Key Points and Summary: While the F-16 is getting a lot of press coverage as it is battling Russia in the Ukraine war, a powerful F-16 variant that did not make it into the U.S. Air Force, the F-16XL, also deserves attention.
-The F-16XL, a cutting-edge prototype by General Dynamics, aimed to replace the F-111 Aardvark with enhanced range and payload capabilities.
-With its radical delta-wing design and advanced aerodynamics, the F-16XL demonstrated superior performance during testing, flying farther and carrying more munitions than standard F-16s.
-However, the U.S. Air Force ultimately selected the F-15E Strike Eagle, citing its dual-engine power, greater payload, and superior climb rate.
-Despite its rejection, the F-16XL found a second life with NASA for supersonic and aerodynamic research.
-Today, it remains a fascinating “what-if” in aviation history, showcased in museums as a reminder of its potential.
The F-16XL Fighter: Why the Air Force Chose the F-15E Instead
The F-16XL is a curious airplane that never made it to active duty with the U.S. Air Force.
It was designed to replace the F-111 Aardvark.
The fighter had a radical delta wing-shaped design and was an outgrowth of the Enhanced Tactical Fighter (ETF) program.
The delta wing was large – almost double the size of the standard F-16 wings.
The F-16XL was the product of the Supersonic Cruise and Maneuver Prototype (SCAMP) project. The SCAMP program wanted to examine whether an F-16 could incorporate supersonic transport aerodynamics on Air Force airplanes.
This could increase lift and create a more agile airframe.
Defense Contractor Got an Assist from NASA
General Dynamics was the defense contractor behind the development of the F-16XL and the company expended vast amounts of effort and resources into research and development starting in 1980.
They partnered with NASA and utilized the space agency’s wind tunnels for 3,600 hours of testing. Finally, two F-16XLs were built.
The fighter had a longer fuselage than the base model F-16 – extended by about 56 inches.
The design also lacked ventral fins.
Was the F-16XL Better Than the F-16?
One would think that the “XL” nomenclature meant “extra-large,” but other wrinkles made the F-16XL unique.
The prototypes were the stars of testing and evaluation. They proved they could fly twice as far and carry double the payload compared to the F-16.
What They Were Saying in 1983
I looked back to decades-old media coverage of the F-16XL, and people in charge of the warbird were enthusiastic after that test run.
“The F-16XL flight-test program has conclusively demonstrated that the XL performs as predicted. This performance level represents a significant increase in mission capability for USAF. Coupling this with the affordability and low risk of the F-16XL presents USAF with a viable way to increase mission capability while simultaneously growing to a forty-wing TAC force structure,” said D. Randall Kent in 1983, who was then Vice President and Program Director for the General Dynamics F-16XL program.
The F-16XL Was Seen As an Expensive Time Suck
Unfortunately, the Air Force and General Dynamics spent significant funds developing the F-16XL. Even though the prototypes dominated the skies in 1983 after three years of work, this was seen as a lengthy testing period compared to other fighters available.
The Air Force ended up choosing the F-15E Strike Eagle instead. It would take many years and even more money to get the F-16XL into full production mode. The F-15E had two engines with greater thrust, speed, and climbing ability. It could reach supersonic speeds easily at any altitude. The Strike Eagle had a bigger munitions payload and could carry many missiles and bombs.
The F-16XL had one Pratt & Whitney F100-PW-200 turbofan engine. Maximum speed was MACH 1.8. The service ceiling was 50,000 feet with a maximum range of 2,850 miles. The climb rate was 62,000 feet per minute.
The two F-16XLs were then placed in storage, but NASA took an interest and brought them out of safekeeping at Edwards Air Force Base in California in 1988. The idea was to study air flow around the wings, leading them to research how the F-16XL could accelerate to top speed.

