Monday 8 April 2013

Boeing's latest F/A-XX concept.

Hot off the F-35's latest controversy, Boeing has released its latest artist's rendition of the aircraft destined to replace the F-18E/F Super Hornet, the F/A-XX.

With Super Hornet production coming to an end soon, the U.S. Navy has already started on the process of its replacement. Given that early production Rhinos will have reached their 9,000 hour airframe limit by the 2030s, along with the usual prolonged development schedule of modern fighters, this seems like a prudent move. It also provides an argument against Canada choosing the Super Hornet for delivery in the 2020 timeframe. What good is purchasing an aircraft due to be replaced in a mere 10 years?

So what can we gather from the F/A-XX program so far? Not much, of course, the program is still in its infancy. All we have to go on is a request for information (RfI) from the Pentagon, asking manufacturers for concepts. This RfI doesn't rule out replacing the Super Horner with even more F-35s, but given the Lightning II's many troubles so far, this is far from a sure thing.

One interesting thing to note is the name of the program itself, which is now referred to as the Next Generation Air Dominance (NGAD). This would seem to imply more of a focus placed on air superiority, rather than the JSF's primary strike role. This makes sense given the early termination of the F-22 along with the lack of a true replacement for the F-14 Tomcat. Of course, there is also the arrival of the PAK FA and J-20 into future airspace to consider as well.

Moving on to Boeing's images, one can see how the aircraft is already evolving.

1st F/A-XX concept.  Stealthy.
The first, and earliest, image depicts a rather blunt looking tailless delta design, both with and without a traditional cockpit, suggesting a UAV model. Obviously stealthy, it has its intakes mounted above the wing to improve stealth, likely at the cost of high angle of attack performance. (As the aircraft pitches up, the wings impede airflow into the intakes).

The 2nd F/A-XX concept, more aggressive.


The second image appears slightly more aggressive. With wings similar to the X-47B, along with more traditional intakes similar to the F-22, this concept looks like it would be more likely to achieve supercruise, along with more aggressive manoeuvring.

The newest concept.  
The latest image, released today, suggests an even greater commitment to agility, while maintaining stealth elements. The most obvious difference, the large canards, are most likely there to improve agility, along with adding lift to improve carrier operations. Oddly enough, they appear very similar in layout to those on the Gripen. Canards aren't popular with stealth designs. Large moving surfaces tend to increase radar signature, but the tailess design would help mitigate this. The intakes are quite similar to the F-35's, using a divertless intake deign at the wing root. This likely gives the best compromise between stealthiness and high AoA performance.

All three designs are twin-engine, likely to improve thrust rather than safety. They all incorporate a nacelle design similar to the F-14, YF-23, and PAK FA. Not only does this help flatten the aircraft out, reducing radar signature and improving lift, but the space between the engines allows for easy weapons and fuel storage. The large delta wings should hold quite a bit of fuel as well, especially compared to the small winged F-35.

Likely faster, stealthier, more agile, and longer ranged than the F-35, the F/A-XX could possibly have another advantage; simplicity. With no STOVL version or conflicting requirements, the F/A-XX's development could be a lot more streamlined than the F-35. It's also likely to avoid the costly and over-ambitious technology development of the F-22, A-12, and F-35 and stick with the fundamentals instead of trying to re-write the book.

With Canada needing a CF-18 replacement for 2020, yet a possibly far superior aircraft than any currently available on deck for the 2030s, perhaps Canada should take a "Hi-Lo" approach to its fighter procurement. Buy an affordable, versatile "work horse" fighter like the Gripen now, with plans to procure a higher end fighter like the F/A-XX in the 2035 timeframe. This would avoid another situation like the current CF-18 replacement controversy, where the RCAF is flying old, worn out fighters with limited replacement options.

Is it too early to start "F/A-XX for Canada"?

7 comments:

  1. Well well, "plus ca change, plus c'est la meme chose."

    So the 6th generation super fighter is supposed to have a detla wing and canards as control surfaces. Looks like the eurocanards have actually influenced the design. I thought Canards were so poor in terms of stealth design? The US navy appears to have less confidence in the power of stealth and want to rely more on agility in order to improve the survivability of the fighter.

    In my opinion, the French Rafale most closely resembles this design. The close-coupled canrads increase the aircrafts lift at low speeds by directing air onto the main wings. This is desired in order to facilitate the lift off at low speeds from the carrier. The air intake below the wings also seems inspired by the Rafale.

    The most noticable difference is that the tail fin - vertical stabilizer has been done away with. The tail fin is a major source of drag. Therefore, getting rid of the vertical stabilizer is an old dream of aircraft designer. I assume that thrust vectoring is going to be used in order to increase the stability of the aircraft. That's going to be a major technical challenge. Finally, the jet engine exhaust appears to be directed above the wings. I suspect that this design choice is supposed to reduce the infrared signature from the ground.

    The grand daddy of these tailless designs is the Horten H229. Here's a nice documentary about the aircraft:

    http://www.youtube.com/watch?v=A3UFvYQoiTI

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    1. Bingo. ;)

      Hopefully they take more of a "safe" approach and merely try to refine fighter aircraft as a whole instead of trying to rewrite the book.

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    2. True, but the whole concept of "X generation fighter" is still a fairly new one. Were the F-14 and F-15 marketed as "4th generation fighter"?

      What makes a prototypical "Xth generation" fighter is really hard to pin down, and usually only becomes clear in retrospect, usually by sheer numbers (like the F-86 and F-4), or some rather defining trend (the 4th gen's return to dogfighting capability). The trouble is, the definition is rather muddled sometimes. If stealth is the defining characteristic of a 5th generation fighter, does that mean that the F-117 is 5th generation? If it's "sensor fusion" than that means many supposed 4th generation fighters can be 5th generation through the use of upgrades.

      Who knows what the defining "6th generation" characteristic will be? Will it be the addition of HELLADS-like laser weapons? UAV variants of manned fighters? Or will it be more of a "back-to-basics" approach after all the F-22 and F-35 controversy?

      One thing is for sure though, both the USN and the USAF will be looking for more F-22 like performance. With the F-35 making up most of the fleet, and the F-22 nowhere near its originally planned numbers, not to mention approaching retirement at that time, I think the F/A-XX will lean more towards the "Hi" end of the "Hi-Lo" spectrum. With the F-35 performing so many roles, perhaps the F/A-XX will set out to be more of a leaner and meaner F-22.

      That's my thoughts anyway... Who knows for sure?

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  3. "One thing is for sure though, both the USN and the USAF will be looking for more F-22 like performance."

    based on what?

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    1. Based on the fact that:
      1/ The NATF (naval version of the F-22) never got off the ground, or even the drawing board.
      2/ The F-22's production was severely cut short (185 out of a planned 750)
      3/ The F-35 was predominantly designed with the strike role, not air-superiority, in mind.
      4/ The F-22 will be seriously close to retirement by then.
      5/ The PAK FA and J-20 will likely be flying in numbers by then.

      If the U.S. has decided to abandon its "High-Low" air power model, and strictly fly F-35s, that would come as a HUGE surprise to just about everyone. It's maintained that model since WWII.

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  4. F/A-XX is sorely needed by the US Navy. If SecDef Cheney hadn't cancelled the F-14D,we wouldn't have had to spend the money on the F/A-18E/F, and could've fielded something like this before 2030. As for it being available for export, we'll have to see how the PAK-FA and more importantly, the PAK-DA stealthy strategic bomber program progresses.

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