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18

Tailless means no horizontal tail, but a vertical tail is still allowed. Examples are the Convair F-102 or Convair B-58. Convair B-58 Hustler (picture source) Compare this to a flying wing: Here even the vertical tail is left off. Since a classic delta would have too little lever arm for yaw control, this requires a higher aspect ratio wing. An example is ...

17

It was obvious to the design team that conventional aircraft could not satisfy the required specification; knowing little about high-speed flight and unable to glean much from the Royal Aircraft Establishment or the US, the team at Avro investigated German Second World War swept wing research. The team estimated that an otherwise conventional aircraft, ...

13

Because it was something of a Burt Rutan trademark since his early days. His first designs, the VariViggen and VariEze, had such a wing already, and apparently he saw no reason to optimize the wing of the Starship. Rutan VariEze in flight (picture source) The only true innovation was a variable geometry canard, which he even patented. Being only 85% scale, ...

11

The wing design is different between F-16 and F-22 (which is similar to YF-23) because the requirements were different. The wing of F-22 (and that of F-23) were designed with stealth in mind, with the wing (and control surface) edges parallel to each other. There was no such design requirement in case of F16. F-16 is a highly maneuverable aircraft in its ...

10

Benefits of a delta wing: Due to the large root chord, a delta wing combines low relative wing thickness with a sufficiently thick wing spar for a lightweight structure. Since a low relative thickness keeps wave drag down (a drag component which occurs only in supersonic flow), this makes delta wings especially attractive for supersonic aircraft. The large ...

8

Aspect ratio. Look at your two images: both wings offer the same wingspan, but the former requires a lot more wing area for it. Wing area is weight. More wingspan for less wing area means better fuel efficiency and thus better range. Poor aspect ratio, leading to excess induced drag, is a major disadvantage of delta wings. Much of modern stealth design is ...

8

I would not say that no other bomber ever had delta wings. Convair B-58 Hustler and Mirage IV both have delta wings. They are both supersonic though. The B-52 did not have to worry too much about MTOW and empty weight since SAC already had bases with long runways capable of really heavy aircraft. That's thanks to B-52's predecessor B-36. The B-36 was the ...

7

The effect of a horizontal tail can be built into a tailless aeroplane in two ways: By integrating into the wing profile: a horizontal s-shape with the trailing edge turned up. By combining positive sweep with negative twist.

6

The F-15 wingtip is a "raked" tip configuration, which increases lift and decreases drag.1 []2 This is the design decided by the USAF after discovery of several design deficiencies during initial flight test which included aeroelastic deficiencies (wing bending) and aerodynamic effects (buffeting). "In early June 1974, the Air Force flew the “raked” tip ...

6

No, not at all - there are at least two Delta Wing aircraft that feature a conventional tail, and they are the Gloster Javelin and the Mig 21 https://en.wikipedia.org/wiki/Gloster_Javelin https://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-21 (Courtesy of http://airheadsfly.com/) In addition (and I believe this is within the spirit of what you've asked) ...

6

1. Aeroelasticity Unlike a tailplane, a delta wing is more rigid due to its much bigger chord and multiple spars, so control reversal due to aeroelasticity isn't a special concern. Big subsonic jetliners typically lock the outer ailerons at high speeds. Concorde featured a similar function for the outer elevon, but only if $V_{MO}$ is exceeded by 25 knots ...

5

Your question is about friction drag while the text is mainly about aspect ratio. You seem to explain the choice of aspect ratio to be based on friction drag. This is not correct. Here and here are some good answers to explain the choice of aspect ratio. You will see that it has mostly to do with structural strength and wing volume to pack enough fuel. For ...

5

The Gripen and Eurofighter are canards with a delta wing (as is the J-37 Viggen). This, coupled with relaxed stability, gives the first two unmatched maneuverability, and good transsonic and short-field performance. While the Viggen is a stable design, it too has very good short-field performance. The Mirage III (and the F-102, F-106, B-58, J-35 Draken and ...

