F/A-XX 6th Generation Aircraft

Last year, the US Navy issued a request for information (RFI) regarding its desire to replace its fleet of F/A-18E/F and EA-18G aircraft in the 2030s. Boeing recently released an updated concept of their 6th generation F/A-XX originally unveiled last year. Lockheed Martin unveiled its own 6th generation concept in a calender distributed to journalists last year. If the development of the first 5th generation aircraft (the F-22 Raptor) is any indication, the 6th generation fighter(s) that enters service after 2030 will look entirely different from either company's initial conceptual proposals. 

Image 2: Lockheed Martin 6th generation concept. 

"The genesis of the Raptor can be traced to a Tactical Air Command (TAC) study known as TAC-85 undertaken in the early 1970s. In 1969-70, TAC-85 began inquiring into what the USAF fighter of the next century would look like. 'Look like' went far beyond the physical appearance of the 21st-century fighter...The initial Request For Information (RFI) for the ATF was issued to industry in June of 1981. Invited to submit bids were nine aerospace companies: Boeing, Fairchild, General Dynamics  Grumman  Lockheed, LTV, McDonnell Douglas, Northrup, and North American Rockwell...The RFI only specified the mission in the vaguest terms. [The] USAF waited for the industry brainstorming to come up with more defined design and capability parameters...The Advanced Tactical Fighter Statement of Operational Need (ATFSON) in November 1984 detailed the projected deficiencies of current generation fighters. This statement resulted in Congressional funding and approval for the ATF in 1985. The REP [Request Final Proposal] for the ATF was issued in July 1986." - Lou Drendel, 2011

The following timeline shows key dates in the Raptor's design and manufacturing evolution. Dates within parenthesis give a rough approximation of what can be expected of  the 6th generation development program. By no means are the estimated dates conclusive or set in stone. It is definitively known that the  RFI was issued by the US Navy in 2012. It is also definitively known that the US Navy plans to field the 6th generation Super Hornet replacement sometime after 2030. Given the immediate issue of F-35 procurement, it is likely that the 6th generation replacement program will be delayed beyond 2030. Current plans project the F-35 production line will remain open until at least 2036.

Timeline of Raptor Evolution

1981 (2012) RFI issued
1985 (2016) Funding Awarded by Congress
1986 (2017) Competing Firms Finalized
1990 Evaluation Concluded (2021)
1991 Raptor Declared Winner (2022)
1994 Engineering, Manufacturing and Development (EMD) contract (2025)
1997 F-22 First Flight (2028)
2001 Lot 1 Ordered (2032)
2003 First Deliveries (2034)
2005 IOC Reached (2036)

In 1981, none of the initial RFI proposals shown in the image below resemble either the YF-22 or the YF-23 (image courtesy of YF-23.net). Given that the USN issued the RFI in 2012, the 6th generation program is likely in the equivalent stage of development. Meaning that is is unlikely the conceptual images released by Lockheed Martin or Boeing will look like the final product or even the prototype.

Program requirements changed over time which partially contributed to the disparity in designs (e.g. stealth became a dominant factor). Lockheed Martin and its developmental partners (Boeing and General Dynamics) went through dozens of design iterations before submitting the Lockheed Model 090P shown below for the final proposal. The USAF chose Northrop Grumman and Lockheed Martin as the finalists in the concept demonstration phase. (image courtesy of Lockheed Martin)

Due to airframe weight concerns, Lockheed decided to completely redesign its initial Model 090P proposal during 1987. The redesign process yielded an aircraft that resembles YF-22. (image courtesy of Lockheed Martin)