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In one of the answers to this question about the Concorde's lack of high-lift devices on its wings, it was pointed out that the Concorde, using a tailless delta wing, wouldn't have been able to use flaps, since there was no horizontal tail aft of the wing to counteract the downward pitching moment that would result from deploying flaps.

On the other hand, a tailed-delta configuration (a delta wing with a conventional tail mounted aft of the wing) would have been able to use flaps, as it would have had a separate elevator further aft with the ability to counteract the flap-generated pitching moment. A good example of this would be the design for the Boeing 2707-300, which was to use a tailled-delta configuration and would have had some rather impressive flaps, but was cancelled in 1971 before even the two prototypes had been completed.

Given that it would have allowed the inclusion of flaps, would a tailed-delta configuration have been a better choice for the Concorde than the tailless delta they ultimately went with?

Edit: Better in that it would have greatly increased the Concorde's subsonic efficiency and allowed lower-speed (and thus less potentially-tyre-explodey*) takeoffs.

Quoth the linked question:

...The lack of high-lift devices considerably reduced lift at low speeds, requiring the Concorde to take off and land at higher speeds and angles of attack than if it had been equipped with flaps and slats. As well as greatly increasing drag (and thus fuel consumption) during takeoff and landing, this greatly increased the force carried by the main landing gear and the speed at which its tyres had to spin; as a result, if and when a tyre blew out (due to, for instance, a piece of debris left by the previous airplane to use the runway), the results would be much worse than with a tyre blowout on a subsonic airliner.

...[The addition of high-lift devices], along with slightly larger wings and more powerful engines, would have allowed the Concorde B to dispense with afterburners, considerably increasing its fuel efficiency and range.

* It happened a lot before the fatal accident.

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  • $\begingroup$ You can't tie the fate of one aircraft to a design decision taken thirty-five years before on the basis that you consider that a different decision might have led to a better outcome on that one occasion. Your suggested 'improvement' might have led to poorer outcomes across a range of different parameters. If you're asking if your idea would have been 'better', you need to define 'better'. $\endgroup$ – user30849 May 20 '18 at 9:07
  • $\begingroup$ A canard would be way better. At that moment canard wasn't used probably due the the lack of well tested fly-by-wire system to counter the instability introduced by a front (de)stabilizer. If we were to redo the design today, or did a another more risk-taking design at that time(XB70, Tu-144), then probably that's the way to go. $\endgroup$ – user3528438 May 20 '18 at 15:58
  • $\begingroup$ @user3528438, canard configuration can be just as stable as the tail one and tail one can be just as unstable as canard. After all, F-16, the first fighter designed to be unstable, has conventional tail. The only difference is that for stable configurations tail is more efficient and for unstable ones, canard is (as far as I can tell, both XB-70 and Tu-144 were stable). $\endgroup$ – Jan Hudec May 20 '18 at 22:01
  • $\begingroup$ @user3528438, also remember that Concorde was supercruising at M2, which is way better than any fighter today. At M2, the shock cone is 60° and for efficiency, the aircraft should fit within that. That does not leave much space to put the canards in. $\endgroup$ – Jan Hudec May 20 '18 at 22:10
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Design is compromise

Would a tailplane+flaps have avoided the risk of high-speed tire failures? Quite possibly, but tire failures can still happen and the debris will still hit the underwing where the fuel tanks are.

The solution to that would be a swing wing, which was studied and rejected because of the added weight and complexity.

Ground studies, backed by later flight experience, fully vindicated the earlier decision to avoid any form of variable-geometry wing as a means of achieving the supersonic-subsonic performance compromise. In supersonic military aircraft design, where operational economics is of secondary importance, the "swing wing" is a favoured solution to this problem. In the present state of the art, however, the weight and complexity of the swing-wing hinge mechanism rule it out for commercial operation (Concorde History).

Adding a tailplane

Concorde was meant to be economical (on paper at least). If the sizing remained the same -- the same number of passengers in the slender 2+2 seating -- then the addition of a tailplane would have reduced the main wing area (let's assume that offsets the weight of the added mechanical complexity). But the fuel capacity and thus range would have suffered. Now the Concorde is no longer a transoceanic plane.

If the range was fixed, then the payload would have suffered, considerably raising the fare (in 1980 a Concorde ticket cost £600 -- \$3,900 in today's money) and making the sales team job way harder than it already was (the sonic boom and smoky engines concerns).

Not just the Concorde

Even if the swing wing wasn't rejected, it would not have completely prevented the wing-piercing-rubber -- while searching for tire failures, I came across this:

enter image description here
(avherald.com)

It was survived, just like how the Concorde survived similar incidents prior to the fatal one.

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The beauty of the pure delta configuration was you could get a reasonably low supersonic drag configuration in a planform with a lot of wing area, essential for really high altitude cruise and for reasonable landing speeds without high lift devices. It was a good overall compromise for Concorde's mission.

The Avro Arrow, produced then scrapped in Canada in the late 50s, also used a large pure delta plan form (which is thought to have had some influence on Concorde, a lot of Avro's engineers having joined the Concorde program when Avro Canada vanished). This allowed it to meet the RCAF's specification that required M2+ while being capable of sustaining a 2G turn at 50,000 feet, something no interceptor could do at the time.

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