The F-35 Isn't Just 'Stealthy': Here's How Its Electronic Warfare System Gives It An Edge
In addition to a stealthy design that absorbs and deflects radar energy, the F-35 has an advanced electronic warfare system. Ten radar warning sensors are distributed around the airframe, as are infrared cameras for detecting heat-generating threats.
The F-35 fighter is the enabler of American air dominance through mid-century. It will provide the Air Force, Navy and Marine Corps with combat aircraft that can survive in places where no legacy fighters would be safe, collect information crucial to joint operations, and suppress threats that might otherwise preclude victory.
Despite the program’s importance, though, many politicians, pundits and even some senior military officers don’t understand key features of the F-35. For example, although the fighter is frequently described as “stealthy”—invisible to detection or tracking by radar and other sensors—public reference is seldom made to its electronic warfare capabilities.
That’s understandable, because release of details about the F-35 electronic warfare (EW) system is carefully controlled. However, it is the synergy of an integrated stealth design with the world’s most advanced EW architecture that makes F-35 the most survivable combat aircraft ever built. So you can’t fully understand the F-35 value proposition unless you have some grasp of the plane’s electronic warfare capabilities.
I have business ties of one sort or another to several of the biggest contractors involved in the F-35 program including airframe integrator Lockheed Martin, engine provider Pratt & Whitney, and electronic warfare lead BAE Systems. And yet, two decades after the fighter was first conceived, I can count on the fingers of one hand the number of times I have ever had a serious conversation about the on-board EW suite. The industry team doesn’t like to talk about it in public, and neither does the government.
So what follows comes from other sources, all of them available to the public if people are willing to dig. Let’s begin with a description of what electronic warfare is all about. Among the handful of elemental forces that define our universe, electromagnetic energy has proven to be by far the most malleable in human hands. Electromagnetic energy is often said to be arrayed in a spectrum ranging from forms with the lowest frequencies (vibrations per second) and longest wavelengths to those with the highest frequencies and shortest wavelengths.
There are no obvious boundaries in this continuum, but the properties of electromagnetic energy gradually change as frequencies increase and wavelengths decrease. The two most useful segments of the EM spectrum for warfighters are the infrared region of frequencies just below the visible light range, and the radio wave frequencies of longer wavelength than infrared. As this description implies, radio waves and infrared energy are invisible to the human eye, but they can be readily detected and manipulated using a variety of technologies.
That is what electronic warfare was conceived to do. Long before the Pentagon designated the electromagnetic spectrum as a warfighting “domain,” military planners had figured out that if they could exploit the properties of radio and infrared waves while denying spectrum access to enemies, they would gain important operational advantages. For instance, by overloading relevant frequencies with energy, they could prevent enemy communications and radars from functioning effectively, and disrupt the homing sensors on heat-seeking missiles (which operate at infrared frequencies).
However, there are problems with this strategy. If you generate enough energy to “jam” hostile communications, you might disrupt friendly transmissions—or become a beacon to your enemies. So electronic warfare isn’t just about pumping out a lot of energy, it’s about managing how that energy is used while disguising your location and intent. The F-35 fighter is by far the most advanced expression of this science ever devised, because it must reconcile the generation of diverse signals with the requirement to remain stealthy and continuously utilize other on-board systems such as digital datalinks.
The only way to make all of these functions operate in harmony was to create an integrated architecture in which all of the key features of the airframe were closely coupled. That architecture differs greatly from the looser, “federated” architectures of last-generation fighters, because those aircraft were not designed to be stealthy. Once you decide you want to be invisible to enemy radar and other sensors, though, every emission your plane generates has to be carefully controlled. So even the turbofan engine on the F-35 is designed to limit its reflectivity to radar and the heat of its exhaust.
The core of the F-35’s electronic warfare system is the AN/ASQ-239 EW suite, a modular system providing both defensive and offensive capabilities ranging from detection of hostile emitters to geolocation of threats to the automated release of countermeasures—either infrared flares or radar-reflecting chaff. The system provides continuous, precise monitoring of threat frequencies in all directions, fusing and displaying relevant information inside the visor of the high-tech helmet worn by the plane’s pilot. It not only will prioritize solutions to a threat, but it can respond without any action by the pilot.
The system also can assimilate information from various offboard sources including other F35s via a variety of secure datalinks, so that a pilot has comprehensive awareness of where hostile and friendly forces are in his or her vicinity. In fact, F-35 collects so much information in so many frequencies and wavelengths that it is often described by users as a sponge—soaking up everything in its operating area worth knowing.
Because the F-35 is highly integrated, it isn’t so easy to describe where the EW system ends and other parts on the electronic architecture start. Everything gets channeled through a central processor that sorts out diverse inputs at the rate of a trillion operations per second, and then the most appropriate on-board systems are used to address threats as needed. For instance, a “distributed aperture system” of six infrared cameras scattered around the airframe might detect surface-to-air missile launches originating from a particular location, leading to a pilot’s decision not only to dispense flares but also jam radars in the same area using the fighter’s multi-function radar.
Executing that kind of complicated response from a legacy fighter would take precious time, and might not be feasible at all given design limitations. Moreover, a legacy fighter would lack the advantage of an integrated stealth design, making it much more vulnerable even with EW upgrades. No aircraft can be invisible in every electromagnetic frequency, but the F-35 is designed to be so hard to detect in the frequencies used by targeting radars that an enemy would need to be nearly within visible range to even attempt a kill (very few enemies would be able to get that close without being shot down).
There are many arcane features of the F-35 EW system that I don’t have space to describe here, such as the towed decoy that distracts incoming missiles and the digital library that stores details about all known threats. Suffice it to say that when you take into account all the electronic features of the F-35 fighter and then combine them with the stealth qualities of engine and airframe, you end up with an invincible combat aircraft piloted by an operator with unprecedented situational awareness. This is why F-35s typically kill over 20 adversary aircraft for every friendly loss in exercises aimed at honing pilot skills.