First Hover Flight Test of X-50A Dragonfly 301
kbielefe writes "On Wednesday, flight testing began on the X-50A dragonfly canard rotor wing unmanned aircraft. For those of you not familiar with the dragonfly, its rotors work like a helicopter for takeoff, hovering, and slow-speed manouvering, and then lock into place like a fixed-wing aircraft for cruising. The X-50A's reaction drive makes it "much lighter, simpler and more affordable to operate and support than traditional rotorcraft." And the technology is scalable to larger, manned vehicles. Truly a revolutionary aircraft, with a multitude of potential military and commercial applications." There are some more photos and artwork.
That was fast (Score:5, Funny)
That sure was fast...
Deathtrap? (Score:3, Insightful)
So far, our attempts at bridging the gaps between helicopters and fixed wing aircraft have met with disaster. Take the Osprey, for example. I don't know who it was but he said that it took the worst features of both types of aircraft and mashed them together with poor engineering. Hopefully this new aircraft does not suffer the fate of the Osprey... and her pilots.
Re:Deathtrap? (Score:5, Informative)
Did you know that in the 50's the Army almost decided not to use helicopters at all after about a hundred soldiers were killed during trials of the Piasecki helicopters? There were people in the Army who were screaming that it was criminal to keep putting men into helicopters.
While I think that the Osprey getting grounded for a year and a half while they fixed the safety-critical problems was appropriate and justified, I'm glad that it's back in the air, and I think that it can really change the face of airmobile combat.
Re:Deathtrap? (Score:2)
It doesn't seem to have gotten much better. There is a reason the A-10 is in the US inventory; helicopters are flaky. Their slow at low altitude, big and soft. Rifle bullets will break things and make a mission very unpleasant.
they're "flaky"!? (Score:4, Informative)
most people don't realize that helicopters share EVERY flight characteristic (sans high speed) with a fixed wing aircraft, including the ability to "glide" (they call it autorotation in choppers, the air rushing up through the rotor keeps it spinning, and you flair at the last moment. every helo pilot can do it, and you land without a scratch as long as the surface is apporpriate)
Re:Deathtrap? (Score:4, Insightful)
I'm pretty sure the number is awfully close to zero.
There are NO armored airborne personnel carrying vehicles. Zero. That means, if you're flying in a C-130 or a Sea Stallion, that there is pretty well nothing between you and fiery death at the hands of bad guys.
It's a problem that is solved by tactics. The Osprey permits a larger variety of tactics (because it's faster and longer-ranged than other heavy lift helicopters).
Being in the Army is dangerous. That's what soldiers sign up for. It's up to the engineers (that's me) to provide them with the best possible hardware to complete their missions, but there is no such thing as a "safe" combat insertion vehicle.
Re:Deathtrap? (Score:5, Interesting)
Re:Deathtrap? (Score:2)
Re:Deathtrap? (Score:2)
How do you do SAR with a fixed-wing aircraft? Search, sure. But the rescue part is tricky.
And don't even try to pretend that Fulton STARS would have worked in Vietnam.
Re:Deathtrap? (Score:2)
The Osprey has had some problems. Most aircraft go through "problem" stages. The history of fixed wing aircraft has far more deaths on it's account than the Osprey.
Joint Strike Fighter (Score:2, Insightful)
Sure, it may make some sense to get the Navy and the Air Force to jointly develop a plane, although some compromises would have to be made and problems are sure to develop.
But to add as a requirement VTOL for the Marines? Oh my God! This is just so stupid! And the way that they're doing it only makes matters worse! Lockheed-Martin won the contract with what can only be described as a truly regretable approach to vertical takeoff that involves generating e
Re:Joint Strike Fighter (Score:2, Insightful)
Hmmmm, seems to me that is the point of calling it air superiority!
I agree on the JSF tho, it is a swiss-army plane, like a swiss-army knife, and it will be expected to do multiple jobs, by replacing dedicated platforms that were designed specifically for certain combat roles. Despite it's versatility, I really doubt it will be as good at any single job as the planes it is replacing were.
