ORLANDO, Fla.—The same virtual test environment used to complete operational testing for the F-35 is now driving the “best F-35 trainer in the world” and is about to be replicated from a single site in southern Maryland to five “super sites” around the nation.
The Air Force and Navy are pouring billions into the Joint Simulation Environment to expand the system from its starting point at the Naval Air Warfare Center Aircraft Division, Patuxent Naval Air Station, Md., to far larger installations at Nellis Air Force Base, Nev.; Edwards Air Force Base, Calif.; and Joint Base Elmendorf-Richardson, Alaska.
Longer term, the Air Force plans to have JSE sites at all its F-35 bases, including Hill, Luke, Eglin, Eielson, Davis-Monthan, and other National Guard sites, and overseas bases like RAF Lakenheath in the U.K., said Derek Greer, integrated battlespace simulation and test department head at the Naval Air Warfare Center Aircraft Division (NAWCAD). “We are working with the Air Force and the Navy to get at least an eight-ship of F-35 and manned Red Air at all of these sites,” he said.
Stripped down versions are now at sea on aircraft carriers. Lacking the full-scale simulators at Patuxent River, they still have features that have helped deployed fighter squadrons maintain certain skills in environments where they would not otherwise be able to practice them. All that is possible because of the precise way the simulators mimic the actual flight software.
“JSE was born out of the need to get F-35 through operational test,” said Greer, who led off a panel discussion on JSE at the Interservice/Industry Training and Simulation Conference on Dec. 3. “We did not have the threat density, nor the threat complexity at our open-air ranges to fully stress and evaluate the F-35, so the decision was made long ago that we needed to do a chunk of the F-35 operational test program in a simulator. … In partnership with the Air Force, we built the facility at Pax River to do exactly that.”
In fiscal 2024, 820 F-35 pilots used the JSE trainers at Patuxent River, including Pacific Air Forces squadrons stationed at Eielson Air Force Base, Alaska; RAF Lakenheath; and the Air Force Weapons School at Nellis, Greer said.
Now the Air Force and Navy are working together to scale the system far beyond its original purpose, an ambitious effort that will draw on both military and industry expertise. Col. Matt Ryan, simulators division chief and senior materiel leader for the Air Force Life Cycle Management Center, said scaling the program to become the joint-force training asset envisioned will take years and extensive effort.
Yet the payoff for the effort will be huge: as the number of locations increases, so will the number of pilots that can leverage this training.
“We’re trying to take something that was meant for a single purpose at a single place, almost for a single point in time, and scale that out to be used at many places, for all time, for almost all people,” he said, speaking at the same I/ITSEC briefing. “That’s a pretty significant scaling challenge. It certainly means that the original design as we knew it, even just two or three years ago is probably not going to be sufficient moving ahead. So we spent the last year doing some work to do some re-architecting … so that we can turn it into a scalable solution that deploys well to multiple sites.”
The Nellis site will be a major site for the Air Force, as will the Edwards site, with a lot of validation and developmental test activities. But the primary focus will be mission rehearsal, large force exercises, unit-level training, and continued operational test. “We see other use cases as far as experimentation and potentially developmental tests in the future, but all centered around real-time mission-level operations,” Ryan said.
The F-35 is the only fighter supported in JSE today, but F-22 is in the works he said. Other functions and features could be developed to add space data and, potentially, to make JSE useful to Space Force users, Ryan said.
Funded by the F-35 Joint Program Office, JSE starts with a series of “F-35-in-a-Box” simulators built by F-35 prime contractor Lockheed Martin. The simulators are a full re-hosting of the underlying operational flight program software used in the actual jet, so precise it can be used for operational test and evaluation—and therefore ideal for training, because it is such a precise representation.
The fighter simulator links to a government-owned software integration stack, which incorporates digital models mimicking the performance of U.S. weapons and, even more important, leveraging the latest classified intelligence data to precisely imitate the performance parameters of adversary aircraft and weapons.
That means pilots can using JSE trainers to face the exact threats they would face in combat—including not just kinetic threats, but precisely modeled electromagnetic spectrum effects that take into account clouds, terrain, wind, and other factors.
The level of control, speed, and repetition possible makes JSE not only effective, Greer said, but also highly cost-effective, especially for training in complex multiaircraft operations.
“When we start talking eight-ship training, the Red Air picture, the ground picture—simply getting eight airplanes off the ground for training—you’re talking a very challenging logistical,” Greer said. “Then if we think about what the right air picture would be against that eight ship, it could be eight vs. eight, eight vs. 12, eight vs. 16, 20, whatever. It is very expensive proposition to fly, and fly repeatedly, to get our pilots the reps and sets needed to really become excellent with a tactic. But in JSE, we’re able to do eight, 10, even 12 missions per day. That’s eight vs. 20, 12 times in a day. It is really more than any one squadron can handle.”
JSE is a mission trainer; it does not replicate live-flight performance training and is not a substitute for time spent physically flying the airplane. But the F-35’s capabilities are such that some tactics and procedures and some functionality cannot be leveraged on training ranges because doing so could givie away secrets to potential adversaries. This is where JSE is valuable: providing the ability to run through scenarios repeatedly until pilots are highly skilled in those procedures, Greer said.
“From an affordability perspective, getting those reps and sets in in the simulator, where we don’t need to pay for a lot of gas, we’re not putting all those hours on the engines, it is a huge dividend,” Greer said. And just as importantly, he added, “we’re able to replicate the threat very, very actively—probably more accurately than we can in the open-air range.”
That includes intelligence-derived models for red air, ground, and surface-to-air missile threats. JSE includes the Air Force-developed Virtual Airborne Threat System, which enables red force operators to simulate adversary pilots flying against blue-force operators.
“That has really changed the fidelity, really the ball game in terms of presenting a complicated air picture to our blue fighters,” Greer said. “Having fifth-gen blue fighters actually man red-air cockpits, and bring that maneuverability, has brought our realism to an all-time high.”
One key to the realism is new software called GRID, a high-speed engine that crunches the math to mimic the propagation and performance of radio frequency, infrared, and other signals, accounting for external factors—clouds, mountains, other aircraft—as well as tactical choices, such as angle of attack, angle of depression, and so on, all in real-time.