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These are the only 2 fighter jets I know of with forward-swept wings. (Su-47 and X-29, they're both still experimental). As you can see, they both have their wings in the back, not the middle.

Why is this? To me it seems like those wings in the far rear place the center of lift very aft, meaning a constant nose-down torque.

Is there something precluding a conventional-tailed aircraft with forward-swept wings?

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    $\begingroup$ Becuase it looks absolutely bad ass.... no? That's not the reason? :) $\endgroup$
    – falstro
    Commented Jun 14, 2016 at 7:05
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    $\begingroup$ Also, they're not both "still experimental", they're both cancelled. $\endgroup$
    – falstro
    Commented Jun 14, 2016 at 7:08
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    $\begingroup$ The X-29 was never a fighter jet, nor was it ever meant to be. It was a test platform for NASA. The SU-47 has a similar role, although more geared towards military applications, only 1 SU-47 was ever built, and I'm not sure you can consider it a "fighter" since I don't believe it was ever loaded with weapons. $\endgroup$
    – Ron Beyer
    Commented Jun 14, 2016 at 10:56
  • $\begingroup$ @RonBeyer I think the term "experimental fighter" can still apply. AFAIK, the main reason for exploring the forward-swept wing in both of them was for the agility of a fighter. They are/were prototypes, which don't necessarily need weapons at the early prototype stage. $\endgroup$
    – DrZ214
    Commented Jun 14, 2016 at 11:17
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    $\begingroup$ Technically they are "technology demonstration platforms", the technology demonstrated on both was to be used in other aircraft. Here is a good read on the X-29 program for anybody else who is interested, and has time to read 340 pages $\endgroup$
    – Ron Beyer
    Commented Jun 14, 2016 at 11:29

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These are just two canards with forward-swept wings. There is no general rule that the wing has to be in the back once it is swept forward. In both particular cases the configuration was selected to achieve the highest degree of agility possible. If you command a pitch-up in a conventional configuration, you first need to decrease lift in order to achieve your eventual goal to increase lift. In a canard, however, a pitch-up command achieves a lift increase immediately.

To prove my point that conventional configurations can also be forward-swept, here a few examples:

Junkers 287 in flight

The first big forward swept aircraft, the Junkers 287 research airplane (picture source). The odd engine placement was the result of optimizing the cross section distribution for transsonic flight (what is today called area ruling). The white spots are pieces of sticky tape to attach wool tufts for flow visualization, and the canisters below the wing engines are rockets to shorten the take-off run. The aerodynamically shaped canister on the tripod right ahead of the vertical tail houses a film camera for tuft observation in flight.

Akaflieg Berlin B-11

Here is a real oddity: The Akaflieg Berlin B11 forward-swept tailless glider (picture source). It was never completed because the center of gravity turned out to be too far back. Also, the stall characteristics would have been - how should I say - interesting.

Most two-seater gliders use a slight amount of forward sweep to place the rear pilot at the center of gravity, so the plane can be flown by a single pilot without the need of adding ballast.

HFB-320 in flight

The HFB-320 Hansa Jet was more successful, and here the forward sweep was selected to keep the cabin free of the wing spar (picture: Eric Tammer / source: PlanePictures.Net). However this configuration was not trouble-free, either.

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    $\begingroup$ I think the reason that the wings of the fighter jet are in the back is that this creates the shortest arm between the c.g and the location where lift acts. The reason you see fighter jets with a forward sweep is that they increase the maneuverability at high angles of attack. $\endgroup$
    – Brilsmurfffje
    Commented Jun 14, 2016 at 7:28
  • $\begingroup$ "Tailless" means no horizontal stabilizer? The Akaflieg Berlin B11 seems to have a vertical stabilizer, at least. $\endgroup$
    – David Richerby
    Commented Jun 14, 2016 at 7:57
  • $\begingroup$ @DavidRicherby Yes, that is the idea. It is not a pure flying wing. $\endgroup$
    – Peter Kämpf
    Commented Jun 14, 2016 at 9:52
  • $\begingroup$ @Brilsmurfffje: Yes, the aeroelasticity of a forward swept wing helps in agility. We have that covered in this question. The cg is always close to the wing because it creates most of the lift. $\endgroup$
    – Peter Kämpf
    Commented Jun 14, 2016 at 9:54

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