It's a typical pattern of evolution. Each generation recognizes something that was absurd or incredible in the past as ordinary in the present. As time passes, evolution takes hold again, and we are left in awe of something new and truly amazing once again. Mankind is full of such advancements in technology in many regards. Gunpowder, repeating rifles, submarines, and of course the advent of the airplane. By World War II the airplane had seen it's third iteration when jet power entered the playing field. By Korea, the jet was a common staple in air supremacy. By Vietnam, it was almost the law. The path to get to each of these points was full of haunting ideas that shaped air power today.
Just after the Vietnam War, we were greeted with familiar faces in air superiority, early warning, strategic strike, tactical strike, patrol, interceptions, and escort groups. The first of these was the F-14 Tomcat in 1970, followed by the F-15 Eagle and A-10 Thunderbolt II in 1972, the F-16 Falcon in 1974, and the F/A-18 Hornet in 1978. The introduction of the F-117 Nighthawk in 1981, however, signaled a change in the mold and design of aircraft to come. Northrop Corporation and Lockheed Martin both found themselves locked in battles with each other, clashing over federal funding to create aircraft suitable for U.S. Air Force (USAF) missions. Northrop walked away with a win with it's B-2 Spirit in 1989 - a weapon system that reshaped all future requirements for bombers in the USAF arsenal. Yet, there was another competition that the two were engaged in that Lockheed was destined to win: the Advanced Tactical Fighter (ATF) program.
The F-15 Eagle
|Dimensions:||63'9" L, 42'10" W, 18'6" H|
|Weight:||28,000 lbs (empty), 44,500 lbs (average), 68,000 lbs (maximum)|
|Speed:||1,650 mph (max), ~920 mph (cruise)|
|Range:||~1,050 miles (combat), 3,000 miles (ferry)|
|Variants:||10 (base), 12 (prototype), 7 (RDTM)|
|First Flight:||27 July 1972|
|Service History:||Introduced, 9 January 1976|
It Starts a Bit More Conventional...
In 1965, the Secretary of Defense, Robert McNamara, advised the USAF to consolidate it's aircraft assortment by selecting a single multirole air superiority fighter (much to GEN Curtis LeMay's objections and ongoing chagrin). The aircraft would effectively initiate the phasing out of the century aircraft, such as the F-100. The initial push was to use an already ongoing research project - the F-X program - to meet the needs of replacing even more aircraft. The requirement called for a fighter capable of Mach 2.5 and could fulfill a ground-attack mission set. The U.S. military was beginning to favor single-set designs for their applications, such as the F-4 Phantom II which had been purchased by the U.S. Navy, Marines, and the USAF. Mission set demands turned to production urgency, when the Soviet Union announced it's MiG-25 in 1967. The fighter was capable of exceeding Mach 2.5, meaning that the need for closing the gap was much more immanent.
The USAF selected McDonnell Douglas's concept for an air superiority fighter late in 1967, but in the meantime, the Navy had opted to break away from waiting on USAF decisions. It opted to go with the VFX program, which would eventually produce the F-14 Tomcat. The selected USAF design in 1967 finally produced project designs in 1968. The final design proposal was accepted late in 1969, and resembled a non-variable wing version of the F-14. These wings were later updated to improve strength at higher speeds, thus giving a more delta shape. This final revision was the F-15A Eagle - also referred to as the Streak Eagle.
The first flight was in 1972, with the introduction into the USAF following in 1976. The design more than met the requirements outlined by the Air Force, and subsequent revisions on the design were proposed and injected later in the projects development. This included export models, all-weather models, and even naval models. Subsequent updates and revisions led to the introduction of the F-15E Strike Eagle - a slightly larger and heavier ground-attack variant - in 1989. By the time the Berlin Wall collapsed, the need for high-speed and high-altitude deterrents saw a changing set of mission requirements again. In fact, the requirement for an upper hand on the Soviet MiG-25 and MiG-31 had been submitted already in 1981. After all, high speed was great, but what if you could just hide in plain sight...waiting for the enemy to come to you? Better yet, what if the enemy never even saw you coming?
The Beginnings of the Advanced Tactical Fighter (ATF) Program
The initial requirements for what would become the ATF program find their origins in 1981, when the USAF began to examine options for replacing the F-15 Eagle. By this time, the USAF had four successful stealth aircraft that had navigated through it's channels. Three of those were from the Blackbird family, while the other was the Nighthawk - another aircraft that grew out of Lockheed's Skunk Works. The USAF was ready to make stealth a standard part of it's requirements in future requests for information and proposals. In addition to stealth, there were requirements specified for super cruise and short-takeoff-and-landing (STOL).
