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Before his retirement in October, the U.S. Air Force intelligence chief, Lt. Gen. Dave Deptula, forcefully argued that the Air Force should be preparing to fly the F-35 Joint Strike Fighter as an intelligence collector, a requirement that does not formally exist for the stealthy multirole plane now in testing. If the Air Force intelligence community decides to continue with Deptula's push, it will need to convince a reluctant Air Combat Command (ACC) that adding an ISR role won't require adding new equipment to the already delayed aircraft or distract from the F-35's primary combat roles.
"The devil is in the details," said Mason McLean, the senior requirements analyst in ACC's intelligence directorate.
The F-35s are designed to strike targets deep inside heavily defended airspace, and to do that, each will carry a moving-target-indicator and imaging radar, plus electro-optical and infrared video cameras. These sensors were installed mainly to track targets for pilots, but Deptula argues they could double as ISR sensors by feeding video or electronic readings into the Air Force intelligence network called the Distributed Common Ground System.
The F-35s, and for that matter the F-22s currently in the Air Force fleet, "need to be thought of not just as fighters, but as integrated flying ISR sensor nodes with an additional capability to engage adversaries if necessary. We may in fact value them more for their ability to penetrate denied airspace, collect adversary information and then distribute it to decision-makers, than the traditional notion of a fighter," Deptula said in an interview shortly before his retirement.
The Air Force historically has purchased certain planes for striking targets or winning air superiority — the operational missions — and others for gathering intelligence. The service's Predator and Reaper unmanned planes, which can carry both missiles and cameras, have started to break down that bifurcation, and Deptula wants the trend to continue.
"My motivation is to move the U.S. Air Force away from the traditional segregation of operations and intel to the integration of operations and intel," Deptula said.
But the military's requirements process, which for the Air Force begins at ACC, is too cumbersome and is making it harder than it needs to be to fly F-35s in ISR roles, Deptula said.
ACC SAYS ‘PONY UP'
ACC officials said they have good reason to think carefully before embracing a formal ISR role for the F-35. The intelligence community has to define exactly what kind of information is required by a specific class of end-user and how quickly, McLean said. Those requirements must be balanced with cost and technical feasibility. In addition, the F-35's sensor suite could generate terabytes of data, far more than is possible to record, much less downlink in real-time. Therefore, the language of exactly what is needed by the intelligence community must be precise, he said.
Questions abound: Does the intelligence community want raw data, or is the fused data used by the war-fighting community enough? Does the intelligence community require data in real time or can some of the information be recorded onboard the F-35 until it lands?
An Air Force requirements official who asked not to be named said there are technical reasons to be leery. The F-35 would have to be modified to carry out ISR tasking in conjunction with its combat role, which creates a risk of negatively affecting the aircraft's primary missions, the official said.
The unnamed official gave an example of the service's concern: "If we're designed to 100 percent to do the [suppression of enemy air defenses/destruction of enemy air defenses] mission, for example, and then if someone were to suggest we do the ISR mission while we're doing that, we're going to have to redesign and you can assume we're going to lose some capability in the primary mission," the official said.
The unnamed official also called for more details about the proposal that would be required from the ISR side. "The intel community needs to step up and say, ‘This is what we'd like.' It's been a little bit difficult to identify any particular organization within that nebulous community," the official said.
"Who'd we bring this capability for? Is it the [Combined Air Operations Center]? Is it for the intel community at the [Defense Department] level? The national level? Those questions, I'm not sure have been asked, let alone answered, by the intel community," the ACC requirements official said. "The intel community is going to have to pony up to make sure that data we get from our sensors, that we can port it to somewhere they can process it."
If ACC were to examine an ISR role, experts would conduct a formal mission decomposition. "We get the experts in a room and we just tear it apart for a couple of weeks to get into the minutiae of how a particular mission would be done. That is done to generate requirements for the systems onboard that ultimately gets us that capability. That has not been done for ISR [mission for the F-35]," the unnamed official said.
FUSION POWER
For Deptula, the ACC view represents the type or thinking he tried to move the Air Force away from during his tenure. He said flying the planes in an ISR role could be done without adding more equipment. "The F-35 can be tasked for an ISR mission just like F-16s with recce pods in Iraq are being tasked today," he said.
Technology is "breaking the old stovepipes of how we used to view the traditional roles of fighter, bomber or ISR aircraft," he said, "Today's technology enables mission capability on individual aircraft that we never dreamed of when aircraft mission designators were established." In the case of the F-22 and F-35, much of the information gathered is transparent to the pilot because the data from the aircraft's sensor suite is "fused."
Fused data means that from the pilot's perspective, he sees a display that correlates all of the disparate information from the radar, cameras and electronic warfare equipment into a single coherent picture. "In the past, you had a bunch of functions that a pilot would have to deal with for separate missions. Technologies now allow much of the information collection to be transparent to the pilot. So it can be programmed to collect and disseminate appropriate information without the pilot doing a whole lot of anything," Deptula said. The fused avionics afford the F-35 the ability to collect, analyze, transmit, and share "decision quality" information with those who need it, he said.
