Firstly, the F-16XL is rarely mentioned when it comes to the most daring fighter jets ever designed. However, the F-16XL remains one of the most amazing “what if” stories in the history of modern aviation to those who are familiar with the design of the aircraft and the air power. This new version, the XL, was made as a completely different concept from the classic F-16, to such an extent that this single-engine fighter could be taken to the very edge of the sky. Eventually, it lost to the F-15E Strike Eagle, but it still details a lot of characteristics of the plane of the present and future, which proves to us that sometimes new things make their impact on history differently.
The most notable aspect of the F-16XL was undoubtedly the cranked-arrow delta wing, a design that, in fact, more than doubled the wing area compared to that of the standard F-16. In addition to giving the jet a look reminiscent of what people in sci-fi movies would depict as future spacecraft, it also brought some extensive performance benefits, which were very attractive at that time.
Traditional delta wings were often unpopular because they were highly draggy at low speeds and had low control, but the innovative concept of the XL wings provided a firm and tight overall drag figure, thereby the so-called supersonic wing was able to be traversed by using it with the slightly steeper trailing edge and even the speed control problem due to the less steep part was solved.
Over the wings, more lift was also available, room was offered for more fuel, and also the capability of an amazing number of weapons- 27 hard points were compared with only 9 of the standard Fighting Falcon; consequently, the plane turned out to be a platform with vast possibilities and powerful ones at that.
In no way was the F-16XL just an extended or enlarged wing variant of the first F-16. It was capable of going beyond Mach 2, and it could be maneuvered at over 50,000 feet and could take as much as 15,000 pounds of munitions on board. By having an extended capacity for fuel, it was able to go in combat at distances of about 1,100 miles, thus making missions over quite a distance possible.
Referring to the agility aspect, the XL managed to pull off 5 G turns in less than a second; therefore, it could outmaneuver the 1st series F-16A and the old type of F-4 Phantom. The point of the large wing, however, was that while the jet could still air-burst very agilely, the drag factor and energy levels over longer durations were affected; thus, it was suitable for quick strikes rather than long dogfights.
General Dynamics decided to make the F-16XL a reality to satisfy the Air Force’s requirements of a multi-use, two-fold role fighter that would step in and take over from the F-111, which was then getting old. The features exhibited by the F-16XL during competitions against the McDonnell Douglas F-15E prototype were such that it won over the hearts and minds of the test pilot crew and evaluation commission.
However, the day was won by the most practical choice: the twin-engine F-15E offered more payload, had long-range, and posed less risk in development. The decision of the Air Force to go for the Strike Eagle, thereby taking the opportunity of the XL to serve on the front lines to an end, was made in 1984.
The F-16XL was not only accepted by NASA as the holder of two prototypes for future research, but was also given a second life by NASA. The plane was involved in several research projects that included laminar flow studies, drag reduction experiments, and supersonic transport design. Its oddly-shaped wing served as a perfect model for the study of airflow over a wide range of speeds, and thus the data it had produced was directly connected to the development of further aircraft, for example, the F-22 Raptor, as well as the F-35 Lightning II. Until 2009, the XLs continued to be present in NASA’s research programs, constantly providing valuable insights long after their military prospects had ended.
Even though the F-16XL did not serve in the military, it is still vividly remembered in the design of the fighter jet. Basically, it was the demonstration that the most lightweight and the most maneuverable of fighters could become an aircraft to deliver long-range strike without the loss of essential performance.
Its modular construction, experimental aero-dynamics, and emphasis on multirole capability were the early signs of the design disciplines that are dominant in today’s advanced fighter jets. Therefore, the best memory of the XL’s legacy is a recognition that it may not be the most prominent aircraft of those that change the way the future of flight is conceived by engineers and pilots.