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Variable Geometry Pitch Control

Swinging the wings changes the center of pressure.
 (+1, -2) [vote for, against]

Build a small, fast tail-less airplane with a quick and powerful variable-wing-geometry mechanism. When you want the nose to go up, sweep the wings forward a bit. When you want the nose to go down, sweep the wings back a little.

When you want to go faster, adjust the center of gravity by pumping fuel or something, then sweep the wings back. Good luck.

 — baconbrain, Oct 13 2008

Helicopter with no tail rotor http://www.gather.c...eId=281474977472381
Likewise dispenses with a control structure for increased efficiency. [spidermother, Oct 14 2008]

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[+]... you could hire a midget robot to climb over the plane changing the CG.
 — FlyingToaster, Oct 13 2008

 // adjust the center of gravity by pumping fuel or something //

....or maybe praying..... check out you have a good religion before takeoff......
 — 8th of 7, Oct 13 2008

What is the advantage? No tail? What is the advantage over a delta wing?
 — Texticle, Oct 13 2008

 The advantages are no tail, and no separate pitch-control surfaces/inputs. Probably a better speed range than a delta wing.

 It uses the VG mechanism for an additional function, at the cost of having to mess with the CG to be able use the wing-sweep for speed flight. It's probably pointless, but it's possible, I think.

You could build a compact airplane this way, with no tail and folding wings, maybe.
 — baconbrain, Oct 13 2008

I assume this is dynamically stabilised like a Segway. It's possible to build a static, stable, tailless aeroplane by using long, highly swept wings, but part of the wing in such designs provides downforce, which I assume you want to avoid. This could have a better lift to drag ratio than conventional designs, since the problems of the relatively non-lifting tailplane (or canard) are avoided.
 — spidermother, Oct 14 2008

Northrop and Mitchell have built aircraft without tails, but they still have control surfaces (very busy ailerons).
 — FlyingToaster, Oct 14 2008

 The 'flying wing' or "tailless' design has one persistant shortcoming - yaw control. One answer is to put a substantial dihedral into the design to give some measure of lateral control. But without a stabilising fin, landing in even a slight crosswind is a nightmare, since if the only way to turn is to drop a wing - when you're doing your best to keep the wings level - it can be a tad stressful. It's possible to yaw by advancing and retarding the throttles, but again, on landing, it's a bit awkward - and on a jet, there's an appreciable lag between throttle movement and thrust response, if an increase in power is called for.

The Vulcan bomber is a nice delta design - almost a flying wing - but of course with a fin at the back.
 — 8th of 7, Oct 14 2008

Yaws, indeed. I was thinking about putting a swiveling fin in front, atop the fuselage (what there is of a fuselage) under very rapid computer control.
 — baconbrain, Oct 14 2008

 The B2 "gets away with it" because of size and inertia and (being a military aircraft) its rather luxurious power-to-weight ratio. [baconbrain] specifies "small" .... big aircraft have a measure of stability simply by the larger moments required to change attitude.

They tried to lose the tail fins on the F-117, but they couldn't -too small, too easy to flip over.
 — 8th of 7, Oct 14 2008

A wing, variable or static, is considered a control surface isn't it?
 — quantum_flux, Oct 15 2008

No. To qualify as a "control surface" it has to move relative to the airframe, under command.
 — 8th of 7, Oct 15 2008

//The Vulcan bomber is a nice delta design// - understatement & amen
 — lurch, Oct 15 2008

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