What are the most stealthy military jets the United States has developed? To some degree, it depends on what one counts as a military jet and what is counted as stealth. The upcoming high-end Collaborative Combat Aircraft, aka loyal wingman drones, like the Anduril YFQ-44 and General Atomics YFQ-42, could also fit the criteria at a stretch, but this list will limit itself to just manned fighter jets. This means large and secretive aircraft like the RQ-170 and RQ-180 are excluded.

It should be noted that modernized 4th-generation fighter jets like the F-15EX and the F/A-18 Super Hornet come with significantly reduced radar cross-sections (RCS) and some other features of all-aspect stealth, like advanced passive AESA radars. The United States currently has two stealth fighter jets in service, namely the Lockheed Martin F-22 Raptor and the Lockheed Martin F-35 Lightning II. Additionally, the Lockheed F-117 Nighthawk is considered the world’s first operational stealth combat aircraft, and it remains in limited service. The United States is racing to develop the next-generation Boeing F-47 as its future air dominance fighter jet.

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Lockheed F-117 Nighthawk

RCS approx. 0.001–0.01 m²

The Lockheed F-117 Nighthawk is considered the first operational stealth aircraft. It was designed as an attack aircraft to hunt down and destroy Soviet AWACS aircraft like the A-50 « Mainstay. » But this role was soon passed on to an even stealithier and advanced aircraft that the USAF was working on. That program would eventually lead to the development of the F-22 Raptor.

Lockheed Martin says, « The F-117 Nighthawk was developed in response to the urgent national need for a jet fighter that could operate completely undetected by the enemy. In true Skunk Works fashion, it was developed rapidly and in complete secrecy. » The aircraft is built with a distinct faceted shape as it is made from two-dimensional flat surfaces. This reflects its age and the fact that engineers had to design the aircraft without computers.

As computers became available and could run complicated equations, engineers were able to make subsequent stealthy aircraft, like the B-2, with curved surfaces. Despite its age, it has an estimated frontal RCS of around 0.001–0.01 m². For reference, Russia’s supposedly ‘5th-generation’ Su-57 is thought to have a front RCS of around 0.01–0.1 m² or an order of magnitude greater than the US Air Force’s 1980s F-117 made without computers.

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Lockheed F-22 Raptor

RCS approx. 0.0001–0.0005 m²

The F-22 Raptor was a generational leap compared to all the aircraft that came before it. The US Air Force had developed the F-15 Eagle to overmatch any fighter jet the Soviet Union could field. At the time, the US got the jitters from reports of the Mikoyan-Gurevich MiG-25 Foxbat and developed the F-15 to beat it, only to find out later on that the MiG-25 was not nearly as capable as feared, and the F-15 had been over-engineered.

With the F-15 as the world’s most advanced air superiority fighter, the US used it as the benchmark for the F-22 Raptor. The F-22 was developed as a no-expense-spared program and was to be the best of the best. It was so advanced that the concept of fighter jet generations became popular as a way to explain what a leap in capability it represented. It was marketed as the world’s first 5th-generation fighter jet. When it entered service in 2005, it was virtually unbeatable in its air-to-air dominance role. It was good at being a silver bullet at defeating any other fighter jet in military exercises, but the rare occasion it lost in an exercise became reported news.

This is very much a case of the exception proving the rule. It should be stressed that it is very difficult to estimate an aircraft’s radar cross-section; it depends on many factors, including the perspective from which the aircraft is being observed. With that said, Globalsecurity.org lists the F-22 as having the frontal radar cross-section of 0.0001 m2. For reference, a bird is listed as having an RCS of 0.01 m2. The F-22 is set to be the first US aircraft to have loyal wingman drones (CCAs), which are expected by around 2029. The Air Force is also considering upgrading about 32 older Block 20 training Raptor variants that Washington is not keen on retiring.

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Lockheed Martin F-35 Lightning II

RCS approx. 0.001–0.005 m²

The F-35 first entered service in 2015 and is regarded as the most advanced fighter jet in the world today. In some respects, the F-35 can be considered three different aircraft as the conventional F-35A, STOVL F-35B, and carrier-based F-35C are all substantially different from each other. The F-35 is designed as a multirole stealth fighter optimized for penetration of contested airspace and suppressing and defeating enemy air defense.

