The Northrop/McDonnell Douglas YF-23, or Black Widow II, is a story from a different history of aviation. Portrayed in the late 1980s as a possibility for the Air Force’s Advanced Tactical Fighter competition, it was an experimental attempt to define air superiority for the next several decades. Designed to fly quicker and stealthier than the world’s leading fighters at the time, the YF-23 was meant to be the F-15 Eagle’s natural successor. It never went into production, but much of what it pioneered about low observability and cruise performance at high speeds became a shadow over later designs, disproportionate to the number of prototypes built.
The test the Air Force put to itself was unrelenting: create an airplane that could dominate the battlespace well into the 21st century. That required combining a very low radar signature, long-range high-speed performance without fuel wastage, responsive handling, and sensors and avionics that would enable a single pilot to look and control much more of the fight. Several of the better teams reacted. Northrop allied with McDonnell Douglas; Lockheed teamed up with Boeing; General Dynamics joined the battle, too. Each entry pushed aerodynamics, stealth shaping, propulsion, and systems integration to new extremes.
Right from the outset, the YF-23’s form did all the talking. Its diamond-shaped wings, canted V-tail, and sleek, integrated fuselage were not merely stylistic choices; every panel line and curve was chosen to attenuate radar energy and reduce returns. Internal armament bays and the lack of external projections helped to preserve that stealth profile in all directions.
Under the skin, as well, the YF-23 was state-of-the-art. The fuselage blended into the wing in a shape that reduced drag at speed, and the intakes and nacelles for the engines were deeply recessed to minimize radar-reflective features. The V-tail was supplied to save the radar cross-section while still allowing the control authority necessary at high angles and high.
Power would be supplied by advanced prototype engines: the Pratt & Whitney YF119 on one model and the General Electric YF120 on the other. The YF120’s variable-cycle design—transferring from high-thrust sprint to fuel-efficient cruise—was especially ambitious, foreshadowing how fighters in the future would be able to sacrifice sprint speed for long-range patrol.
With that kit, the YF-23 demonstrated consistent supersonic cruise—often referred to as supercruise—at speeds near Mach 1.7, enabling it to cover long distances in a short period of time without afterburner. Its exhaust and cooling systems were also designed to extinguish infrared signature, making the aircraft harder to detect via heat-seeking equipment.
The cockpit reflected the airplane’s focus on decision-making by the pilot. The controls were positioned for rapid access, the displays prioritized mission-critical information, and a fly-by-wire design provided accurate command. Electronic warfare and sensors onboard were optimized to give the pilot a determining edge in high-density, highly contested environments.
Weapon carriage was internal to maintain stealth, yet the bays were sized to handle long-range missiles like AIM-120s and short-range sidewinders where required. A 20mm gun was included for close combat—a compromise with the realities of air combat, which some stealth ideas were not willing to sacrifice in the name of signature reduction.
When the prototypes flew head-to-head in 1990, both the YF-23 and Lockheed’s YF-22 impressed. The Air Force decided to go with the YF-22, citing a combination of factors: the YF-22’s thrust-vectoring was more maneuverable, its design was found to be lower risk to manufacture, and Lockheed’s proven stealth reputation was heavily influential.
Loss in the flyoff did not send the YF-23 to the dustbin of history. Its design, aerodynamic takeaways, and management-by-design techniques influenced engineers and designers for decades ahead. The two flyoff aircraft, known informally as Black Widow II and Gray Ghost, sit in museums today as tangible reminders of an era when creative thinking knew no bounds in what could be done in a fighter.
The YF-23 story lives on because it speaks to something greater than itself: technological advancements don’t always need production lots to leave their mark. As a prototype in and of itself, the YF-23 reshaped stealth, propulsion, and aerodynamic design priorities. To pilots, designers, and flight enthusiasts, it’s a heady what-if—and an indication of just how groundbreaking engineering can change the future even if an aircraft never gets a chance to take a shot in irritation.