Image 1: F-22 test aircraft firing a AIM-9 X Block II missile
As Part I discussed, the F-22 is largely a product of late 1980s Cold War requirements and doctrines. However, the F-22's unmatched air-to-air capabilities make it relevant to the Pacific more than 20 years after the creation of the original Advanced Tactical Fighter (ATF) program requirements but lingering issues as a result of new technology and new objectives remain undressed with the current F-22A fleet. The USAF plans to spend $11.7 billion on F-22 upgrade programs through 2020. The entire combat coded F-22 fleet of 143 aircraft (including backup inventory airframes) will be upgraded to the Block 35 standard incorporating the latest increment 3.2B upgrades. The combination of the increment 3.1, 3.2A, and 3.2B upgrade programs will greatly enhance the F-22's ability to effectively engage expected air-to-air and air-to-ground threats from near peer to peer level adversaries over the next two decades. Each upgrade will be thoroughly examined before the aggregate effect of these upgrades on USAF capabilities is discussed in subsequent articles.
Image 2: Since 2004, requirements for specific capabilities within the increment series of upgrades have frequently changed over time. For example, increment 3.2B included an auto-GCAS system but it was subsequently removed. Image Credit: Government Accountability Office, 2012
Increment 3.1 - Block 30 Standard Airframes
Image 3: F-22A with increment 3.1 upgrade
The increment 3.1 upgrade adds significant destruction of enemy air defense (DEAD) capabilities to the Raptor and is the process of being fielded with all 149 aircraft will receive increment 3.1 by 2016 (GAO, 2012). The main elements of increment 3.1 include: synthetic aperture radar (SAR) modes to the AN/APG-77, electronic attack capabilities, geo-location of electro-magnetic emitters, and GBU-39 Small-Diameter Bomb (SDB I) integration (Defense Industry Daily, 2013). Block 30 and Block 35 aircraft will receive increment 3.1 upgrades for a total of 149 F-22A's with increment 3.1 capabilities (Carlisle, 2011). The combination of increment 3.1 capabilities makes the F-22 arguably the most capable DEAD asset within the USAF.
A four-ship of Increment 3.1 aircraft can successfully find, fix, track, target and engage targets in the most challenging of anti-access environments...Stealth and speed, combined with an advanced electronic attack capability, allow pilots to operate with impunity while achieving their mission objectives. - Lt Colonel Paul Moga, 2012
Increment 3.1 capabilities will prove to be invaluable in dismantling hostile integrated air-defense systems (IADS) on a large scale, especially in the Pacific. The PRC is procuring increasingly capable arsenal of surface-to-air missile (SAM) systems such as the HQ-9, S-300 and possibly the
S-400. The F-22's exceptionally small radar cross section (rcs) coupled with geo-location and GBU-39 capability makes the aircraft uniquely suited to cost effectively counter SAM systems. The minimum safe distance between a stealth aircraft and a radar site is usually determined by the aircraft's rear rcs, which is almost always larger than the frontal rcs, as the aircraft has to turn around to head back to base or pursue a new target. In the case of the F-22A, the frontal rcs is between 0.0001m^2 and 0.0002m^2 while the rear rcs is between .01-.001m^2 (Global Security & Kopp, 2012). The S-400 uses the 92N2E "Grave Stone" AESA engagement radar which would detect the F-22's rear rcs between 40 to 30 nautical miles away as shown on the Air Power Australia image below. The GBU-39 has a maximum stand off range of 60 nautical miles which would enable the F-22 destroy S-400 sites with impunity (Boeing, 2013).
Image 4: Detection ranges for Russian SAM engagement radars. The 92N2E is arguably the most capable X-band SAM radar developed outside of the United States or Europe. The HT-233 PESA engagement radar used by the HQ-9 system is a derivative of the Russian 30N6E1 Tomb Stone (Kopp, 2014).
Block 35 Standard Airframes- Increment 3.2A & 3.2B
Increment 3.2A
Arguably one of the most significant shortcoming of the current F-22 fleet is its limited compatibility with other systems in terms of communication and data-link capabilities. The F-22 is currently equipped with the minimally detectable intra-flight datalink (IFTL) to share information between other F-22's. The use of conventional data links and communication systems could betray the location of the aircraft to hostile forces equipped with emission locator systems such as the Chinese CETC YLC-20. However, IFTL can only transmit information between F-22s and not to other assets such as the F-35 or F-15. When IFTL was originally designed, this was a perfectly acceptable as the USAF was originally going to replace its entire F-15C and F-15E inventory with 750 F-22A's.
