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VTOL the hard way.

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Conventional fixed-wing aircraft use a propeller or jet engine to move forward, creating a breeze over the wing which, in turn, creates lift. Under favourable circumstances, this lift is sufficient to get the plane off the ground.

VTOL aircraft come in two main types. The first is the helicopter, which swings two or more long, thin wings around in a circle. This creates the necessary breeze and, hence, the lift. Helicopters, though, are manifestly unsafe.

The second type of VTOL aircraft uses nozzles to direct the thrust of a jet engine downward, pushing the plane up. This works, but is horrendously noisy and expensive.

Fortunately, MaxCo. has devised a third option which combines the disadvantages of the first with the drawbacks of the second.

Our prototype looks somewhat like a normal aeroplane, but with two differences. First, the wings are more or less symmetric front-to-back, with the bulge in the middle of rather than toward the leading edge. Second, the jet engines (of which there are two on each wing) are mounted unconventionally. The inboard engines are mounted on pylons well ahead of, and just above, the wing. The outboard engines are mounted well behind, and again just above the wing. The outboard engines also back-to-front, which worries a lot of people.

When all four engines are powered up, the result is a phenomenal breeze across the upper surface of the wing. This breeze runs backward across the inner part of each wing, and forward across the outer part. The forward and backward thrusts cancel eachother out, so the plane does not move forward or backward. It does, however, rise vertically due to the air passing over the wing surface.

Once at a suitable altitude, the back-to-front outboard engines are throttled back, and the plane moves forward in the usual way. Of course, throttling back the inboard engines will cause the plane to move backward, but some people like that sort of thing.

MaxwellBuchanan, Aug 12 2017

Coandă effect https://en.wikipedi.../Coand%C4%83_effect
Well-known [8th of 7, Aug 12 2017]


       I had thought about something similar awhile back. Never posted it though.
RayfordSteele, Aug 12 2017

       All a wing does is deflect the oncoming air downwards. I don't see the advantage of this idea over simply pointing the engine exhaust downwards a bit, i.e. vectored thrust.
EnochLives, Aug 12 2017

8th of 7, Aug 12 2017

       //I don't see the advantage// Did I say there was an advantage?
MaxwellBuchanan, Aug 13 2017

       This is not how a wing works. An airofoil, when forwardness is caused to it, introduces a difference in air pressure between the top bit and the bottom bit – the bulgingness makes it happen. The air takes a lot longer to get across the top bit than it does the bottom. Consequently, the air that has passed across the top arrives at a later time, at the same time as the air from the bottom. This difference in pressure causes lift (or elevator if you're foreign).   

       One way of improving this idea, hencethen, is to have all the engines pointing inward at the fuselage. This would provide a dramatic safety improvement in the case of four simultaneous catastrophic engine failures (a euphemism for when an aero engine emits engine fragments at an insanely high speed, in the direction of the cabin and passengers).
Ian Tindale, Aug 13 2017

       // have all the engines pointing inward at the fuselage. //   

       <frowns, and points again at the link to Coandâ Effect>   

       // for when an aero engine emits engine fragments at an insanely high speed, in the direction of the cabin and passengers //   

       In an axial-flow turbojet, a catastrophic failure typically results in high-velocity debris being ejected at right angles to the engine. Relatively little debris is ejected rearwards, and rarely at high velocity.
8th of 7, Aug 13 2017

       //This is not how a wing works.// If you can blow enough air over the surface of a wing, it will generate lift.
MaxwellBuchanan, Aug 13 2017

       <smiles, nods, points yet again at the link to Coandâ Effect>
8th of 7, Aug 13 2017

       ([normzone] searches through his own ideas, looking for something appropriate for gratuitous linking .... Nope, I got nothing.)
normzone, Aug 13 2017

       The really hard way to do VTOL is to use hot air balloon technology, whatever that is, but souper it up to the max. Megamontgolfierisation. Faster, more powerful, more impressive, and more of it. But smaller.
Ian Tindale, Aug 14 2017


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