Testing the Combat Edge

Mark Ayton visits Edwards Air Force Base, California, where a few good people are making the F-22 Raptor even more combat capable

F-22 RAPTOR

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F-22 91-4009/ED releases a GBU-31 JDAM; the first airto- surface weapon cleared for operational use on the Raptor.

Glossy magazine features about the F-22 Raptor tend to focus on the combat-coded wings and their operations in the continental United States and overseas.

Not this one.

Like all other combat types in the US Air Force inventory, the F-22 has a System Program Office (SPO) based at Wright- Patterson Air Force Base near Dayton, Ohio. The Ohio-based F-22 SPO directs developmental test (DT) and operational test (OT) through two major commands: Air Force Materiel Command and Air Combat Command respectively. F-22 OT is undertaken by the 422nd Test and Evaluation Squadron based at Nellis Air Force Base, Nevada.

F-22 DT is the mission of the rarely reported on 411th Flight Test Squadron (FLTS), based at Edwards Air Force Base home of the Air Force Test Center.

The 411th FLTS has been involved with the F-22 since September 1990 when it conducted the official Department of Defense fly-off for the then Advanced Tactical Fighter program between the Lockheed YF-22 and Northrop YF-23 prototypes. No prize for identifying the winner of that competition.

In February 1998, the 411th FLTS accepted F-22 Engineering, Manufacturing and Development (EMD) aircraft 91-4001 on to its books. That aeroplane, delivered to Edwards by a C-5 Galaxy, was the first of nine EMD aircraft used for the F-22 DT programme completed in December 2004.

Since Christmas of that year, the 411th has undertaken all subsequent DT test events required by the SPO. At the end of 2016, the squadron’s bread and butter work, some of its most exciting yet, certainly in terms of the aircraft’s increased capabilities, is testing the latest F-22 hardware and software introduced on the Raptor under Increment 3.2B.

Raptor Upgrades

When the F-22 was given its initial operational capability declaration in December 2005, the first combat-coded Raptors were assigned to Air Combat Command’s 27th Fighter Squadron ‘Fighting Eagles’ based at Langley Air Force Base, Virginia.

Back in the early 2000s, weapon system programmes, including the F-22 Raptor, were upgraded under a system called spiral development. Under the Raptor’s original modernisation programme, the first upgrade was dubbed – no kidding – Spiral 2. By the mid-2000s, US Department of Defense policy changed on the F-22, after which subsequent major combat capability upgrades were called increments and all sub-set changes are called updates. Today, as was the case at the time of the policy change, an update is a fix to an existing problem.

Spiral 2 introduced the capability to deliver a Joint Direct Attack Munition supersonically.

Increment 3.1, the first major combat capability operational flight programme (OFP) upgrade, introduced new sensor tasking. No one from the Edwards-based F-22 Combined Test Force (CTF) would discuss specifics of Increment 3.1. Based on information from the FY2012, FY2013, FY2014 and FY2015 Annual Reports by the US Department of Defense’s Director, Operational Test and Evaluation Increment 3.1 provides enhanced air-to-ground capability including geo-location of selected emitters, electronic attack, and air-to-ground Synthetic Aperture Radar (SAR) mapping, which gives the F-22 pilot the ability to selfdesignate a target using a SAR map.

Another part of 3.1 was the introduction of an electronic attack capability for the Northrop Grumman APG-77 active electronically scanned array multimode, multitarget interleaved search/track, all-weather fire-control radar.

Increment 3.1 also included integration of the GBU-39 small-diameter bomb, a mediumrange stand-off glide weapon.

F-22 capabilities outlined in this feature were reported in the FY2012, FY2013, FY2014 and FY2015 Annual Reports by the Department of Defense’s Director, Operational Test and Evaluation, and were in no way confirmed or denied by the 411th FLTS or 412th Test Wing.

The 411th started testing Increment 3.1 in 2009; the first upgraded aircraft field by the US Air Force was Block 30 F-22 06-4115 assigned to the 525th Fighter Squadron based at Elmendorf Air Force Base, Alaska, in March 2012.

Air Combat Command’s F-22 capability requirements list required further improvements to such an extent that Increment 3.2, the follow-on OFP, was so extensive the F-22 SPO opted for two phases: Increment 3.2A and Increment 3.2B.