By 1985, the USAF was prepared to begin receiving design proposals. No fewer than twenty different designs were submitted by seven different defense contractors.
Boeing's proposal that was created by it's Phantom Works, was cannibalized and repurposed later by Rockwell for it's X-31 project in 1990. The research derived from this design eventually went on to aid development on the Eurofighter Typhoon. The other Boeing concept borrowed on designs from contemporary Soviet aircraft (such as the Su-27) with modified vertical stabilizers.
Grumman's proposal borrowed technology from their ongoing research on their F-5 platform. ATF-G1 resembled the X-29 with forward swept wings and front mounted canards.
Lockheed's original proposal resembled what seemed to be a design that cannibalized the Blackbird family, featuring modified airframe, similarly powerful engines, and canards. Lockheed's final iteration would be radically modified and changed from this submission.
Two of three Northrop designs resembled their eventual concept that went to the prototype phase. The Missileer is the design that Northrop pursued for the program upon their selection.
The cooperation was unique in the ATF program. Whichever two contractors were selected, some of the remaining contractors would provide developmental aid in a predetermined partnership. When Lockheed and Northrop were selected, the RDE teams were divided according to these agreements. (Lockheed worked with General Dynamics, and Boeing. Northrop worked with McDonnell Douglas.) The selection for these two contractors was made in July of 1986.
Ongoing research and development projects were being used to collect data during the duration of the building phase. For example, McDonnell Douglas was collecting data on the F-15S/MTD through NASA's Dryden Test Research Center. Data on thrust-vectoring and STOL technology was being accumulated to get a better grasp and understanding of how the technology interacted with different airframe concepts. After years of research, the prototypes were ready in 1990 for their first flight.
Things Got Real
Final revisions for the prototype phase of production began in 1988, with smaller aeronautic revisions being incorporated as the project carried forward. The ATF specifics were finalized by December of 1988, and by early 1989, production of the first prototypes was well underway. The first of the prototypes to reach completion was Northrop's entry, which made its first successful flight in August of 1990. Lockheed's entry followed suit a month later in late September.
At the same time as the ATF prototypes were being produced, the Navy was once again examining options for the replacement of many aircraft in it's fleet, particularly the F-14 Tomcat. The Navy began examining the feasibility of incorporating the USAF's ATF program selection into their own requirement set (NATF). Various spin-off designs were generated, including the wildly reimagined Super Tomcat 21 and the Naval YF-22B. However, due to realization of issues with previous endeavors of the same type - particularly with the F-111 Aardvark - the Navy selected to make interim updates to the Tomcat fleet with the F-14D. The eventual selection that fulfilled the NATF role was the F/A-18E & F Super Hornets.
In the meantime, Northrop and Lockheed, along with the USAF, began to embark on a fifty-month testing period on a pair of airframes each. The Lockheed pair were designated N22YF and N22YX, respectively, and both were named Lightning II. Northrop's pair were designated 87-0800 and 87-0801, respectively, and had unique names individual to each craft. Northrop's PAV-1 (87-0800) was named Black Widow II and PAV-2 (87-0801) was named Gray Ghost.
The YF-23 Black Widow II & Gray Ghost
|Dimensions:||67'5" L, 43'7" W, 13'11" H|
|Weight:||29,000 lbs (empty), 51,320 lbs (average), 62,000 lbs (maximum)|
|Speed:||1,450 mph (max), 1,060 mph (cruise)|
|First Flight:||27 August 1990|
|Service History:||Cancelled, 1993
Current Status Unknown
It Had a Spiritual Connection
Northrop's design changed the least among the contenders for the ATF program from start to finish. They also had the benefit of an ongoing contract to develop the Air Force's new premier bomber, the B-2 Spirit. Borrowing in technology, research, and even design, the Northrop YF-23 was an insidious looking entry. The aircraft was sleek, and many have previously argued that it's design may have been more stealthy than it's Lockheed rival. The wings were diamond-shaped which helped stabilized the aircraft while reducing drag. The tail was V-shaped with a blended design. The YF-23 borrowed it's concealed engine design from the B-2, where two engines (GE or P&W 119/120 depending on which PAV you're examining) were placed and exhausted through heat-defeating troughs. The intakes were nestled into the wings near where the main body of the aircraft met the front shoulder of the wing.