The F-22 was designed to communicate covertly, only with other F-22s , using the intra-flight datalink (IFDL). Today, the thought of developing a stovepiped system seems unfathomable. But in the 1980s, designers envisioned a massive force of hundreds of F-22s that would maintain stealth in hostile airspace in part by not emitting communications that could be detected. These aircraft would handle the frontline mission of destroying enemy air defenses and establishing air superiority behind hostile lines in an air campaign by communicating only with one another over the IFDL. The original F-22 designers never envisioned the need for the fighter to communicate with legacy fighters, because what was thought to be hundreds of F-22s would be combined with the F-35 to constitute the combat Air Force of the future after older models retired. - Amy Butler, 2013
Image 7: Operation Western Zephyr. Image Credit: USAF, 2013.
With such a limited force of F-22's, Raptor pilots urgently need to be able to operate seamlessly with older 4th generation aircraft and the F-35. The current fleet of F-22's can receive Link-16 data but cannot transmit via Link-16 and the data it does receive through Link-16 is not fused with information from its on board sensors (Majumdar, 2012). The limits of the F-22's compatibility with other systems were fully apparent in Operation Western Zephyr conducted in 2013. Raptor pilots had to resort to communicating through unsecured radio channels to British Eurofighter pilots as they were unable to communicate though Link-16 (Axe, 2013). Without increment 3.2A, the USAF has fielded a number of interim solutions such as the Battlefield Airborne Communications Node (BACN) which has been fitted to a few RQ-4 Global Hawk and heavily modified BD-700 Global Express aircraft (E-11). BACN effectively translates incompatible communication systems:
[BACN] provides a high-speed, Internet protocol (IP)-based airborne network infrastructure that that extends communications ranges, bridges between radio frequencies, and “translates” among incompatible communications systems – including both tactical and civil cellular systems. Using BACN, a Special Forces soldier on the ground could use a civil cell phone to speak to a fighter pilot in the cockpit. - Defense Industry Daily, 2014
Image 8: BACN payload on board an E-11 aircraft.
While BACN allows the F-22 to communicate in the short term, the USAF possess a limited number of BACN equiped aircraft. Increment 3.2A will serve as a suitable long-term solution as it grants the F-22 two-way Link-16 capabilities and integrates received Link-16 data with on board sensors.
Because sensor fusion does not ‘read’ Link-16 tracks for own-ship solutions, the Raptor will display two tracks – one is own-ship derived from sensor fusion, the other is the Link-16 track – for the same given target,” Getgood says. 'The pilot can declutter the scope should he chose to view only own-ship tracks to reduce pilot workload.' The Inc 3.2A upgrade fixes that by seamlessly correlating all of the data coming in via the Link-16 with the F-22’s other sensors and datalinks. 'What Increment 3.2A does is that it allows sensor fusion to bring information from those tracks into the solution – it provides just one track now with that data supply' - Majumdar, 2012.
While the Link-16 system will allow the F-22 to operate effectively alongside fourth generation aircraft, the system is not considered to be a low-probability-intercept system like the multifunction airborne data link (MADL). Until recently, increment 3.2A included provisions to install MADL into the F-22 airframe which would allow it to safely communicate to F-35 aircraft in anti-access environments (Trimble, 2010). The USAF was correct in its decision to choose Link-16 capability over MADL integration for the F-22 given the low number of F-35 aircraft being fielded in the short term (increment 3.2A will be fielded from 2014 to 2016). Furthermore, Link-16 would enable the F-22 to communicate with a much greater range of aircraft including the F-35. However, the lack of LPI in Link-16 is a significant drawback especially if the F-22 is operating in a hostile anti-access environment. Lockheed Martin is currently in the process of working with L-3 Communications to develop a minimally detectable method to allow the F-22 to communicate through Link-16 under "Project Missouri":
The company [Lockheed Martin] recently showcased a new datalink capability for the fighters through Project Missouri, a proprietary program. Lockheed validated the use of a Link 16 transmit capability from the twin-engine F-22 Raptor as well as showcased a waveform developed by L-3 Communications and optimized for low-probability-of-intercept/low-probability-of-detection transmissions (LPI/LPD)...The trials required the use of an Air Force Raptor as well as the F-35 Cooperative Avionics Testbed (CATbird), a 737-based flying laboratory that is used to test F-35 software standing in as a Joint Strike Fighter surrogate. The F-22 was able to transmit to a Link 16 terminal on the ground. - Amy Butler, 2014
The Air Force does not currently have a requirement for a LPI waveform integration for the F-22 but such a capability would prove to be very convenient. Although the main element to increment 3.2A is Link-16 capability, increment 3.2A will also increase the F-22's electronic protection measures as well as adding new combat identification and targeting capabilities (GAO, 2012).
