The Need for a Sixth Generation Fighter:
Four factors have guided the decision to begin work on the F/A-XX and F-X programs: increasingly sophisticated anti-access threats, the potential compromise of key F-35 program details to China, the age and finite quantity of existing air superiority/air dominance platforms in conjunction with the proliferation of foreign fifth generation aircraft, and industrial base concerns,
In 2001, Lockheed Martin's X-35 was selected to be developed into the F-35. As of 2015, the planned initial operational capability (IOC) dates for the F-35 are 2015 for the Marines, 2016 for the Air Force, and 2018 for the Navy. The significant delay in the development of the F-35 program has enabled US competitors, chiefly China and Russia, to start to develop technologies that would limit the effectiveness of the F-35's low observability. The proliferation of very high frequency (VHF) radars is a cause for concern, the F-35's air frame is optimized to perform against X and S band radars. As per the Raleigh scattering region, electromagnetic radiation will scatter from bodies smaller than its wavelength (Plopsky & Bozzato, 2014). However, VHF radars are not a panacea type solution to countering stealth aircraft.
Historically, VHF radars have been of limited use as the resolution cells are too large too provide a target quality track for weapons systems unlike the X and S bands (Majumdar, 2014). China and Russia have recently applied advances in processing power to improve the quality of their VHF systems. For example, the Type 052D Luyang III destroyer features a Type 518 L-band radar paired with a conventional Type 346 AESA radar which could provide it with nascent anti-stealth capability against aircraft like the F-22A and F-35. At the present level of technological maturity, VHF systems would likely provide an early warning capability against stealth aircraft and could eventually cue X and S band systems to provide targeting information. However, the weapon employment range of a VHF radar cued with a X and S band system may not be tactically significant. In the future, a system of VHF radars could be networked via a high speed datalink, the resolution cell could be refined enough for a weapon quality track (Majumdar, 2014). But the US has made preparations to keep the F-35 relevant in highly contested VHF anti-access area denial (A2/AD) environments into the 2030s and beyond.
Another factor that has led to the development of a sixth generation fighter stems from China's cyber espionage activities. Edward Snowden recently released documents confirming China's role in stealing F-35 program information including the AN/APG-81 design, engine schematics, infrared signature reduction methods, etc. (Gady, 2015). These technical details have not only helped China build its own stealth aircraft, but also the information could be used to potentially facilitate the creation of countermeasures against the F-35. Lockheed Martin insists China has not managed to obtain the "crown jewels." Despite Lockheed Martin's assurances, the data breach is generally regarded as a significant setback for the F-35 program. Chief of Naval Operations (CNO) Admiral Jonathan Greenert recently remarked, "The losing of proprietary data on high technology from cleared defense contractors — it’s just driving me crazy."
"Senior officials are in the preliminary stages of examining options should stealth—one of the F-35’s key attributes—be compromised by new technology. The idea is to be able to hand off to the next presidential administration both a healthy F-35 program, and other options should the next president find the aircraft’s technology outdated. The hope is the F-35’s technology will be viable for decades to come." - Amy Butler, 2015
The emergence of a new threat during the development of a fighter program is not new. The development of the sixth generation F-X while the fifth generation F-35 has yet to enter service is not dissimilar from how the Advance Tactical Fighter (ATF) program, which eventually led to the fifth generation F-22, was undertaken while the fourth generation F-X program - which led to the F-15A, had only just concluded. US reconnaissance satellites captured images of the T10-1 prototype, the Soviet's fourth generation response to the F-15 which resulted in the Su-27, in 1977 (Goebel, 2014). The Soviets had responded more quickly than anticipated and it was apparent that a new fighter was needed to maintain the US' technological advantage prompting the the ATF in 1981.
The consolidation of the US aerospace and defense industry after the Cold War has only been exacerbated in recent years due. Instead of a diverse set of multiple smaller procurement programs, there are only four major combat aircraft procurement programs over the next decade (UCLASS, T-X, LRS-B, and some F/A-XX and F-X work). Thus, if a major defense contractor fails to secure one of these programs it will be unable to sustain its aircraft manufacturing capability. Part of the justification for accelerating the F-X and F/A-XX programs is to provide work for the defense industrial base such that further consolidation can be avoided (Sweetman, Asker, Norris, & Butler, 2015).
The last major reason for starting development of a sixth generation fighter, at least from the Air Force's perspective, is the limited number of high end air superiority platforms currently in service. F-22 production was prematurely terminated with 195 aircraft produced of which only 186 are in the Air Force's current inventory. Of these 186 aircraft,
at any one time with the remainder of the aircraft serving in either in an attrition reserve, training, or test and evaluation role. The F-15C/D fleet will now receive
to keep the Eagle fleet operational until at least the late 2020s. While the F-35 will provide robust air to air capabilities, it is not an air dominance fighter like the F-22. The US will require new sixth generation air superiority aircraft in the 2030s to retain the current disparity in projected kill ratios for US fighters.
A new sixth generation air superiority fighter is needed in the 2030s to hedge against a decline in expected US exchange ratios against increasingly advanced Russian and Chinese aircraft.
Similarly, while the F-35 is capable as a strike fighter in terms of air-to-air capabilities it is not a purpose built air dominance platform like the F-22. In an Australian Parliamentary hearing within the Foreign Affairs, Defense And Trade Joint Committee, Garry Liberson who is the Technical Lead of Operations Analysis and Strategic Studies at Lockheed Martin indicated the F-35 would have a six to one exchange ratio against "advanced red threats" in the 2015 to 2020 time frame (Source 69, page 5).The red threats described by Mr. Liberson are likely to be either upgraded Su-30s or Su-35s. Thus the author would surmise the F-35 would perform less favorably against the J-20 and Pak Fa when compared to the F-22 as discussed above.
The A2/AD Strategic Environment of 2030:
It is important to emphasize the context in which American sixth generation aircraft will operate in conjunction with other American and allied aircraft rather than merely analyzing various tactical air to air combat scenarios between individual adversary and US platforms. The sixth generation development programs take place within the broader context of the third offset strategy and new concepts like distributed lethality all of which are geared towards mitigating advancements made by Russia and China to limit US power projection operations.
To provide a brief overview, China began to develop systems to inhibit US power projection after the overwhelming victory of the United States in the Persian Gulf War:
"...the consensus that U.S. forces were unbeatable in a conventional force-on-force conflict became the dominant global lesson learned. As the previous study notes [Conduct of the Persian Gulf War], 'while the Vietnam syndrome might always have been exaggerated and misinterpreted, the display of U.S. power in the Persian Gulf had the effect of creating an image of overwhelming power'. For nations, non-state actors, and other entities opposed to U.S. influence and contemplating violent means toward achieving their international political aims, conventional warfare seemed almost a closed option." - Tangredi, pg.29, 2013
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