The YF-23 made it's first flight about a month before Lockheed's entry. Northrop had already been pacing the YF-23 for about six flights by the time Lockheed's first demonstrator made it off the ground. Still, Northrop had to cut corners in order to achieve this feat from the legendary defense contractor. It cannibalized parts from existing McDonnell Douglas designs in order to meet the needs of the program - just to reach demonstrator status and to reduce costs. All of the landing gear and control surfaces were effectively repurposed from other aircraft, such as the F-15. Effectively, the YF-23 was a culmination of "the best that the military has to offer" as it stood in 1988. Northrop proposed to push aviation into the next generation by wildly reimagining airframe design. After all, many features in the design of the airframe had worked with their previous defense contract where the B-2 won out against Lockheed's "jumbo" F-117 - Senior Peg. However, Lockheed's error in the Advanced Tactical Bomber (ATB) program ultimately would be Northrop's error in the ATF.
Northrop's prototype had some rather muffled specifications as both of the airframes had two separate powerplants, as previously mentioned. Gray Ghost was notably slower than Black Widow II, with the supercruise difference of about .17 Mach's. The top speed of the aircraft was and still is classified, with the published speed of Mach 2 being "a conservative estimate." These figures were based upon the sixty-plus hours of flight testing between the two airframes.
Gray Ghost also made it's debut flight much later than Black Widow II, taking to the skies for the first time in October of 1990 - over two months after her sister.
The YF-22 Lightning II
|Dimensions:||64'6" L, 43'0" W, 17'9" H|
|Weight:||33,000 lbs (empty), 62,000 lbs (approx, max)|
|Speed:||1,450 mph (max), 1,040 mph (cruise)|
|Range:||~800 miles (combat)|
|First Flight:||29 September 1990|
|Service History:||Prototype Retired, 1993
First Production Model Complete, 1997
Production Model In Service
The Skunk Works
Lockheed had abandoned it's initial ATF concept by 1987 in favor of a more modern design that incorporated elements of new stealthy technology, with design features that were tested and proven to work. As mentioned previously, Lockheed also had a bit of a chip on it's shoulder after being the losing contender in the ATB program against Northrop. Couple this with the Skunk Works then-fifty years worth of experience in stealth technology RDE, and have have yourself a recipe for motivation and excellence. Internally, the ATF prototypes in Lockheed were referred to as Lightning II, a moniker that was instead later given to another Skunk Works aircraft, the F-35. The YF-22, like it's competitor, was a reimagined design - much like the Lockheed stealth fighter that came before it.
The YF-22 prototypes also had two different engines between them, the same ones that were equipped on the two YF-23 models. The difference in speed between the two prototypes was slightly less than the Northrop models, clocking in at .15 Mach's worth of difference. Once again, the YF-22's were both spec'd above Mach 2, but no maximum speed was ever definitively described. The design was a bit more squared as well, with most wing surface area featuring a lazy-diamond to tapered-delta design. Lockheed successfully launched the first YF-22 in September of 1990, and the maximum supercruise speeds were achieved in the weeks immediately following this test. Boeing was charged with the building of the wings, and Lockheed specified that the control surfaces of the wings be large to increase stability. Internal fuselage components and landing gear was supplied by General Dynamics.
The YF-22 logged almost double the amount of hours in testing compared to the YF-23. It was also the only ATF entry to carry an armed payload and fire that payload. This included the use of AIM-9 Sidewinder missiles and AIM-120 AMRAAM missiles, all kept within it's internal weapons bays. Lockheed was able, therefore, to display the full extent of capabilities of it's flight demonstrator.
However, with increased testing comes increased risk, and the YF-22 fell victim to this 1992 when PAV-2 crashed on approach to Edwards Air Force Base. While the pilot survived, the aircraft was grounded permanently after major repair. Problems with flight-control software were cited as the official reason for the crash. This software was supposed to aid in the control of the aircraft and make automatic corrections so that the pilot could focus on his field-of-view. The failure of this software resulted in an uncontrolled oscillation which caused the craft to roll and pitch into the ground.
