Sixth-generation jet fighter

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A 1:1 mock-up of the FCAS at the Paris Air Show 2019. It depicts the New Generation Fighter as well as one of its smaller, unmanned "loyal wingmen."

A sixth-generation jet fighter is a conceptualized class of fighter aircraft design more advanced than the fifth-generation jet fighters that are currently in service and development. Several countries have announced the development of a sixth-generation aircraft program, including the United States, China, United Kingdom, India, Russia, Italy, Sweden, Japan, Germany, Spain, Taiwan and France.

The United States Air Force (USAF) and United States Navy (USN) are anticipated to field their first sixth-generation fighters in 2025–2030.[1] The USAF is pursuing development and acquisition of a sixth-generation fighter through the Penetrating Counter Air[2] to replace its existing air superiority aircraft such as the McDonnell Douglas F-15 Eagle and complement existing platforms in service such as the Lockheed Martin F-22 Raptor. The USN is pursuing a similar program called the Next Generation Air Dominance, likewise intended to complement the smaller Lockheed F-35 and replace its existing aircraft such as the Boeing F/A-18E/F Super Hornet.[3]

However, with very little reporting on progress on sixth-generation fighters, slippage being reported in production of variants of the fifth-generation fighters like the F-35, and timelines for aircraft in development like the F/A-XX Program being delayed, 2030–2035 is a more realistic timeframe for fielding sixth-generation fighters.[4]

Common design elements[edit]

While at an early stage of development several distinct characteristics common to nearly all nations' sixth-generation fighter concepts have emerged.

  • More modular design going beyond wing hardpoints with primary aircraft components able to be swapped out within hours to optimize for the mission requirements and easing the introduction of future upgrades.
  • Single-seat-only cockpits with training occurring mostly in simulators.
  • Optionally manned with the same airframe capable of conducting remote controlled or AI-controlled missions.
  • Controlling a swarm of drones acting in both a defensive and reconnaissance role for the controlling fighter.
  • Battlefield data fusion with the aircraft acting as a network node capable of receiving and relaying data to multiple other platforms such as other aircraft, ground vehicles or satellites and processing that data onboard to dynamically generate new target lists or update mission parameters on the fly.
  • Increased-range stand off weapons with the drones conducting reconnaissance within enemy airspace and supplying targeting data to the fighter which remains safely outside enemy airspace.
  • Greater electrical power generation to enable equipping directed-energy weapons such as a laser CIWS.
  • Virtual cockpit helmet-mounted display allowing the pilot 360-degree vision and doing away with cockpit displays.

Development by region[edit]

Asia[edit]

Mainland China[edit]

People's Liberation Army has reportedly begun development on a 6th generation fighter. In 2019, important breakthroughs in design and development of several key components, including a next-generation engine were announced. China plans to field it in the 2025–2030 time frame.[5][6]

India[edit]

The Indian Air Force (IAF) formally announced plans to develop sixth generation combat systems during the Air Force Day on 8 October 2020. The IAF chief stated that the system will have "directed energy weapons, smart wingman concept, optionally manned combat platforms, swarm drones, hypersonic weapons" and other equipment.[7][8] The IAF chief told OnManorama that they have a "clear roadmap" for sixth generation fighters and the "planning process" is ongoing.[9]

Taiwan[edit]

In the wake of threat of invasion by the People's Liberation Army,[10] ROC(Taiwan) Ministry of Defense re-initiated development of next generation jet fighters. Nearly 30 years after the first flight of F-CK-1 Fighter, T-5 Trainer becomes the first step of ROC(Taiwan) Air Force developing 6th-gen fighter that wishes to balance the cross straight air superiority.[11]

Japan[edit]

In 2010, the Japanese Ministry of Defense exposed the concept of sixth-generation national product jet fighter, the i3 FIGHTER.[12] This would be based on the 3I concepts of an aircraft that was Informed, Intelligent and Instantaneous.[13] On March 22, 2016, Japan conducted the first flight of the Mitsubishi X-2 Shinshin testbed aircraft for this project.

