Raytheon’s latest iteration of its now-proven AN/APG-82 radar is the APG-82(V)X, unveiled today and intended to provide additional capabilities for the F-15EX Eagle II. The next generation of the APG-82 is based around gallium nitride (GaN) technology, reflecting a growing trend in advanced radars.
The APG-82(V)X was announced today at the Air, Space & Cyber Conference in National Harbor, Maryland, where TWZ spoke to Christopher Short, director, requirements and capabilities at Raytheon’s radio-frequency solutions division.
Following on from the APG-82(V)1 as used in the current F-15E Strike Eagle and F-15EX, and which you can read about in our previous deep-dive on the topic, Raytheon is now marketing the APG-82(V)X. Short says this is the company’s long-term proposal for the radar in the Eagle II for both the U.S. Air Force and international customers.
The new GaN array is central to the improved capabilities of the APG-82(V)X. Compared with previous technology, GaN generates less heat and has the capacity to operate at higher voltages, meaning that output power can be increased, while component size can be reduced. More generally, using GaN helps ensure that radars can be smaller, lighter, and have lower power demands than equivalent-performing radars.
According to Short, drawing from the same amount of power, GaN ensures the radar is not only more efficient, but also gives increased range. The radar also has a new processor, which Short explains gives it “increased processing speed, which gives us more air-to-air, more air-to-ground, and better electronic warfare capabilities.” Added to that is a new power unit, but the end result has the same form, fit, and function as the earlier radar, so it can fit in a standard F-15EX, just like the current array.
Short says that the company developed the APG-82(V)X on the basis of recommendations from the U.S. Air Force, including from Gen. Mark D. Kelly, the chief of Air Combat Command. One of the observations from the customer was that the F-15 has, in recent years, been “relegated a little bit to standoff,” meaning that it’s increasingly expected to fight at greater distances from the threat.
This is a move that has also been driven by the increased ranges that air-to-air missiles are now achieving, as you can read about here in the case of the AIM-120 Advanced Medium-Range Air-to-Air Missile (AMRAAM). This will only become more important once its AIM-260 successor approaches operational service, and there is potentially a host of other long-range air-to-air missiles waiting in the wings. In addition, enemy aircraft and missiles are getting more advanced with longer reach, and the F-15EX is not a low-observable (stealthy) fighter. As a result, it would need to operate at greater distances from some threats in certain circumstances. So a more capable radar paired with more capable missiles will not only make it more lethal, but also make it far more survivable.
The Air Force’s recommendations led Raytheon to address the question of how to get more range out of the radar, with GaN technology being the answer. In fact, as Short explains, the radar array is actually a little bit bigger than in the APG-82(V)1, too, which also helps achieve greater reach.
“Now we’re trying to keep up with the AMRAAM boys and give them the radar capability they need for those long-range missiles,” Short told TWZ. The AIM-120 continues to extend its reach, with the longest shot ever taken occurring recently from an F-22.
Another Air Force pointer for what it was looking for in future fighter radars was low probability of intercept (LPI), a capability that is meanwhile baked into the radars of stealthy aircraft, like the AN/APG-77 in the F-22 Raptor and AN/APG-83 in the F-35. LPI modes leverage various tactics, like frequency hopping and utilizing a wider swath of the electromagnetic spectrum, to make it harder for the enemy to detect their emissions, especially in terms of reliably geolocating their source.
According to Short, Gen. Kelly was also convinced that, while the Air Force is “really good in X band, we’ve got to get out of [it].” X-band is used in most fire-control radars and is thus the biggest threat that enemies are attuned to ‘listen’ for.
As Short explains: “I no longer live in that band where the adversary looks for me the most often. That agility is key to being low probability of intercept and low probability of detection.”
Having done that for the APG-82(V)X, the result is “a significant capability, especially when it comes to electronic warfare, with a more agile ability to deal with a peer ally in Russia or in the Pacific.”
Essentially, compared to previous radars, the APG-82(V)X makes the host fighter harder to find, in terms of electronic protection, and in the electronic warfare realm, it gives the F-15EX crew more tools to address more threats.
The APG-82(V)X is also designed to be paired with the F-15EX’s Eagle Passive/Active Warning Survivability System, or EPAWSS, a very powerful radar warning and electronic warfare suite, which also continues to be improved. An AESA’s rapid and very powerful and narrow beam scanning capabilities gives it very potent, albeit in many cases latent, electronic attack capabilities.
As Short explains, the combination of the APG-82(V)X and its LPI with EPAWSS should ensure that the F-15EX is able to survive in a stand-in fight, as well. “That’s the capability we want to bring to both the United States Air Force and to our international partners,” Short says.
Another argument for the APG-82(V)X is the fact that, by now, the APG-82(V)1 is starting to show its age, having first been installed in the F-15E under the Radar Modernization Program (RMP). Noteworthy is the fact that the APG-82(V)1 ported technology across from the APG-63(V)3, used in upgraded F-15C/Ds, and the APG-79, as found on the F/A-18E/F Super Hornet.
“It’s a great radar, but it’s older technology, and technology has advanced, and parts are harder to come by,” Short says. “We have supply challenges daily, and so instead of making expensive replacements to give you the same capability, what we’re doing is upgrading, and so when we replace that processor, we’re now going to have more capability.”
While the APG-82(V)1 cannot be upgraded to APG-82(V)X standard, Short confirms that “parts and pieces” of the new radar can be added to the older one. For example, the older radar could be fitted with the new processor from the APG-82(V)X, with the GaN array being fitted further down the line.
Short says that the development of the APG-82(V)X has benefited from work the company has done on radar technology for sixth-generation applications, although he declined to give more details beyond the fact that “we’ve done a lot of work on next-gen radar, and we’ve taken some of the things we’ve learned from that and brought it back to fourth gen, and so we’ve reduced some risk, both on the array and on the processor. We know this isn’t starting from scratch.”
So far, the APG-82(V)X hasn’t been flight-tested and is still being developed at El Segundo, California.
However, Short says the company is confident that it can now go to the customer and say, “This is a follow-up to the (V)1, this is the next iteration, and a whole different world of fire-control radar for a fourth-gen fighter.”
Should the U.S. Air Force and other customers opt for the APG-82(V)X, the new radar should ensure that the F-15EX is able to get the most out of longer-reaching missiles in standoff engagements, as well as operate in more contested stand-in scenarios.
Contact the author: thomas@thewarzone.com