Unfortunately, There Can Be Only One
By the end of 1990, most of the testing in relation to the competition was complete, and the USAF had made their selection of who would be continuing on to production. Northrop had successfully created an aircraft that was fundamentally faster, sleeker, and stealthier, but it was unable to out maneuver the YF-22. The Lightning II proved to be a much more agile aircraft with it's four tail features and thrust-vectoring nozzles. The YF-22 was also capable of a more diverse payload which in turn expanded it's mission capabilities to include ground-attack. On 23 April 1991, the YF-22 was formally announced as the selection for the ATF mission requirement.
The initial estimate of production quantities was expected to exceed 600 aircraft. These numbers were modified as time wore on, and by the time production began delivering, this number had been reduced to 300. The immediate requirement called for the development and delivery of both single-seat (A) and two-seat (B) designs, fulfilling a pre-existing precedent that already was ongoing in the aircraft (excluding the F-117).
At the same time, Pratt & Whitney was awarded the contract for production of it's F119 powerplants for the F-22. In the midst of the ATF program, both Pratt & Whitney and General Electric were engaged in their own competition. The YF120 was subsequently cancelled, but resurfaced again for a brief period as the F135 prototype for the F-35, before being totally scrapped in 2011.
The YF-22 fulfilled the requirements of the USAF, and early estimates and suggestions indicated that it could have also worked for the NATF. PAV-2 continued research flights well after the selection had ended for the ATF partially for this reason. However, another major reason for this was to acquire necessary data to create a perfect machine. The YF-22 was far from perfect, it was stuck to a rigid timeline that required something airworthy in a relatively short amount of time. Between 1991 and it's crash in 1992, it logged an additional sixty hours of flight time that was used in RDE for the production variant. PAV-1 had since been retired by the time PAV-2 had crashed.
Both Northrop and Lockheed remained on the hook for the NATF however, that requirement was relinquished when the Navy announced that it was not going forward with the program in 1992. Any hope the YF-23 had at entering U.S. military service in it's current incarnation was therefore ended at that time. However, Lockheed was just beginning production of it's most advanced aircraft ever, and by 1996 the first flight was just around the corner.
The F-22 Raptor
|Dimensions:||62'1" L 44'6" W, 16'8" H|
|Weight:||43,340 lbs (empty), 64,840 lbs (average), 83,500 lbs (max)|
|Speed:||1,500 mph (max) 920~1,220 mph (cruise)|
|Range:||1,800+ miles (normal), 530~680 miles (combat), 115 miles (scramble)|
|First Flight:||7 September 1997|
|Service History:||First Production Model Complete, 1997
"You'll Never See It Coming..."
They called her "The Spirit of America." That was the name of the first production F-22A that was unveiled on 9 April 1997. It was that evening at the unveiling ceremony that the plane was given it's formal and proper name: Raptor. This was the name that superseded all of the other names that was given to it: Rapier, SuperStar, Lightning II, and Senior Sky. Outside of this, the aircraft temporarily was assigned the designation of F/A-22 to highlight it's ground-attack capabilities, but by the time the aircraft was ready to enter service, the USAF opted to keep the standard F-22 designation.
The Raptor began it's flight testing in 1997. Eight of the first production F-22's went through rigorous flight testing at Edwards Air Force Base between 1997 and 2003. This occurred due to requirements in the Engineering, Manufacturing, and Development (EMD) phase of production. EMD ensures that parts are being manufactured to specification, any needs are addressed, and crews are briefed on problems and resolutions. The EMD phase was significant to the F-22 program. Between the prototype YF-22 and S/N 4001 (Spirit of America), the Raptor had transformed into a slightly smaller and more round aircraft. Surface features on the wing were shrunk, the tail was modified, the undercarriage was updated to include additional optional pylons, and the wings saw more curvature off of the overhanging delta. This was the final evolution of the project that started with a miniature Blackbird in 1981.
The F-22 incorporated the latest in stealth technology, having a radar cross section (RCS) roughly the size of a large marble, and features a system capable of monitoring it's own radar presence. Previous stealth technology (save for the B-2 Spirit) had been dependent on the application of radar absorbing paint however, the F-22 utilized it's geometric shape, control surfaces, material, and infrared concealment with thrust-vectoring engines as a means to reduce it's RCS. This meant that maintenance on the stealth components of the Raptor was much lower than on earlier aircraft.