F-16XL. Image Credit: Creative Commons.
Time for an Experimental Period
“Each of those aircraft was then used in a variety of experiments that only concluded in 1999. That included a 1995 sonic boom study, in which F-16XL #849 flew 200 feet behind a NASA SR-71 to probe the boundary of the SR-71’s supersonic shock wave. These tests measured and recorded the shape and intensity of the shock waves. Those studies helped NASA’s High-Speed Civil Transport (HSCT) program engineers to better understand supersonic shock waves in order to reduce sonic boom intensity near populated areas,” according to Peter Suciu.
The F-16XL last flew in 1996, and then it went back into storage at NASA Dryden Flight Research Center.
One F-16XL later became a museum piece at Edwards Air Force Base, and another sat for visitors to peruse at Museum Air Park outside the National Museum of the Air Force at Wright-Patterson Air Force Base in Ohio.

On October 5, 1993, Langley’s F-16XL High Lift jet was rolled out with a dynamic yellow and black paint job for Aero-Dynamic Flow Studies in High Speed Research.
About the Author: Dr. Brent M. Eastwood
Brent M. Eastwood, PhD, is the author of Don’t Turn Your Back On the World: a Conservative Foreign Policy and Humans, Machines, and Data: Future Trends in Warfare, plus two other books. Brent was the founder and CEO of a tech firm that predicted world events using artificial intelligence. He served as a legislative fellow for U.S. Senator Tim Scott and advised the senator on defense and foreign policy issues. He has taught at American University, George Washington University, and George Mason University. Brent is a former U.S. Army Infantry officer. He can be followed on X @BMEastwood.

Syed Ahmed
January 17, 2025 at 3:27 pm
this is for 3rd tier friends of the US like India and Taiwan etc who cannot be trusted with the F35….
PseudoExpertent
January 17, 2025 at 9:18 pm
XL arrived or came upon the scene at the wrong time.
Today, f-35s also powered by only one engine.
But today’s aircraft are built with a high composition of carbon fiber and other non-metals like graphene.
If russia or china (or ukraine) are given XL’s original blueprints today, they will build it and serialise its production.
XL was never really given any opportunity.
pagar
January 17, 2025 at 9:40 pm
Could XL deliver nukes.
Yes, I think so.
Today, countries all over the globe are racing to build nuclear arsenals.
The bigger the better.
For example, china is increasing its nuke arsenal.
Reason is it’s surrounded by several nuke-armed countries plus the dreaded ever menacing forward-deployed US nukes.
Just to its rear is india which is now advancing by leaps and bounds in its nuclear capability.
But is that really something to worry about since others are pretty much going the same route.
Yes, because india is extremely untrustworthy and totally shady.
India’s political elites have always been hounded by unseen or invisible shadows since independence from UK (which shoulders a hella lot of responsibilty for this) and thus perennially cast a jaundiced eye toward its neighbors.
That spells potential mortal danger and thus china needs to increase its nuke arsenal.
Moreover, night and day, or perhaps day and night, washington or the deep state is hurling tons of money at defense firms to conjure up new major weapons of mass destruction like the B-21, the B61-13 and other weapons like the NUCLEAR-TIPPED LRSO.
In the light of all those latest developments, XL should never have been discarded.
It was a big mistake.
Spuwho
January 18, 2025 at 1:17 am
Dumb article. Talking about a prototype airframe that never went anywhere in the 70’s and 80’s and referencing it to a war action happening today.
Next you will publish an article about how we should consider the Avro Arrow and how it could be used in a conflict with China.
The XL was a pig. The 52 inches made it overweight and severely underpowered. Just an attempt by LockMart to extract more dollars from USAF.
ZivBnd770
January 18, 2025 at 6:30 am
What a beauty. I wish it could have seen production. But it makes me wonder if it would be possible to do something similar to the wing and fuselage on the F-35 to gain more range and payload without ruining the low RCS.
An “F-35D” with twice the payload and more than half again the range would be VERY useful in the Pacific region. It would not be cheap to design and build, but it would be cheaper and faster than a clean sheet design.
William H Warrick III MD
January 18, 2025 at 12:24 pm
There aren’t going to be any Wars in the future. The Oreshnik is going to end them.
Joe
January 20, 2025 at 3:46 am
To the clown who said lengthening the aircraft made it worse, you’re a moron. It increased payload, range, and improved capabilities while keeping the speed and agility. It could Supercruise, something the pig F15E COULD NOT DO. With modern updates in engine technology and air frame construction the F16xl easily destroys the piece of shit F35.