Increment 3.2A, fielded in August 2015, involved further changes to the aircraft’s EW system, communication and identification capabilities, using the Joint Tactical Information Display System (JTIDS) in receiveonly mode and fusing the JTIDS’s feed to the main cockpit display. In general, and not specific to the F-22, a JTIDS feed provides voice, navigation, positioning and target identification data in a jam-resistant digital format. Prior to development of Increment 3.2A, the Raptor’s JTIDS feed was displayed independently from sensor-fused data.

Increment 3.2A added the military grid reference system (MGRS). This was introduced in response to an operational request from Air Combat Command to meet the needs of F-22 operations over Iraq and Syria; the system is already being used in combat.

Lockheed Martin’s F-22 Chief Test Pilot Steve Rainey said: “MGRS is important for interoperability of ground forces and aircraft providing air support. The US Army uses MGRS to direct fire support on to a target. Prior to 3.2A Update 5.2 we didn’t have MGRS in the F-22 because it was not designed to be a close air support aircraft, and we used lat-longs for targeting. MGRS simply allows us to use the same coordinate system used by coalition ground forces without the need to translate between MGRS and lat-longs.

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F-22 91-4009/ED releases four GBU-39 test vehicles over the Pacific Sea Test Range off the coast of southern California. This was the first four-bomb ripple release of GBU-39s undertaken as part of the Increment 3.2A test programme.
David Henry/F-22 Combined Test Force

Integration of MGRS is the one of the most recent requests received from Air Combat Command to date.”

Major Lee Bryant, Director of Operations, 411th FLTS, added: “The success for the F-22 programme was the quick turnaround response. From the point when we received the MGRS test plan, we were able to conduct it within a short space of time and field it to the units downrange. The MGRS was successfully used by F-22s in combat for the first time in the summer of 2016.”

Steve Rainey continued: “It’s a big deal because MGRS was a new, relatively small and easy capability addition that has significant impact for combat air forces and was developed, tested, and fielded in a short time, in response to requirements from the field.”

Major Bryant further added: “A JTAC [Joint Terminal Attack Controller] can pull MGRS coordinates from his map and communicates them to the F-22 pilot for input into the weapon’s guidance.”

The MGRS is a kilometre-based worldwide grid reference system designed to pinpoint geospatial points. When an MGRS-generated coordinate is received, the pilot is able to use the data without the need to convert the information into a lat-long position appropriate for entering into the weapon’s guidance system. Conversion can potentially delay the kill chain.

n the past, battle space information received via JTIDS was rated as substandard, compared to the information generated by the F-22’s own sensors. Now the F-22’s mission system validates the quality of the JTIDS data received and only fuses validated data into the display, which is beneficial and important for targeting.

Increment 3.2B

As with Increment 3.1, no one from the Edwards-based F-22 CTF would discuss specifics about Increment 3.2B.

According to a 2014 Department of Defense Select Acquisition Board report, Increment 3.2B integrates AIM- 9X Sidewinder Block II and AIM-120D AMRAAM, further improves the electronic protection (EP) capability over Increment 3.2A, enhances the F-22’s geolocation capability from the Increment 3.1 baseline with the addition of Geolocation 2, integrates the enhanced stores management system (ESMS, see later), which is required to integrate any new weapon on the F-22 beyond Increment 3.1, improves the intra-flight datalink (IFDL) with greater bandwidth to enable cooperative functions required to realise Increment 3.2B candidates.

In terms of software, Increment 3.2B includes the development, certification and integration of a new OFP to ensure system interoperability and performance of all increment-level or upgrade developments.

F-22 capabilities outlined in this feature were also reported in the FY2012, FY2013, FY2014 and FY2015 Annual Reports by the Department of Defense’s Director, Operational Test and Evaluation, and were in no way confirmed or denied by the 411th FLTS or 412th Test Wing.

The Edwards-based F-22 Combined Test Force (CTF), which includes the 411th FLTS, is conducting full-up testing of Increment 3.2B to assess the upgrade using operationally significant ground and flight test scenarios to identify performance deficiencies.

Discussing Increment 3.2B, Steve Rainey said the latest OFP adds a lot of new avionics radar functionality, full functionality of the AIM-9X Sidewinder (3.2A provided partial functionality) and integration of the AIM-120D AMRAAM missile.

Testing software and hardware in Increment 3.2B is the biggest part of the 411th’s current test workload.

