VTOL Black Triangle UCAV Concept, page 3

IG,

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A new UCAV concept being developed may very well visually resemble and have similar flight characteristics of the "black triangles" so prevalent in UFO-lore.
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The best UFO UCAV is one which uses a circular plenum to direct air or 'some' kind of thrust out fenestrated side panels in a true disk. The circular plate design helps with structural loads and volume utilization and is furthermore the only way to be the darting agility (at least in the nominally longitudinal axis) often attributed to these craft.

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The VTOL concept is called the "Unmanned Combat Hybrid Armed Vehicle" and will utilize an oil-less Rolls Royce turbofan engine system that propels the craft horizontally and powers hybrid-electric VTOL lift fans as well as powering sensor arrays and directed-energy weapons (ie solid state lasers).
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Snicker. Is it a motor driven by a battery or a battery charged by a motor...

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This particular vehicle concept could match the "best of both worlds" scenario so covetted by the DoD in it's 2006 Quadrennial Defense Review. Those two worlds being rapid strike and endurance over the target area.
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Doesn't take a helluva lot there to improve on what we've got. Frontal area decreases, along with basic (delta=deep roots and long chord) 'shaping for fuel on the front side, lift on the back' will get you a sustained Mach 1.5 drone airframe. It then being a matter of designing a microturbine that can handled the repeated thermal cycles of supercruise (materials and blade shapes) before 'down clutching' to a very low rpm endurance mode on a fixed core. If anything, I imagine this is what the 'oilless' and 'EM or Air Bearing' is in reference too as you treat entire stages like stators and simply pull them from the pressure cycle. True variable cycle costs a LOT of weight and complexity in throat sizing and bypass duct.

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According to aerospace giant Rolls Royce sources the "Unmanned Combat Hybrid Armed Vehicle's" flight speeds could reach upwards of Mach 6 or 7 should the turbofan be augmented by combined-cycle propulsion (ramjet cycling to scramjet for supersonic speeds and beyond). Technology for on-station endurance exceeds 30 hours for a persistent area denial presence or for ISR functions, but that time will eventually increase to 3 to 7 days.
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Crap. How far out are you likely to be from your troops on the ground or ships at sea? If it's more than a 1,000nm I doubt if you are 'in theater' anyway, at which point the ability to apply fires and target tactically is not the force commanders but some suit back in the 5 wall asylum.

If you can fly out 1,500km at 700-800knots, hold for 5-10hrs and come home in another 90 minutes or so on a 10-15 million dollar airframe, you have every platform out there BEAT. Whether they are VTOL, CTOL, prop or jet driven.

No need to pretend this is Aurora in a toy poodle scaled approach. Just match the French Fast/Slow followon to SPERWER.

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Defense industry companies associated with this concept include Rolls-Royce's Libertyworks, Northrop-Grumman, Lockheed and SonicBlue Aerospace.
Very little information seems to be available on this concept beyond Sonic Blue's web site, various defense contractor email exchanges and one or two aerospace publications.
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Yeah, yeah, and the quality of propoganda put out by company X is a function of the empowered brain trust inside the ivory sanctum's walls. Lunchmeat is already behind the eightball on unmanneds and will likely be the laughing stock of the aerspace world when the F-22/35 programs are finally 'done with them'. If they survive at all. Rolls Royce has been caught out attempting to leverage F120 technology in a scaled-for-50,000lb fighter application and so are equally bleeped without a pot to piss in or a program to 'contribute' to. And NorGrumman is about to become a second tier aerospace company known for their avionics, HALE UAVs and possibly building a French Tanker. Sonic Blue is riding the wave in the hopes that nobody notices how out of place the monkey-in-a-suit looks in a room full of other 'corporate types'.

So, let's get real shall we? If the air vehicle weighs 12,000lbs empty, it /hardly/ needs a bloody 5,000lb engine installation rated to 40,0000lbst now does it?

Looking at the size of that endcap nozzle with it's fixed 2D vectoring, I am reminded of the Harrier II forward nozzles. How much thrust does each one of those put out? F402-RR-408 is what, about 26-28Klbst? Divided by four that's 7,000lbst. What engine in the size range dictated by the fuselage nacelle creates that kind of thrust? It's got to be something civil (no weight margin for a burner hit on fuel fraction, no condi nozzle, among other things), probably off a biz jet or maybe a trainer. Which 'rather rules out' the F120/136 technology base unless they're going scaled (which is basically a NEW engine and we all know what that mean$).

If you are pushing 7K out the back, that means that the rest of 'electric fans' have to generate _balancing thrust_ in the amound of at least 7K from the front. Because you're gonna want to have a 2,000lbst margin for weight growth. At least. WHY THEN are all the 'big plenums' in the rear of the wing?

Let's talk about fans within wings in fact. Delta or no, you need SOME structural framing in there and with that as a given, you probably have eaten your entire wing in terms of 'what they're intended for' which is to _haul gas_. The idea of a 'shutter like' cover is also ridiculous because to iris closed means to have an external (in the wing itself) set of doors, top and bottom and this not only violates the integrity of the plenums themselves, it also makes a monkey out of us in terms of the close spacing on multiple such. And then there's the problem with stealth 'coatings' aside, (SWAM weighing so much that it takes two STRONG men to lift a five gallon bucket of the stuff) do you /really/ want a door system which depends on multiple overlapping articulated gaps? And how much penalty do you pay for these when you hit Mach whatever with a piece of metal thin enough to nest atop multiple others on an _outside in_ basis? Okay, so let's assume you REALLY MEAN that these 'fans' change pitch to lie flat and go from blades to doors. That's simple enough. Except it's not. Because if you mount them centrally, they will never rest level with the surface (you can close the hole but not the depression). If you mean that you rotate them from a hingepoint in the plenum wall, them you have problems with the hub connection which is traditionaly the strongest point on a fan. And you STILL cannot fully close off the well because the fans may fold up or fold down but they won't do both without conflicting with each others geometry paths. A simple door in the bottom of the wing that could cover multiple 'fans' without all the articulation reliability problems may be part of the solution, possibly amplifying keel area (directional control) and providing LID options as well. Turn them crosswise into the airstream and you have blown flaps if not TVC.