5

No, a higher sweep angle will reduce lift even more. All aerodynamic forces scale with the dynamic pressure, the product of air density and the square of airspeed, divided by half. If a wing doesn't produce lift, move to denser air or speed up. However, drag will also scale with dynamic pressure, and there is more which influences lift. One is the angle of ...

5

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 ...

4

Concorde did not have any flaps or slats as mentioned here. This is due the fact that they don't have any tails, and wing trailing edge devices do the elevator and aileron jobs and they are called elevons.

4

First, thank you for unearthing this unorthodox design! However, it shows that paper airplanes don't scale well. Nevertheless, it follows the same laws of physics, so the same equations should apply for a quick performance evaluation. What have we got? A flat plate airfoil. Maximum lift coefficient will be between 0.7 and 0.8, so minimum speed at a given ...

3

I know this was answered a while back but let me give you my two cents. As explained by Peter a combination of the wing swept and low aspect ratio affect the lift production of the wing. But another effect also takes place; vortex lift. aeroalias explains it very nicely on this post: What is vortex lift? In short vortex lift is lift generated by the ...

3

No, for several reasons What you want is to compensate for the additional lift from downward deflected flaps at the back of a flying wing with vectored thrust. As @Sean points out this will not bring a noticeable net benefit if the lengthwise location of both forces is similar. But that is not all. Besides the force equilibrium around the flying wing you ...

3

A slender delta wing is a delta with low aspect ratio. The use I have seen is in the study of vortex lift, which is present at high angles of attack. What is vortex lift?

2

'Rest of the world' hasn't gone towards delta- only the previous generation European combat aircraft have (along with India). Also, none of the fifth generation aircraft have anything resembling delta wing. In fact, there are few 'pure' delta wings aircraft anymore- most of them are modified delta or have canards. Delta wings have a few disadvantages- the ...

2

Because, although we often conceptualize Lift as all acting through the "center of Pressure" of the wing surface, this is a fiction, done only to aid in visualizing the total lift, and it's effects, and to aid in doing simple calculations that rely on this approximation. In actuality, Lift itself is an artificial abstraction, as it is just a portion of the ...

2

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, ...

2

No. Thrust vectoring produces a nose-up pitching moment by pointing the engine nozzle upwards, which pushes the aircraft's tail down and its nose up. Extended flaps increase total lift, and produce a nose-down pitching moment, by deflecting air downwards at the trailing edges of the wings, pushing the aircraft's tail up and its nose down. As the engine ...

1

Yes, but it may not be worth it. In principle it is absolutely possible to use thrust for attitude control of a vehicle. To cite a few examples, the F-35, X-15, and Harrier all used ducted jet exhaust or high-pressure bleed air for attitude control during low dynamic pressure phases of flight. You correctly point out in the question that the thrust would ...

1

One very strong reason thrust vectoring is of little or no use to offset flap-induced pitch moment: you reduce thrust to idle or near idle during landing, which would make the thrust vectoring ineffective. The Harrier lands at higher throttle (it takes much more than 50% power just to hover with no stores aboard). If you were using fans at the nose, driven ...

1

I'm not sure why we're assuming that flap deployment will cause pitch instability. As far as I'm aware, flap deployment moves the CoP rearward, which should make the aircraft more stable. I may be missing something here, though, I'm still working my way through Perkins&Hage. I'm not quite following Peter's argument about gusts. For now we'll work under ...

1

One major issue with a delta wing was discovered in the early days of supersonic fighters: delta wings don't handle well at low speeds. At high angle of attack, they (like any highly swept planform) exhibit strong "Dutch roll" in which roll and yaw are coupled in an oscillation, and because they stall at very high angles of attack the Dutch roll comes on ...

1

Slender wing having a very high sweep angle which typically Λ>65°. The non-slender wing is having low to moderately swept (35°–55°) wing planforms.

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