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Variable Geometry Pitch Control

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


       [+]... 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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