As a means to maintain it's stealthiness, the F-22 has three internal weapons bays. Two are located on the side near the engine intakes, which both house a single AIM-9 Sidewinder each. The main weapons bay is located underneath the main body and can house anywhere from four to eight various weapons, including six AIM-120 AMRAAM's, eight 250 lb. bombs, or two 1,000 lb. JDAM's. The F-22 was also equipped with a modified M61A2 Vulcan cannon that fires up to 480 20 mm rounds. Four removable pylons can be mounted on the undersides of the wings to carry two external fuel tanks and up to four additional AIM-9's. These pylons are removed when not required to maintain the aircraft's stealth composure. On typical patrol and intercept missions, these pylons would not be used, and reduced RCS would enable (and has enabled) the F-22 to fully check a target at range before it is even detected by the offending aircraft. This allows the F-22 to be the "last surprise" for a hostile enemy in friendly airspace, if necessary.
The Raptor successfully reached operational readiness in 2005, with the first deliveries being made to Nellis Air Force Base in Nevada in January of 2003. Additional deliveries were made subsequently to Tyndall, Elmendorf, and Langley AFB's in the following months and years. However, the F-22 faced backlash from critics in Washington. Many, including the Secretary of Defense, argued that the F-22 was not necessary in the modern multi-domain warfare environment, and that it was a product of the Cold War. The upcoming demands of the Joint Strike Fighter program also increased budget worries and production slowdowns. Finally in 2011, all production on the F-22 lines was ordered to be halted at just 187 deliveries on top of the eight EMD aircraft. The last Raptor was delivered to the USAF on 2 May 2012.
The aircraft's main deployment thus far has been in support of the Global War on Terror (GWOT), and it's proxy wars. This includes deployments to Syria, Iraq, and Afghanistan. Much like previous stealth aircraft, the aircraft was barred from export, and therefore it is only operated by the USAF. Both Israel and Japan have expressed interested in the purchase of the aircraft, however, both were not able to do so despite their standing in NATO and association with the United States. Of the 195 aircraft produced, 190 remain airworthy today.
The Story Hasn't Ended...
If you believed that is all there was, is, or will be to this story, you'd be grossly mistaken. No, in fact, you'd be just wrong.
In 2016, the USAF re-examined the restart of production of the F-22 Raptor for an additional 194 aircraft. While it was determined at the time that cost exceeded the value, additional examinations of the feasibility of restoring the F-22 program have been introduced since due to the ongoing struggles in the F-35 Lightning II program. It is far from certain - rather unlikely - that production would resume on new F-22 airframes, however there is precedent for such a move within the USAF. Therefore, it is entirely possible that production of the F-22 could resume sometime in the future, albeit slim.
The F-22's trial and paces did not end with the single variant of the F-22A. Rather, there were at least three other designs that were proposed variants of the F-22 between 1993 and 2008. This includes the original production map which indicated both a single-seat F-22A, and a twin-seat F-22B. The F-22B, despite being outlined in the production map was never produced, and no known model was ever even produced of such an aircraft.
At the time of the ATF program, as previously mentioned, the Navy was also looking at a replacement for it's aging F-14 Tomcat. Both ATF contenders were engaged in working with the Navy on fulfilling this requirement ahead of it's cancellation in 1992. Lockheed's proposal was the F-22N, a swing-wing version of the F-22 that would also carry an arresting hook for carrier operations. The aircraft never left the drawing board, and the only images of anything like it are artistic renderings and paintings that were simply used for illustration. It is not known how swing-wing technology may have impacted the RCS of the aircraft either.
Another proposed variant of the F-22 was the F/B-22, a fighter-bomber aircraft capable of delivering quick-strikes on targets in contended airspace. The proposed aircraft would have been the replacement for the F-15E Strike Eagle, but cost effectiveness coupled with ongoing proven results with existing technology led to this concept being abandoned. It was momentarily restored 2004, when the USAF announced the need for a new interim bomber, where it gained traction in aviation circles. The F/B-22 would have been a blended-delta-wing aircraft that would incorporate the same main body chassis and engines as the F-22, with dual internal bays capable of heavier payloads. However, this aircraft was effectively shelved when the USAF announced it was moving to the Next-Generation Bomber program which required an aircraft with greater range. This program eventually evolved into the B-21 Raider program.
The most interesting variant, however, was the X-44 MANTA project that was proposed by Lockheed in 1997. MANTA stood for Multi-Axis No-Tail Aircraft, and the renderings of the X-44 certainly show a unique depiction of such a concept. The X-44 was to feature a tapered blended-wing design with no tail, essentially keeping the rest of the aircraft body the same as the production F-22. Control was maintained entirely through use of thrust vectoring, while larger wings enabled a greater payload, better fuel capacity, better range, and fewer working parts. The project ran parallel and was slightly inspired by the McDonnell Douglas / Boeing X-36 TFARA (Tailless Fighter Agility Research Aircraft) that flew the same year. The X-44, however, never left the drawing board, and outside of an isolated artistic rendering or two, nothing ever came of it beyond feasibility studies. It's contender in the X-36 program also was terminated by 2002, despite generally high-performing results in a scaled down study.
