The L-242 airplane was the result of two concurrent studies which were being pursued prior to Lockheed’s final submission to the OS-130 competition. The first such study was based on the original requirements for a Navy fighter outlined in the first issue of OS-130. The second study was for a day fighter airplane based on requirements for the United States Air Force (which ultimately yielded the legendary F-104). In subsequent changes to OS-130, it became apparent that Navy requirements were paralleling the concept of a day fighter being developed for the Air Force and, as a result, Lockheed’s proposal was essentially the airplane developed for the Air Force modified to fulfill the requirements of a carrier-based airplane for Navy use.
The table is a supplemental summary of the airplane characteristics and performance which describes more clearly the combat capabilities and compares the airplane performance directly with the final requirements of OS-130 and its Amendments.
Lockheed claimed that the L-242 would be entirely adequate to fulfill Navy requirements. It had a top possible combat speed of 1,000 kts, corresponding to a Mach number of 1.74, which was far in excess of the Mach 1.2 required. In addition, it had a combat radius of 495 miles, by the use of droppable fuel tanks and combat at Mach 1.2, which exceeded the 400 miles required.
Since this airplane was identical in general design to the F-104, its internal fuel capacity was not quite sufficient to fulfill the radius specified in OS-130. Thus, the 188 mile radius with a combat speed of Mach 1.2 on internal fuel only was somewhat below the 300 miles required. Lockheed argued that the relatively light weight, coupled with design simplicity and small dimensions, would make the L-242 ideal for carrier-based service.
The previous figures and table show several spot points summarizing the performance of the airplane when the Wright TJ-31-B4 and the General Electric X-24 engine was installed in place of the Wright TJ-31-B3, which was proposed for the basic model. Since these engines could have been installed in the airplane with very little change, and since their development promised to provide a large increase in performance, they provided ample assurance to Lockheed and to the military services that the basic L-242 airframe was not too small to have a large growth potential, both in range and speed, as development engines progressed. With no change except the installation of the X-24 engines, it was apparent that the L-242 could have had a top speed of over Mach 2.0 at 35,000 ft and could potentially have had a combat radius of 550 nm based on a combat number of Mach 1.2 and the use of the same external fuel tanks as then incorporated.
Lockheed emphasized that the L-242 design was a simple airplane based on structural and aerodynamic concepts which had been demonstrated to be valid. Thus, the development of a production airplane would not have been a long process and involved a minimum expenditure for the performance and the utility of the weapon system. The company further emphasized that the development of this model for both the Air Force and Navy would certainly diminish the development costs for both services and provide production costs below those which obtainable for two different airplanes designed for specifications which were so nearly identical.
In the development of the Lockheed L-242 design, the initial effort was spent on an airplane to fulfill the requirements of a non-afterburning fighter which had a combat radius of 300 miles and a high speed of Mach 1. The development of this design was pursued with a substantial effort until November 25, 1952 — in spite of the fact that previous fighter investigations by Lockheed had indicated that this level of performance was quite low and that, on the basis of contemporary power plant data, a lighter smaller, airplane could be achieved using an afterburner type of power plant. These design studies were continued, however, because Lockheed was acutely aware of the Navy’s earnest effort to reduce the size, weight and complexity of its fighter aircraft.
The final design for the non-afterburning fighter did not include a main gear because of the potential saving in weight provided by the mat landing system.
It was gratifying, in the comparison of the airplanes, to see that the supersonic design was not vastly larger, and was only more complicated by the inclusion of the afterburner. It was the considered opinion of Lockheed that the final requirements were more realistic and have resulted in a more useful airplane for the Navy.
The following sections summarize the operational characteristics of the airplane, including details of combat performance on alternate missions, combat armament, carrier suitability and adaptability to later designs of carrier landing facilities. In addition, its maintenance features and emergency escape provisions are outlined. Another section is devoted to the development background for this particular design, with discussions on why the various design details were created. Finally, detail descriptions of each of the airplane basic components are given along with a section on the design for producibility and a summary of the weight.