I just don't see how this thing is going to get the range advertised with the size advertised. Isn't there a reason airplanes have wings? I forgot what it was. But I'm fairly certain they aren't cosmetic.
Cutting it down to a not-strictly-accurate-but-it'll-do explanation: Without wings (or other "lifting body" effect), you need to
directly fuel the lift, as well as the horizontal thrust. This could be by a single (or coordinated multiple) thrust giving diagonal thrust for "horizontal travel while staying airborne"[1][4] or by two separate systems[2][3], one of which mainly gives forward thrust the other a downward.
With wings, you fuel the forward thrust and the wings generate the lift as a result. Yes, this
is at the expense of some drag (thus slightly more thrust is needed than a plane supported by some sort of a separate lifting system that adds no weight and needs no wings to be dragged through the atmosphere). And in several ways this is why airliners travel high up through thinner air, albeit that this also needs more wing to generate lift.
See also the
Ekranoplan for systems that effectively double the lift (thus decreasing the need for lift-inducing drag) at the expense of having to maintain extremely low altitude (to the extent that they're treated much the same as hovercraft, and as such are amphibious ships (being almost exclusively water-landing, but capable of travel over land assuming no obstacles), not fully triphibious (although some variants have the wherewithal to attain higher altitudes at the cost of extra power and/or a limited duration).
But there are probably people here more familiar with all matters avionic who would wish to be more precise about my simplifications of the matter...
[1] This is how the Skycar does it, at low velocity, IIRC. VTOL capability from direct upwards thrust, rotating forward to gain forward momentum... although (like the Osprey rotating-wing aircraft) I'm pretty sure it also has wing-like (and lifting-body) stylings to its airframe so that at nominal full speed it has wing-effect as well. But the single (or usually linked-dual) thrusters of a personal jet-pack is just leaned forward to get 'forwardness', and you generally (apart from what little you get from the pilot's body) can't get enough non-thrust lift to lean straight forward. Compare with the "birdman" jet-assisted wing-thing, in which it's all forward thrust, but (to my knowledge) he's never managed to take off from the ground... Even in a base-jumping situation, because he needs the velocity attained from lengthy free-fall to allow his small wing to gain enough lift-effect. I don't even know if his jet-engine has much more power than that needed to "sustain" is forward velocity, but I suspect it couldn't get him from zero to flight-speed in any decent time, without the free-fall assist.
[2] Early (and some later) VTOL designs of plane had a number of engines dedicated to the vertical component, but which were effectively dead-weight when the more classic thrust-engine(s) kicked in enough for normal flight.
[3] On the other hand, there are ones that are technically two systems but the power comes from one. While it looks like (reading up on current literature) that the current F35-B Joint Strike Fighter variant that was originally intended to be fully VTOL has been abandoned in favour of STOVL, the interesting nature of this system is that the heavily-vectorable rear jet (that could be made to point straight down) can also be mechanically linked to a more modest-weighing fan within the midst of the airframe with shutters above and below opening to allow passage of air when needed, but being closed so as not to disrupting standard/supersonic flight at all. For a semi-practical demonstration, it was featured in Die Hard 4.0, but as that's a film it may or may not be close to the reality.
[4] As is also done with the Harrier, in its non-conventional modes. I have a soft spot for the Harrier, having seen one being test-flown, back before it was made generally known to the public... it was just visible rising and falling behind a line of trees around a particular test-site that I had happened to be passing. The Harrier solved the problem of multiple engine units, dead-weight and the like by sending the engine power down (or back) through four vectored-thrust nozzles, giving it VTOL (with no significant payload), STOVL (with heavier payload, especially with ramp-assistance) and a pretty decent (although, unfortunately in the 'modern world' of air combat, not supersonically capable) standard flight mode with the additional benefit of some partially-reversing thrust that (if the pilot can moderate it, and control the aircraft sufficiently) give a distinct manoeuvring advantage against faster attacking aircraft, as some people say was the case in the Falklands conflict.
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Topic: We Finally Reached the Future (Read 3229 times)