Whereas the F-22 Raptor is highly specialized in its air dominance role, the F-35 is designed to be more of a versatile platform. It is able to carry out a larger range of missions, including electronic warfare. When Canada and Finland considered their next-generation fighter jet replacements, the F/A-18 was paired with the EA-18G, the Saab Gripen E with the GlobalEye AWACS, and the F-35 competed alone. A leaked Canadian report showed the F-35 achieved a near-perfect score — leagues ahead of its closest competitor.

The F-35 has a significantly greater RCS than the F-22, although it has other advancements in all-aspect stealth by virtue of being a newer design and lessons learned from the Raptor. In the air superiority role, it is generally regarded as the second best in the world, only behind the Raptor. It should be stressed that the F-35 is still maturing, and it has not yet reached its full potential. Its frontal RCS is estimated to be around 0.001–0.005 m².

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Northrop-Grumman B-21 Raider

RCS approx. ≤ 0.00001 m²

The B-21 Raider is listed here instead of the B-2 Spirit as the Air Force has now received its first two flying prototypes and is expecting the aircraft to come into service in 2027. The B-2 Spirit remains the world’s only stealthy operational strategic bomber, and it will continue to serve into the 2030s. Still, one limiting factor when it comes to the B-2 is that there are only 19 of them left in inventory after mishaps. Northrop Grumman says, « The B-21 Raider will be capable of penetrating the toughest defenses to deliver precision strikes anywhere in the world. The B-21 is the future of deterrence and the world’s first sixth-generation aircraft to reach the skies. »

The accolade « 6th-generation » is typically one restricted to fighter jets, not bombers. Northrop calling the Raider 6th-gen could be just marketing puffery, or it could be a hint at something else. In the past, aircraft would be developed for a specific mission (e.g., strike, ground attack, air dominance, bombing), but those distinctions have been eroding for decades. Now, most fighter jets are multirole aircraft, and even the highly specialized Raptor has been used in a ground attack role. It seems plausible that the distinction between bombers and fighters will blur as the B-21 and F-47 come into service.

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It is perhaps better to think of these aircraft as highly advanced, super-sensing, supercomputing command centers. They are systems-of-systems that will command advanced loyal wingman drones. It’s unclear how much even the F-47 will be a fighter jet in the traditional sense. The Air Force has now received its first B-21 two flying prototypes and is expecting the aircraft to come into service in 2027. Estimating the RCS of the B-21 is speculative, with some placing it at around ≤ 0.00001 m² or two orders of magnitude lower than the older B-2 Spirit.

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Boeing F-47

RCS Approx. 0.00001–0.00005 m² (very speculative)

In 2025, Boeing was announced as the winner of the manned fighter jet component of the Air Force’s Next Generation Air Dominance (NGAD) program. The demonstrator is known to have first flown in 2020, and the first representative prototype is now in building, and the first flight is expected in 2028. The aircraft is expected to enter service by around 2030, perhaps a bit sooner. Procuring this jet has become a matter of urgency as the US finds itself in Great Power Competition with China.

It is unclear what the F-47 will look like. There are only two official partial renders of the aircraft, and the Air Force has hinted that these renders could contain misdirections to fool Chinese and other engineers. So while the renders show it has canards, it’s unclear whether it actually does have canards or not. As with other upcoming 6th-generation fighter jets, it is intended to be a system-of-systems networked with other assets and controlling loyal wingman drones (called Collaborative Combat Aircraft).

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Estimating the F-47’s RCS is highly speculative. Given that it is to replace the F-22 Raptor in the air dominance role and the Raptor achieves a frontal RCS of 0.0001–0.0005 m², it is plausible that it could be as small as 0.00001–0.00005 m². That would give it the RCS somewhere between a grain of sand and a marble. In the meantime, the Air Force is upgrading its fleet of F-22s with stealthy drop tanks, software upgrades, and much more to keep them at the cutting edge until the 2040s. That is, until the F-47 can take over in numbers.