a 30 millimeter 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 pounds 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 maximimum 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.
The estimated gross weight was 35,000 pounds with maximum external load, and a top speed of 1,700 mph at 35,000 feet was envisaged. The takeoff run was estimated to be 1,450 feet in the intercept configuration; only 52 percent 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.
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 1970's. 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 percent 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 Dollars (1970). Unit costs depended on the size of the production run with $2.7 million being quoted in the case of a production run of 500 aircraft and $2.4 million for twice this number. Lockheed also researched the operating costs for the first 10 years of operation which included the provision of spares, ground equipment, technical manuals, and both maintenance and flight training. For a production run of 500 aircraft the support cost over 10 years was given as $330 million, reducing to $180 million if 1,000 Lancers were built. Operating costs over 10 years were also calculated. By adding the total of all these costs Lockheed claimed that their product offered significant savings over both the Dassault Mirage F-1 and the F-4F Phantom when their equivalent costs were shown.
 Project cancellations
In November 1970 the Northrop F-5-21 was named the winner of the International Fighter Aircraft competition; following which no interest was shown in the CL-1200 by existing F-104 operators and the project was then terminated.
 CL-704 VTOL
Another cancelled Starfighter derivative, pre-dating the CL-1200 Lancer by eight years and not directly related, was the CL-704 VTOL strike and reconnaissance aircraft originally proposed in 1962 as a joint venture between Lockheed and Short Brothers and Harland Ltd. Designed purely for VTOL operations, it was to have had seven vertically-mounted Rolls Royce RB.181 lift engines in each of the enlarged wingtip pods; the main forward propulsion being provided by a Rolls Royce RB.168R mounted in the fuselage. The project was cancelled due to the numerous complexities involved and the highly advanced development of the Hawker P.1127.
A larger-winged F-104 variant was proposed as an alternative to the MRCA (Multi-Role Combat Aircraft) then being designed as a multi-national European project. Nothing ever emerged, and the MRCA eventually became the Panavia Tornado.
 X-27 Development
The USAF planned to buy at least one experimental Lancer under the designation X-27 (called the CL-1600 by Lockheed) for Mach 2.6 testing. The X-27 was to be similar in overall configuration to the Lancer, but was to feature modified engine air intakes having a rectangular shape. However, the X-27 program received almost no U.S. Congressional or Air Force support. Due to the lack of funding, no flight-capable aircraft were constructed. One full-scale mockup was built by Lockheed, although up to three fuselages had been converted prior to the shutdown of the project.
 Specifications (CL-1200-2 / X-27)
Data from  NB: These are estimated figures given by Lockheed as neither type flew.
* Crew: One
* Length: 57 ft 3 in / 53 ft 2 in (17.45 / 16.2 m)
* Wingspan: 29 ft 2 in / 28 ft 7 in (8.89 / 8.7 m)
* Height: 17 ft 2 in / 16 ft 2 in (5.23 / 4.9 m)
* Wing area: 300ft² (28m²
* Airfoil: Bi-convex
* Empty weight: 17,885 / 17,250 lb (8,112/ 7,800 kg)
* Loaded weight: 24,385 / 32,500 lb (11,061 / 16,000 kg)
* Max takeoff weight: 35,000lb (15,900kg)
* Powerplant: 1× Pratt & Whitney TF30-P-100 turbofan
o Dry thrust: 15,000 lbf (66.7 kN)
o Thrust with afterburner: 25,000 lbf (111.2 kN)
* Maximum speed: 1,477 / 1,260 knots at 35,000 ft (Mach 2.57 / 2.19) (1,700 / 1,450 mph, 2,720 / 2,330 km/h)
* Range: 367 nm combat radius with 4,000 lb (8,800 kg) bombload / 1,836 nm range (420 / 2,100 mi, 680 / 3,400 km)
* Service ceiling In excess of 60,000 ft (>18,300 m)
* Rate of climb: 60,000ft/min (300m/s)
* Takeoff run: 1,450 ft (440 m)
* Landing run: 2,060 ft (930 m)
* 1 × 20 mm General Electric M61 Vulcan cannon with 725 rounds
* 1 × 30 mm DEFA cannon with 400 rounds as alternative.
* Offensive load of up to 12,000