Europe[edit]

France, Germany and Spain[edit]

France has abandoned any attempt to develop an indigenous fifth-generation fighter and has moved resources directly to development of a sixth-generation fighter aircraft.[14]

In July 2017 France and Germany announced they would jointly develop a new combat European New Generation Aircraft to replace the Eurofighter Typhoon, Panavia Tornado and Dassault Rafale fighters.[15]

The German Air Force, in partnership with Airbus Defence and Space, are in the initial stages of developing a new sixth-generation fighter. Sharing the same name as an earlier British UCAV project, the German Future Combat Air System (FCAS) is a separate program, expected to be operational in the 2030–40s. Little is currently known about the project, other than it will likely be a twin-seat "system of systems" aircraft acting as a combat platform as well as controlling UCAVs.[16]

Spain announced in December 2018 that it will join the project.[17]

Russia[edit]

On 26 August 2013, Russia revealed it would proceed with development of a sixth-generation jet fighter. They say the aircraft will most likely be pilotless. However, they would not skip completing development of fifth-generation fighter projects, like the Sukhoi Su-57.[18]

The Mikoyan MiG-41 is a sixth-generation jet fighter interceptor aircraft currently being developed by Mikoyan.[19][20] The project which started in 2019, and if purchased by the Russian Air Force, the first production of MiG-41 could be completed in 2025,[21] to enter service after 2027.[22]

United Kingdom, Sweden and Italy[edit]

In July 2014, Jane's Information Group reported that a House of Commons Defence Select Committee had published a report about the UK's future "post-2030 combat aviation force structure". The report highlighted a possibility of the UK committing to a next generation fighter program to potentially replace the Eurofighter Typhoon post-2030; the Eurofighter Typhoon has since had its intended service life extended to around 2040.[23]

In July 2018, British Secretary of State for Defence Gavin Wiliamson unveiled the UK's Combat Air Strategy and announced the development of a sixth-generation fighter concept named the Tempest for the Royal Air Force at Farnborough Airshow 2018.[24][25]

In 2019, Sweden and Italy joined the project.[26][27]

In 2019, India and Japan were also invited to join the project.[28][29]

North America[edit]

United States[edit]

History[edit]

In October 2012, Under Secretary of Defense for Acquisition and Sustainment Frank Kendall III stated in a memo, "It is not too early to begin consideration of the next generation of capability that will someday complement and eventually replace the F-35."[30]

In April 2013, DARPA started a study to try to bridge the USAF and USN concepts.[31]

The Pentagon 2015 budget request has studies to lead to an acquisition program in fiscal year 2018.[32]

Frank Kendall revealed that funding for initial sixth generation fighter development would be requested in the FY 2016 budget. Next-generation fighter efforts will initially be led by DARPA under the "Air Dominance Initiative" to develop prototype X-planes. The agency as well as industry are known to have started internal research on potential sixth generation technologies for several years. Kendall confirmed that Navy and Air Force will each have variants focused on their mission requirements.[33]

In 2016 the USAF announced a change of course to pursue "a network of integrated systems disaggregated across multiple platforms" rather than a "sixth generation fighter" in its Air Superiority 2030 plan.[34]

On September 14, 2020, the USAF announced that a prototype aircraft part of the Next-Generation Air Dominance program had flown for the first time at the Air Force Foundation's Air, Space, and Cyber Conference. The details remain highly classified. There are no available details about the plane's first flight date and location or capabilities. Additionally, there is no available information on who the manufacturer of the aircraft is.[35]

Design concepts[edit]

Dubbed the "Next Generation Tactical Aircraft"/"Next Gen TACAIR", the USAF seeks a fighter with "enhanced capabilities in areas such as reach, persistence, survivability, net-centricity, situational awareness, human-system integration and weapons effects," a November 4, 2010 presolicitation notice states. “The future system will have to counter adversaries equipped with next generation advanced electronic attack, sophisticated integrated air defense systems, passive detection, integrated self-protection, directed energy weapons, and cyber attack capabilities. It must be able to operate in the anti-access/area-denial environment that will exist in the 2030–2050 timeframe.”[36][37]

The sixth-generation fighters are expected to use advanced engines such as Adaptive Versatile Engine Technology to allow longer ranges and higher performance. Risk reduction began in 2012 so that engine development can start around 2020. An engine is to be ready when fighters are introduced by the Navy in 2028 and the Air Force in 2032.[38]