Software testing involves not only evaluation of the new capabilities, but also concurrent regression testing of existing capabilities, while the hardware testing for a new missile includes the usual mix of weapons integration events: structures, loads, captive carriage, separation and live fire of the AIM-9X Sidewinder and AIM-120D AMRAAM.

Under 3.2B the F-22 has a new enhanced stores management system simply called ESMS, a requirement needed for the aircraft to keep pace with increased data throughput.

Details of the ESMS were not provided by the F-22 CTF, but AIR International understands the system monitors and controls launchers, weapon bay doors and weapons, prioritises dispensation of countermeasures, and controls emergency jettison of stores.

Continuing the discussion about 3.2B improvements, Rainey and Bryant understandably declined to discuss improvements being made to the avionics and APG-77 radar capabilities.

In mid-August, the US Air Force made the milestone C decision for Increment 3.2B. Milestone C gives the go-ahead for low-rate initial production. The decision-makers had enough confidence in the testing completed to date to go into low-rate initial production. Major Bryant explained how the decision is based on the assessment of technical risk: “Is the test programme sufficiently mature to proceed to actually start building components?”

The 411th FLTS has four F-22s assigned: three Block 10 aircraft (91-4006, 91-4007 and 91-4009) and one Block 30 jet (07-4132). Blocks indicate the hardware configuration of the aircraft at the time it was rolled out of the factory at Marietta, Georgia. Updates and increments require the original hardware configuration to be changed on the modification line, which is now located at a purpose-built facility at Hill Air Force Base, Utah.

All four of the 411th’s aircraft are configured to Increment 3.2B standard and will be used for the remaining nine months of the test campaign.

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The 411th Flight Test Squadron is currently conducting missile launches of the Dmodel of the AIM-120 AMRAAM missile as part of the Increment 3.2B test programme.
Matthew Short/F-22 Combine Test Force

Missile Tests

The 411th FLTS first conducted structures testing of the AIM-9X in 2009 as part of the flight sciences portion of the Increment 3.2A DT test programme. Structures was followed by loads and separations testing. By comparison the AIM-120D, introduced with 3.2B, has no loads testing requirement because the missile has the same fit and form as the earlier AIM-120C-series already fielded on the F-22. The 411th launched the first AIM-120D in 2015 and has completed six to date. Major Bryant said 411th flight test engineers devote a lot of effort to ensure a new missile like the AIM-120D is fielded to the Combat Air Forces in the cheapest way possible. This is achieved by minimising the number of missiles launched: “Firing a missile is one of the most expensive tests we perform, [so] our test procedures seek to test everything we can before firing a missile. Actual missile shots are the validation and verification events for all of the data collected up until that point. The test process itself is structured so the high-dollar shots are the last events undertaken in each test programme.”

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The AIM-9 Sidewinder air-to-air missile has been carried by F-22s since the type’s initial operational capability declaration in December 2005. Today the 411th Flight Test Squadron is testing the AIM-9X version which features jet vane control.
Jonathan Case/F-22 Combined Test Force

Steve Rainey: “If some objectives that also achieve some of the OT objectives can be accomplished in a DT-orientated, instrumented manner, we try to include them into the DT test programme. It’s a structured and well-thought-out approach amongst the DT and OT test teams.”

Directives

Speaking about the organisation of the F-22 CTF and whom the respective components take their directives from, Steve Rainey explained its joint nature: “The original CTF director Lt Col Al Kohn (Retired) was here recently. He started what we call the purple suit team. We’ve had CTFs for years, but Al’s vision was to have one test team that was transparent. He referred to the personnel as purple suits [purple signifying a joint organisation].

“That said, there are certain functions, as a contractor, I’m not allowed to sign – for example, flight authorisation, which is an air force function. As the contractor, Lockheed Martin maintains the aircraft, so all of the changes made to each aircraft’s configuration have to be signed off by me. But from the big team perspective, if somebody wants to know something about flying test missions, they can, for example, ask Major Bryant or me. It doesn’t matter what colour suit you wear, who you work for, we have one objective: to make sure the combat air forces have the best F-22s possible.”

Test tasking is decided by the F-22 SPO based on Air Combat Command’s requirements. The SPO forms contracts for each increment or update with Lockheed Martin and Boeing. Using Increment 3.2B as an example, the contract dictated what capabilities were to be in 3.2B.

Once the contract is in place, developers and the DT test team then decide what’s required to test the capabilities, validate all of the work and write the test plan.

