The YF-23's Weapons Bay Layout Was One Of Its Best Features And One Of Its Worst

Northrop's entry into the ATF tender had a big, ambiguous weapons bay that likely hurt its chances of being selected but would be prized today.

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As we continue our series on one of the most enigmatic, misunderstood and ahead of its time aircraft in military history—Northrop's YF-23 Black Widow that lost the Advanced Tactical Fighter (ATF) competition to Lockheed's YF-22 Lightning—we turn our gaze toward its unique weapons bay configuration. Like so many things YF-23, this feature had big potential benefits, but it also represented a heightened developmental risk for the USAF. In the end, it very likely damaged Northrop's prospects of supplying America's air superiority fighter of the 21st Century, and maybe for good reason at the time, but today, the YF-23's unique weapons bay configuration would almost certainly be highly prized. 

The YF-22 and YF-23 went about carrying their weapons in drastically different manners. The YF-22 featured a fairly straightforward affair, with a shallow weapons bay that spanned its lower fuselage configured to carry four AIM-120 AMRAAMS nestled alongside one another and two small bays that flanked the aircraft's waist—like a wild west gunfighter's belt—carrying a pair of shorter ranged AIM-9 Sidewinders. 

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ATF competitors side-by-side over the Mojave Desert.

The seeker heads on the Sidewinders would deploy into the slipstream at an angle once the side bay doors are open and before locking on and firing off their mounting rail at the enemy. The AIM-120s would be punched out of the ventral bay using a pneumatic trapeze-like vertical launcher. Each missile had its own one of these and could be launched freely regardless of the status of the other missiles in the bay. 

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F-22A showing its weapons bays. Note the three ejector-launchers situated in the main weapons bay. Each on carries a single AIM-120.

The final production configuration of the F-22 Raptor would hold six AIM-120C AMRAAMs internally—the clipped fins of this new model AMRAAM that was secretly in development during the ATF competition provided extra clearance for the two additional missiles—as well as the two sidewinders as originally envisioned. The F-22 can also carry a single GBU-32 1,000lb JDAM or four GBU-39 Small Diameter Bombs and an AIM-120 per bay or six Small Diameter Bombs per bay and no AIM-120s, giving the Raptor a limited standoff strike capability against medium sized and medium fortified structures, as well as smaller targets.

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Four SDBs and a single AIM-120 can fit into each of the F-22's main weapons bays. 

Northrop's YF-23, on the other hand, went with a far less straight-forward weapons bay configuration. Instead of shallow, largely conformal bays, the YF-23 had a single, coffin-like, cavernous weapons carrying cavity that ran from behind the cockpit, back into the area between the aircraft's widely spaced and very unique air intakes. The bay was covered by two very large outwardly swinging doors and the interior of the bay was far deeper than the one found on the YF-22, but also a bit narrower overall. 

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The technology demonstrator aircraft were designed to notionally carry three AIM-120s and two AIM-9s in this bay—three AIM-120s mounted in a staggered fashion on trapeze launchers and two AIM-9s attached to the bay doors. I say notionally because a useable launch system was never installed on either of the prototype airframes, although some reports state that a single instrumented AIM-120 was mounted in the aircraft's bay for fit checks and possibly to measure vibrations during a test flight. Lockheed's YF-22, on the other hand, actually test fired an AIM-120 during its demonstration phase, which was not even part of the ATF requirements, but was impressive none the less. It also further painted a picture that the YF-22 was a far more mature design than Northrop's offering.

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Lockheed's YF-22 executing an AIM-120 test launch. 

A big, deep weapons bay is great for air-to-ground applications, but it does invite potentially unwanted complexity for air-to-air applications. By stacking missiles above other missiles, it means that if one jammed, the ones behind it would not be usable—or worse. It also meant that an elaborate missile handling and launching mechanism would be required. This could add substantial weight and complexity to the design, and thus increase risk and possibly cost associated with it. At the same time, a big, deep, trough-like weapons compartment meant that the YF-23 could potentially carry substantial air-to-ground stores, including 2,000lb class weapons, and possibly even larger. Such a bay could also be subdivided for different types of off smaller weapons to be carried at one time. 

The YF-22 had far less air-to-ground potential but it also had none of the YF-23 weapons bay complexities and unknowns, and for what was supposed to be a thoroughbred air-to-air fighter the likes of which the world had never seen, putting a premium on air-to-ground capabilities that may pan out one day was not on the ATF program's to-do list. 

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Note the weapons bay seams are visible.