USAF General Mike Hostage has said that they have yet to decide on which features will define the sixth-generation fighters.[39]

In November 2013, the Air Force Research Laboratory released a request for information (RFI) for a laser weapon that could be mounted on next-generation air dominance fighters by the 2030s. The Air Force is interested in three categories of lasers: low-power for illuminating, tracking, targeting, and defeating enemy sensors; moderate-power for protection to destroy incoming missiles; and high-power to offensively engage enemy aircraft and ground targets. The laser and systems controls are to work at altitudes from sea level to 65,000 ft at speeds from Mach 0.6 to Mach 2.5. Laser submissions are to be at technology readiness level 4 (basic components work in a lab) by October 2014, and the Air Force wants a system to be at technology readiness level 5 (system components work in a simulated environment) or higher by 2022. The RFI requests submissions with detailed descriptions in a militarily useful configuration, potential problems and solutions, and cost estimates.[40]

The RAND Corporation has recommended that the U.S. military services avoid joint programs for the development of the design of a sixth-generation fighter. Studies by RAND have found that in previous joint programs, different service-specific requirements for complex programs have led to design compromises that raise costs far more than normal single-service programs. In a comparison between four recent joint service programs (F-35, Joint Strike Fighter, T-6A Texan II Joint Primary Aircraft Training System, E-8 JSTARS, V-22 Osprey) and four recent single-service programs (C-17 Globemaster III, F/A-18E/F Super Hornet, F-22 Raptor, T-45 Goshawk), costs for joint programs rose 65 percent nine years after a Milestone B decision to move into engineering and manufacturing development compared to 24 percent for independent programs during the same timespan.[41]

Engine development for sixth generation fighters is already underway to be more efficient in making jets faster and giving them a longer range. While current engines operate best at a single point in the flight envelope, newer engines could vary their bypass ratios for optimum efficiency at any speed or altitude. That would give an aircraft a much greater range, faster acceleration, and greater subsonic cruise efficiency. A variable cycle engine could configure itself to act like a turbojet at supersonic speeds, while performing like a high-bypass turbofan for efficient cruising at slower speeds; the ability to supercruise may not be a critical requirement, but it will likely be able to with this engine type. One critical component is the adaptive fan to allow the engine to vary its bypass ratio depending on altitude and speed with a third stream of air to increase or decrease the bypass ratio. A low-bypass configuration would be used for take offs and supersonic flight, and a high-bypass configuration would have high propulsive efficiency for cruising. The U.S. Navy and Air Force have different sixth generation fighter development programs, but both services are working together on engine development. The Air Force is aiming for a Milestone A decision by 2018, with a production version to be ready possibly by 2021. Companies involved with next-generation engine development include General Electric and Pratt & Whitney.[42]

On 30 July 2014, General Mike Hostage spoke about the evolving nature of proposed sixth-generation fighter requirements at an event hosted by the Air Force Association (AFA). Since Air Combat Command released a request for information (RFI) in 2009 for industry feedback on sixth-generation air dominance technologies, teams thinking of requirements have been told not to think in terms of a "platform" like a single-seat fighter with a certain number of engines. Hostage remarked that if next-generation air dominance capabilities came from pressing "a single button on a keyboard that makes all our adversaries fall to the ground" it would be acceptable. Concepts from the Air Force and industry have so far revolved around supersonic tailless aircraft. One of the key limitations in relying on a single platform is they have a limited weapons load, so the original RFI sought ground-based and non-kinetic solutions, with whatever sixth-generation technology being required to have a larger magazine than current fighter solutions.[43]

There are significant differences between Navy and Air Force visions for their respective next-generation jet concepts, but both agree on some fundamental characteristic aspects they will share. American sixth-generation fighters are to feature artificial intelligence as a decision aid to the pilot, similar in concept to how advanced sensor fusion is used by the F-22 and F-35. They will also have Positioning, Navigation, and Timing (PNT), and communications that allow big data movement between both service's aircraft.[44]