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Seven F-22 Raptors parked on the 411th Flight Test Squadron flight line on August 10, 2016. Interestingly, the aircraft third in from the camera, F-22 07-4132/ED, is shown with an external weapon load comprising a single AIM-9X Sidewinder and a single AIM-120D AMRAAM carried on a guided missile launcher fitted to the left wing underwing pylon.
Christian Turner/US Air Force

This has to be vetted by a technical review board from the 412th Test Wing, the test organisation based at Edwards. Once the test plan has passed its review, as part of test mission planning, the F-22 test pilots and flight test engineers review all of the safety issues involved before the test plan is vetted by a safety review board. The review board comprises members of the F-22 SPO, Lockheed Martin and the Air Force Test Center, the owner of the 412th Test Wing, which in turn owns the test processes and procedures that allow the 411th FLTS to fly.

Steve Rainey continued: “Once the test plan and the safety plan are approved, CTF engineers meet regularly to decide on the style and approach of the flight testing. Flight testing proposals are then discussed in detail during scheduling meetings, where direction is given by either myself or Major Bryant.”

Performance

Having witnessed a number of highperformance take-offs by F-22s at Edwards, all of which were very impressive to watch, the author asked Major Bryant and Steve Rainey why these took place. Both pilots smiled and jokingly said: “Because it’s fun.” No kidding, but there are reasons for performance take-offs, as Steve Rainey explained: “When we conduct a functional check flight [FCF] in the F-16, we perform a quick climb to get into the ejection envelope as quickly as possible: a position from where you can either eject quickly in a safe mode so you get more than one swing, or you can get the aircraft to a base key position from where you might be able to land as quickly as possible after an engine failure on take off. Typically, we don’t do that in the F-22, because there is so much thrust on the aeroplane that if you lose an engine it’s not a dire emergency and the jet can safely be recovered with a single engine.”

Steve also explained one type of departure that’s possible but not cleared at Edwards due to noise restrictions: “The F-22 has a supersonic optimum climb profile to get you to altitude in the absolute fastest way possible and with the most range, so if you were launching against an inbound threat that’s the profile you’d want to use. The profile puts you supersonic very shortly after the end of the runway.”

The discussion moved to the types of manoeuvres only seen by the public during an F-22 demonstration flown by the Air Combat Command demo pilot. Each year when Air Combat Command’s new F-22 demo pilot comes on board, the pilot receives a training session in the Lockheed Martin simulator at Fort Worth specifically to experience every aspect of how the aircraft flies and to cover some emergencies.

He said the F-16 has critical action procedures that the pilot has to memorise because there may not be time to refer to a checklist in the event of an in-flight emergency: “There is no bold face in the F-22, no critical action procedures, because it pretty much takes care of you; but there are a couple of emergencies that only come about if the aircraft is close to the ground and an engine fails. The demo pilot needs to see each emergency once, so I put him through the training and show him the steps required in the unlikely event of such an emergency.”

Hand-in-hand

The 411th FLTS works closely with Air Combat Command’s OT squadron, the 422nd TES based at Nellis. All new software sets undergo a safety of test certification with the 411th as early as possible, so the 422nd can load and operate at least one of its F-22s with the update. This helps the F-22 programme in a number of ways, as Major Bryant explained: “When the 411th conducts flight testing, the test process is conducted in accordance with a detailed and scripted test plan that tells us what to look for. Remember we look at the minutiae; the detail to ensure everything is fitting together well. Once we’ve cleared the new software for safety of flight, the 422nd can fly it in a more operational representative way, and sometimes find faults and issues by virtue of flying the aircraft. OT pilots highlight any issue they find and notify the programme. Then DT will test the fault or issue with one of the 411th’s instrumented aircraft to try and get more data on the specific fault.

“Operational testers can conduct some test events during the DT phase. Bringing them in early to participate in test missions already paid for by the 411th allows them to gather some of their data requirements, which reduces the cost of the OT programme.”

Cooperation between the two units goes further. A US Air Force Test Pilot School (TPS) graduate is assigned to Nellis to help integrate DT-OT test efforts. When an issue is identified during DT testing, especially one deemed as significant for the OT test programme, the pilot assigned to Nellis is able to perform additional and more scripted flight tests and highlight the problem to the 422nd on site. In a bestcase scenario, the process can lead to a fix before the product reaches the OT testers. A cleaner product should reduce the length of the OT test programme.