The increment 3.2B largely focuses on increasing the F-22's air-to-air capabilities and will be fielded between 2017 and 2020. The upgrade allows the F-22 to utilize the AIM-120D, AIM-9X Block I, and AIM-9X Block II missiles as well as adding improved IFTL capabilities, improved geo-location capabilities, and enhanced electronic protection features (GAO, 2012). At the moment, the F-22 is limited to using older versions of the USAF's main radar guided and IR guided missiles, the AIM-120C-7 and the AIM-9M missiles respectively.
The AIM-120 Advanced Medium-Range Air-to-Air Missile (AMRAM) is the F-22's main air-to-air weapon and enables the F-22 to engage targets a beyond visual range. In air superiority missions, the F-22 typically carries six AMRAM's which are carried by LAU-142/A pneudraulic hydraulic launchers in its main weapon bay. The latest variant of the AMRAM, the AIM-120D, offers a host of improvements over the current AIM-120C-7 including a two-way data link, high angle off-bore sight capability, global position system-enhanced Inertial Measurement Unit, expanded no escape zone, and 50% greater range (Office of the Under Secretary of Defense, 2012). Although the F-22 is currently capable of firing an AIM-120D as of Update 4 to the Raptor fleet, without the new hardware from increment 3.2B the F-22 will be unable to make use of the AIM-120D's data-link.
Image 10: AIM-9X Block II
The inclusion of the AIM-9X Block I & Block II will significantly increase the F-22's within visual range combat capabilities. The AIM-9X Block I is already in use with 4th generation aircraft such as the F-15 and F-16 but it has yet to be fielded on the F-22. The Block I includes a thrust vectoring engine nozzle, improved flare rejecting IR seeker, autopilot, and a new digital processor (Defense Industry Daily, 2014). The combination of these features enables the AIM-9X Block I to preform off-bore sight shots (capable of helmetless high off-boresight shots) and intercept highly agile targets. Block II further improves upon the Block I design:
The 2-way datalink is the most significant single Block II change, as it allows the missile to fly toward targets its seeker can’t yet see, using target position tracking from its fighter. Improved seeker lock-on-after-launch and re-acquisition makes the missile harder to evade, and the new ‘lofting’ fly-out profile boosts the Block II enough to give it some capabilities beyond visual range. - Defense Industry Daily, 2014
Although increment 3.2B will not be fielded on Raptor units until 2017, the USAF will be able use some of the AIM-9X Block II's capabilities by 2015 due to
Update 5 software:
In an effort to get the missile to operational units quickly, the USAF is essentially jury-rigging the AIM-9X on to the F-22. The current aircraft stores management system will recognize the missile as an AIM-9X, but the USAF could not change the missile launch engagement zone displays on the jet given in the time available given the forthcoming ESMS installation. 'A pilot can shoot that as a 9X, however, the aircraft systems, as far as the pilot vehicle interface and things like that display targeting information, will be as if it were a 9M'...Pilots will have the flight envelope to launch the AIM-9X at higher angles-of-attack as well as the ability to cue the missile to its expanded field of view compared to the AIM-9M. What they will lack are the in-cockpit displays, which reflect the increased range and maneuverability of the new weapon. That means that operational testers will have to develop 'rules of thumb' for when frontline pilots should decide to launch the missile. - Dave Majumdar, 2012
The Lock on after launch (LOAL) feature of the Block II will help reduce the potential draw backs stemming from the LAU-141/A trapeze system utilized on the F-22's side weapon bays. The process of opening the side weapon bay doors and launching the AIM-9 from the trapeze system takes several seconds longer to preform when compared to launching an AIM-9 from a conventional wing mounted pylon. In a dogfight, a few seconds can be crucial. With LOAL, the F-22 can preemptively launch the Block II before acquiring the target to expedite the process.
Image 11: AIM-9M-9 mounted on a LAU-141/A hydraulic launcher. From Global Security: "This launcher, which uses some components from the existing LAU-128/A launcher, is basically the wingtip launch rail from an F-16 with a swing out mechanism that extends rapidly. The LAU-141/A is also fitted with a missile motor plume deflector, which prevents damage to the side weapons bay as the missile launches off the rail. Each missile is loaded by opening the doors, extending the rail, sliding it on the rail, retracting the missile, and closing the doors."
Even with the full 3.2B hardware and software modifications,
the F-22 will not be able to make full use of the Block II's capabilities without a helmet mounted display like the joint helmet mounted cueing system JHMCS or the Scorpion system. The USAF originally planned to integrate the Scorpion HMD system with the F-22 but the program was cancelled as a result of sequestration (more info about HMD's in Part V).
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