In pursuit of a multirole mission, the F-35’s designers accepted trade-offs that reduced its stealth performance in exchange for significant improvements elsewhere.
The US military has two stealth fighter options: the F-22 Raptor and the F-35 Lightning II. While both aircraft are generally lumped together as fifth-generation stealth fighters, each has different stealth characteristics with respect to radar cross section (RCS), infrared (IR) signature, acoustic and visual signature, and electronic emissions (EMCON). Which aircraft’s stealth technology is better than the other?
In most respects, there is a clear answer. The F-22 outperforms the F-35 with regard to its radar cross section, especially from head-on aspects and against X-band radar. The F-35 is still stealthy, to be sure, but the aircraft is optimized more for survivability in contested airspace rather than air dominance. Specifically, the F-35 made concessions for multirole performance, maintainability, and cost, which negatively affected its RCS performance. The F-22, meanwhile, was designed from the ground up to optimize air superiority—requiring it to stay as invisible as possible against the X-band radar used in most adversary fighters. To optimize the F-22’s RCS, designers incorporated angular faceting and carefully canted surfaces and angles, internal weapons bays, and RAM coatings.
The F-22 also has superior infrared stealth performance. The F-22 features a flat, shielded thrust-vectoring nozzle, reducing IR and shielding engine hot spots from ground-based sensors. The F-35, meanwhile, uses an exposed circular nozzle, which lacks shielding. The F-35 does incorporate advanced heat sinks and ducts, which reduce the IR signature—but not to the F-22’s levels. The result is that the F-35 is more susceptible to advanced IRST systems.
The F-22 is also quieter than the F-35. The reason for this is relatively straightforward: the F-35 is especially loud, even by the standards of a fighter jet. Powered by a Pratt & Whitney F135 engine, the fifth-generation fighter is notably loud on takeoff and at low altitudes. The F-22, meanwhile, has features designed to reduce the acoustic signature, including serrated engine nozzle edges and acoustic baffling. Also, because the F-22 can supercruise—achieving supersonic speeds without the need for afterburners—the F-22 is quieter at high speeds than the F-35.
The F-22 has a lower visual signature. Designed to be compact and non-reflective, the F-22 is harder to detect visually. The F-35 isn’t necessarily glaring to the naked eye, but the bulkier fuselage, built to accommodate greater internal fuel and a multi-role payload, has a larger canopy that increases visual contrast.
Finally, the F-22 also has superior EMCON performance. Designed to adhere to strict EMCON protocols, the F-22 only transmits radar and other emissions when absolutely necessary. The onboard AESA radar (AN/APG-77) has low probability of intercept modes and frequency agility. The F-35, on the other hand, is renowned for its network connectivity—but that connectivity requires constant emissions from the MADL, DAS, and EOTS. And while these emissions are encrypted and unlikely to be intercepted, they’re more active and detectable from an EMCON perspective.
So, what does this all mean? Ultimately, the F-22 is the better stealth performer in contested airspace with near-peer adversaries. In pursuit of a multirole mission, the F-35’s designers accepted trade-offs that reduced its stealth performance in exchange for significant improvements in sensor fusion, mission systems, and interoperability. So the F-22 is stealthier, but the F-35 is generally more versatile—and still plenty stealthy on its own.
About the Author: Harrison Kass
Harrison Kass is a defense and national security writer with over 1,000 total pieces on issues involving global affairs. An attorney, pilot, guitarist, and minor pro hockey player, Harrison joined the US Air Force as a Pilot Trainee but was medically discharged. Harrison holds a BA from Lake Forest College, a JD from the University of Oregon, and an MA from New York University. Harrison listens to Dokken.
Image: Wikimedia Commons.