Air Force General Herbert Carlisle said in February 2015 that stealth is "incredibly important" for their next-generation F-X fighter. This contrasts with statements made by Chief of Naval Operations Admiral Jonathan Greenert that their F/A-XX fighter might not be so focused on survivability as to sacrifice speed and payload. Unlike the previous F-22 and F-35 development programs that depended on new technologies that drove up cost and delayed introduction, the Air Force is intending to follow a methodical path of risk reduction to include as much prototyping, technology demonstration, and systems engineering work as possible before creation of an aircraft actually starts. Carlisle describes the sixth-generation strike capability not as just an aircraft, but a system of systems including communications, space capabilities, standoff, and stand-in options.[45]

In March 2015, the Navy revealed they were working with the Air Force to potentially release joint analysis of alternatives (AoA) in 2016 for their next-generation fighters; they are allowed to take a joint AoA, then define a service solution that would be good for each service. The Navy is focusing on replacing the capabilities of the fighter with a wide range of options for the Super Hornet, as well as the EA-18G Growler. The AoA will run parallel to several other design and technology efforts including engine technology, airframe molds, broadband and IR stealth, and new ways to dominate the electromagnetic spectrum. Part of the Navy's calculus will be based on how the F-35C performs as a critical forward sensor node for the carrier air wing. How the fifth-generation F-35C integrates with the rest of the air wing to give greater capabilities than what the platform itself can do may lend itself to the sixth-generation F/A-XX.[46] The Navy aircraft is to have greatly increased speed and range compared to the Super Hornet.[47]

In April 2015, the Center for Strategic and Budgetary Assessments (CSBA) released a report concluding that the next-generation U.S. Air Force fighter should be larger and more resembling a bomber than a small, maneuverable traditional fighter. It analyzed over 1,450 air-to-air engagements since 1965 and found that long-range weapons and sensors have dramatically decreased instances of dogfighting. With the increase of air defense systems using electronic and infrared sensors and high-speed weapons, traditional designs relying on small size, high speed, and maneuverability may be less relevant and easier to intercept. As a result, the CSBA suggests building a fighter significantly larger relying on enhanced sensors, signature control, networked situational awareness, and very-long-range weapons to complete engagements before being detected or tracked. Larger planes would have greater range that would enable them to be stationed further from a combat zone, have greater radar and IR detection capabilities, and carry bigger and longer-range missiles (Long-Range Engagement Weapon). One airframe could be fitted with various attachments to fill several roles. The concept of a small number of large, intercontinental and heavily armed combat aircraft could link itself to the development of the Long Range Strike Bomber.[48]

In November 2016 the USAF Scientific Advisory Board announced studies for a Penetrating Counter Air (PCA) platform that would combine long range, supersonic speed, stealth and maneuverability and be fielded by 2030.[49] PCA would have substantially longer range to fly long distances over the Pacific, especially in a situation where airbases in the vicinity of China are not available[50] or if aerial tankers are destroyed.[51] It would also escort bombers deep into Russia or China, where the anticipated threat includes advanced networked air defense radars. It would include stealth against low or very high frequency radars (like those of the S-400 missile system),[52] which requires an airframe with no vertical stabilizers. Another requirement is significantly larger payload than current air superiority aircraft like the F-22. Adaptive cycle engine technology is an option under consideration for the PCA,[53] given the fact that the alternative would be a very large aircraft.[51]

Examples[edit]

In September 2011, Boeing unveiled a sixth-generation fighter concept for the U.S. Navy and Air Force. It is planned to have supercruise and fly faster and farther than the F-35 Lightning II. Boeing is self-funding the project until an official fighter program starts to have a design ready.[54]

Lockheed Martin's Skunk Works division has revealed a conceptual next-generation fighter design that offers the first hints of an ambitious, long-term technology strategy for the new class of tactical aircraft that will emerge after 2030. The concept was published in a 2012 calendar, which was distributed to journalists. Lockheed Martin has called for greater speed, range, stealth and self-healing structures.[55]

In January 2015, Northrop Grumman revealed it had stood up teams dedicated to developing a sixth-generation fighter and that it would compete for the next fighter. Individual teams were created to focus on the specific separate requirements for the Navy and Air Force. The company indicates it is looking at a supersonic tailless jet, something never created before due to complexity; it may also be optionally manned.[56]

Proposed sixth-generation stealth jet fighters[edit]

See also[edit]

References[edit]

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