For the ISR mission, a sticking point is how to get data from the aircraft to the analysts who will use that information. "The DCGS is the logical system to take this information and distribute to all the components," Deptula said. The question is the communications method the planes would use. Other fighter aircraft feed information into DCGS using their Link 16 data link antennas, but the Air Force does not want to use those when the F-35 is in hostile territory because Link 16's transmissions could give away the plane's position. Link 16 also has limited bandwidth.
F-35s will be able to share data with each other, and eventually the F-22 Raptor air superiority fighter and B-2 stealth bomber, via Multi-Function Advanced Data-links (MADLs), which are higher bandwidth data links designed to be more difficult to detect. The F-35s also will retain Link 16 devices for communicating in friendly airspace. The aircraft will also have the ability to share data via the Mobile User Objective System, a forthcoming satellite communications network.
For the Air Force and the other services involved, the ISR problem for the F-35 arises from the fact that the aircraft straddles two joint capability areas: battlespace awareness, which is the domain of aircraft such as the E-3 Sentry and the E-8 Joint Surveillance Target Attack Radar System aircraft, and force application, which is the domain of fighters such as the F-16 or F-15, said McLean of the ACC Intelligence Directorate.
It is precisely these "stovepipes" that Deptula said he is trying to do away with. "My motivation is to move the U.S. Air Force away from the traditional segregation of operations and intel to the integration of operations and intel," he said.
KEY TECHNOLOGIES
McLean acknowledges the F-35's potential as an ISR collector as a "no-brainer" largely because of where it will fly. "The biggest thing that a fifth-generation jet, whether it's an F-22 or F-35, brings is access in an anti-access environment," McLean said, referring to areas defended by high performance enemy fighters such as the Russian Su-35 and advanced surface-to-air missiles. "Because of their low observable characteristics, they can get in there amongst the threats and be survivable, that allows them to gather data where no one else can," he said.
To gather data inside enemy airspace, the F-35 possesses a vast array of sensors, which includes radar, infrared cameras and electronic warfare equipment. Further, the avionics on the F-35 are superior to those found on previous fourth-generation fighters like the F-15, F-16 or F/A-18, McLean said.
"The fifth-generation jets have really good sensors. That goes without question," he added. In some respects, the sensors on the F-35 will exceed those of the F-22 Raptor. However, the F-22's advantage is that it flies "at near twice the altitude and 50 percent greater airspeed than the F-35," Deptula said. The F-35 will typically operate at speeds of around Mach 0.95 at 30,000 feet, while the Raptor can cruise at altitudes above 50,000 feet at speeds of about Mach 1.8, or nearly 1,200 mph.
One of the key technologies behind the F-35 is the Northrop Grumman AN/APG-81 radar, which is an active electronically scanned array radar. This radar consists of about 1,000 transmit/receiver modules and can simultaneously run air-to-air and air-to-surface modes. The radar also has both a synthetic aperture radar mode, which creates black and white photo-quality images of the ground, and a ground moving target indicator mode for tracking moving vehicles. Further, it can interweave the synthetic aperture radar picture with the ground moving target indictor mode, allowing the pilot to view the image as a complete whole.
"This is something we have to do with several separate aircraft and a ground station today. The F-35 puts this capability in the hands of every F-35 aircraft the joint force commander employs," Deptula said.
There are also two separate infrared camera systems onboard the F-35. The AN/AAQ-37 Distributed Aperture System consists of six infrared cameras placed around the fuselage of the F-35. Working together, the cameras create a 360-degree spherical image that can be viewed in the pilot's helmet-mounted display. The cameras provide the pilot with an infrared image equivalent to roughly 20/20 human vision, said Dave Jeffreys, Lockheed Martin's senior manager for F-35 Improvements and Derivatives. Additionally, these cameras also provide the pilot with missile warning, cueing of air and surface targets, and air-to-air situational awareness, Deptula said.
The second infrared camera type is the Lockheed Martin AN/AAQ-40 Electro-optical Targeting System, which is similar to the Sniper targeting pod mounted on the F-16 but is carried in an internal mounting in the F-35's nose, Jeffreys said. The camera provides very high-resolution video with a continuous zoom feature, which would be useful during nontraditional ISR missions in support of ground troops, he said. The camera will also provide the F-35 with long-range passive air-to-air search and track abilities.
Rounding out the F-35's sensor suite is the AN/ASQ-239 electronic warfare system. Based on the F-22 Raptor's AN/ALR-94 suite, the AN/ASQ-239 is many times more sensitive than previous generations of radar warning receivers, Jeffreys said. Whereas older equipment might be able to narrow down the direction of enemy radar to roughly a quadrant, the F-35's AN/ASQ-239 can precisely locate the direction of the threat, he said.
For Deptula, the U.S. has a chance to take advantage of the efficiencies that would come with flying numerous kinds of sensors on one type of aircraft. "Think of how many different aircraft we would have to acquire to perform all of these tasks if we did them separately?" he said. "That's why fifth-generation systems are so important — they aren't just fighters anymore, they're F-B-A-EA-E-RF-AWACS 22s and 35s information/action nodes in an airborne network of seamless sensors and shooters." å