The final F-23 configuration would have been markedly different than its YF-23 progenitor. It would feature two weapons bays instead of one. A similar large bay roughly in the same place as the original, but also another smaller, shallower bay under the cockpit that would hold a pair of AIM-9 Sidewinders. By most accounts, this configuration would have allowed for four or maybe five AIM-120s and a pair of sidewinders to be carried, but some claim that elaborate and complex AIM-120 carriage contraptions could have drastically increased this to as many as eight or even 10 AIM-120s. Once again, this would rely on stacking missiles in magazines or using a form of a rotary launcher, among other concepts, some of which Northrop did receive patents for in the late 1980s when the ATF competition was underway. 

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A Northrop patent for a vertical fighter missile magazine from the ATF era. 

But any of these magazine designs could have left an F-23 pilot without a large portion of their arsenal if a missile jammed. And complex weapons carriage and deployment systems are not ideal for a fighter that constantly turns under the crushing force of 9Gs and is buffeted and vibrated like a jackhammer during hard maneuvering.

Like so many things YF-23, in retrospect, an ATF that could carry a diverse air-to-ground weapons load, including munitions capable of taking out large and well fortified targets—and especially a fighter that had better kinematic, range, and low observable (stealth) performance than even the YF-22—would be a near ideal combat aircraft today. In fact, designs eerily similar to the YF-23 continue to get pushed around as representing the next leap in manned fighter capability nearly three decades after the YF-23 took to the skies for the first time. 

Screencap via Youtube

Lockheed has put forward renderings of an aircraft that looks awfully similar to the YF-23 as an example of 6th generation fighter almost 30 years after the YF-23 lost to its own YF-22 ATF competitor. Read more about this here.

Even though the YF-23 may have represented a larger evolutionary leap in fighter design and had even more potential to evolve than its counterpart, the YF-22 was a safer bet based on the information available when the ATF decision was made. In other words, the YF-22 was a more mature, lower risk, and fully realized example of what Lockheed wanted to bring to life in the form of the F-22A than what the YF-23 represented. It was also a more traditional option, all of which were huge factors in the USAF's final decision. Their choice of the Pratt & Whitney F119 over the General Electric F120 was also thought to have been made on similar grounds.

I couldn't write this piece without discussing the long-standing rumors surrounding the existence of a YF-23 derived regional strike aircraft, largely referred to as the F/B-23. It wasn't long after the ATF program ended that talk began to spread of the USAF having an entirely different purpose in mind for the YF-23 design and the technology that informed it. There was even talk that one of the YF-23 ATF technology demonstrators was pulled from exhibition to be examined and components of it used for some form of follow-on program. 

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PAV-1 and its experimental F119 engines before restoration at Wright Patterson AFB. 

In the mid-2000s, models and renderings of an F/B-23 emerged. The design, dubbed the Rapid Theater Attack concept, was an enlarged and elongated version of the YF-23 with room for two crewmen and featuring more traditional exhausts and supposedly divertless supersonic intakes—a feature that was slated to make it onto production F-23A's as well. Literally, this was the supercruising, deep penetrating, hard-hitting, regional ranged strike machine that many of us had long dreamed of. An aircraft that possesses a multiple of the unrefueled combat radii found on tactical fighters and capable of transiting relatively long distances in short timeframes via sustained supercruise. 

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F/B-23 TRA model.

Such a concept made a lot of sense then and it still does today. And the YF-23's big weapons bay, expanded in this stretched version, could pack a lot of damage that could obliterate even deeply buried bunkers. Keep in mind, that once the F-117 was retired in 2008, the Pentagon had no tactical aircraft that could penetrate deep into enemy airspace and unleash 2,000lb class weapons. Only the B-2 strategic bomber would retain this capability until the F-35 would become operational a decade later. 

Northrop Grumman

Bill Sweetman, previously of Aviation Week fame, noted that the F/B-23 would have had "a 10,000-lb. internal bomb load, a Mach-1.6 cruising speed and a 1,250-nm unrefueled combat radius."

All this was happening as the USAF was pondering an FB-22 with similar, albeit likely less specialized capabilities as the YF-23, but the FB-22 would have had the advantage of leveraging much of the F-22's support and manufacturing infrastructure. It ends up that the USAF passed on both aircraft, although the concept seems to be making a something of a comeback as of late as Japan and even the U.S. eye a new heavy fighter that incorporates both the F-35's best attributes with those of an enhanced F-22 airframe. 

As for the F/B-23, or any other outgrowth of the YF-23 including a potential tactical reconnaissance variant, there is no hard evidence that anything of the sort ever existed in a prototype, let alone an operational form. But who knows, maybe one day we will find out that the YF-23 was recycled in certain respects for a deeply classified program, but for now, the fighter with serious bomber potential remains a dead-end in the annals of military aviation history. 

Contact the author: Tyler@thedrive.com