Other variants have been proposed in the span of the time from prototype to service, however none have come to fruition. The X-35 program borrowed RDE from the F-22 program in the JSF program, however it is not inherently a variant of the F-22. However, it's existence has effectively ended any alternative purposes for the previously planned F-22 variants, and therefore it is unlikely that any future production on the F-22 platform or production line is on the horizon.
The F-22 remains in ready service with the USAF and is expected to remain so through at least 2040.
...Not Even For This One.
Despite the YF-23's failure to capture the eye of the USAF, Northrop continued to market the aircraft for other purposes, including the NATF. When the NATF was cancelled in 1992, Northrop did what it does best: stored it. At least the RDE work, anyway. The YF-23 has made several reappearances since the termination of the NATF. The first was for the NGB program for an interim bomber - the same program that Lockheed entered the F/B-22 in. Unfortunately, this program was also terminated (along with the plans for the larger YF-23 variant, the F/B-22, and the B-1R). With that, the immediate chances for the YF-23 to return domestically seem to have waned for now. However, Northrop has a history of developing frames that are repurposed later. Their B-2 Spirit bomber was based on a bomber concept that preceded it by forty years, and many speculate this may be a similar case for the YF-23.
More recently, in 2018, Northrop responded to a request made by the Japanese military to work on the research and development of a late-stage fifth generation, first-stage sixth generation aircraft. The initial working model of the aircraft was the Mitsubishi X-2 Shinshin, but further research was requested by Japan. Some speculate that the YF-23 program may filter into the Japanese program, but this is not confirmed, nor corroborated by Northrop nor the Japanese Defense Ministry. Despite speculation of Chinese and Russian theft of the Northrop design, most of the reasoning and justification behind these is no more than apparent similarities not dissimilar from how aircraft have constantly borrowed in design and technology in the past.
However, the YF-23's advanced stealth technology for it's age, coupled with it's parent's history of staying ahead of the demand certainly leave one to wonder. As of now, the YF-23's status is declared retired, but much like the SR-71 Blackbird and the F-117 Nighthawk, there is evidence to suggest that the RDE on this program may not be concluded. That fact, however, is not a historians job - but rather the work of researchers, engineers, and surely the errant conspiracy theorist.
Maybe They Were Both Right
In 2008, a requirement was outlined that signaled that the constant that is change was about to occur once again. That generational change that transforms, not just modifies. The USAF described a preliminary requirement for a sixth generation aircraft. Thus far, to public knowledge, the only one to respond to this request has been Boeing. The F/A-XX program has been outlined to complement the F-35 program and to replace the F/A-18E & F Super Hornets. This would place it sometime in the 2025-2035 timeframe. The Boeing design has evolved since 2008. The latest 2013 rendering includes a tailless design, tapered-full-delta wings, front canards, thrust vectoring, and even a slave-drone tagalong. All of these things had been presented in some shape, way, or form through various designs and variants over twenty years earlier in the ATF program.
It's difficult to claim that there is a conclusion to something that is ongoing, be that a project, evolution, or mission. As we have explored, the tale isn't over here yet, and many of these subjects could include miles upon miles of additional writing and research. The YF-22 entering service as the F-22 means that it's tale is far from over. NASA's involvement with the ATF program could certainly imply eventual test evaluation and research of the F-22 platform down the road, leading to even more variations and designs that currently aren't seen as a priority. Meanwhile, Northrop's design almost certainly lives on in some form, be that simply in a closet somewhere, research sharing with a foreign ally, or something else that we don't see right now. And what of Boeing's work in the F/A-XX program? Surely Lockheed and Northrop will have something to present for such a project. Will we see the YF-23 return in some way in the F/A-XX program? How will Lockheed proceed? It's all a matter of perspective and waiting to see what comes of it.
However, one thing is for certain, all things are within a pattern of evolution. Now it's just a question of if we skipped a step in 1988, or if we're about to see another major advance today. Regardless, this has been the tale of how the first fifth generation fighter and it's sister were born.