Re:Joint Strike Fighter (Score:3, Insightful)
Re:Joint Strike Fighter (Score:2)
Or so I remember reading.
Re:Joint Strike Fighter (Score:2)
P.S. The main feature of the A-10 is its GAU-8A Avenger cannon, which is much more powerful than an M61 Vulcan (50% larger caliber, much higher muzzle velocity, DU warheads, discarding sabot ro
Re:Joint Strike Fighter (Score:2)
Re:Joint Strike Fighter (Score:3, Informative)
I have no idea what you think is so bad about the lift fan design, what "enourmous mechanical stresses" are you talking about which aren't present in a traditional STOVL aircraft? Harriers and the Boeing JSF entry both c
Re:Joint Strike Fighter (Score:2)
Then think about that gear shaft assembly they've crafted to make this thing work. What was it again, something like 50,000RPM? Translating torgue generated from the engines along the Z-axis into lift along the Y-axis? The pla
Re:Joint Strike Fighter (Score:2)
Different problems require different solutions.
Re:Joint Strike Fighter (Score:2)
Shshhhhh...don't tell anyone about this problem. Otherwise, millions of turbine helicopters will start falling out of the air. Sheshhhhh.
Something tells me they have enough experience at understanding the strains and stresses of transmissions in helicopters that they fundimentally have th
Re:Joint Strike Fighter (Score:2)
The "ragged edge of stability" isn't so ragged when you have a full-authority digital flight control system. The inverted pendulum problem is trivial anymore. I can think of half a dozen combat aircraft that wouldn't know to keep the pointy end into the wind without digital flight controls, and many more whose performance and survivability are dramatically improved by same.
The clutch on the lift fan is a huge failure point. The Boeing design was far superior. S
Re:Joint Strike Fighter (Score:2)
Great! Now bring the rotor to a full stop and lock it in flight position, while giving the plane enough vertical speed so that the then fixed wing will carry it, and don't forgett not to drop down those 20 feet in the meantime.
If you made it that far, sooner or later you will want to land. Slow the plane enough the wing won't get dammaged when unlocking it, make the wing rotate fast enough so you get enough lift to control descend - all th
Re:Joint Strike Fighter (Score:2)
Re:Joint Strike Fighter (Score:2)
It makes a LOT of sense to get many forces to agree on the same basic plane design, and includes 8 member nations in addition to our own forces.
The STOVL version isn't only for the Marines. The UK wants it as well.
Lockheed's design was better in a great many ways. If you've seen the report on the contest and the decision-making process, you'd change your tune (if you didn't hate America so much).
Re:Joint Strike Fighter (Score:2)
Besides, what role do the Marines have for a fighter aircraft? If they want VTOL, they've got their helicopters. Why the desire to deploy from smaller boats when we've got the concession on big boats?
The plane is designed by Congress.
Re:Joint Strike Fighter (Score:2)
Re:Joint Strike Fighter (Score:2)
Besides, as you have just said yourself, only 300 or so will be bought by the Marines. So why compromise the thousands that will be built by USAF/USN?
I don't know the first thing about building airplanes. But I understand design principles. The process by which the design for this plane was p
Re:Joint Strike Fighter (Score:2)
The JSF is a good program (granted there are many that are not). I have some friends and a particularly close relative working inside the project, and your "concerns" are way out there.
First, the current generation of planes must be replaced.
Second, the grandparent is right: There is no compromise between the conventional and carrier versions and the STOVL.
Third, the lift fan is a new technology. It demonstrably gives the STOVL version much bette
Re:Joint Strike Fighter (Score:2)
I know a lot about building airplanes, and a lot about design principles. I'm telling you that there's no reason that you can't have a good design that is capable (in one variant) of conventional takeoff, and another variant that does STOVL. (Boeing did a great job. Lockheed, not so much.) Aircraft design is far more malleable than you seem to believe.
"Leave engineering to the engineers." Part of engineering is to come up with soluti
Re:Deathtrap? (Score:2)
Re:Deathtrap? (Score:2)
Re:Deathtrap? (Score:4, Interesting)
There are (thousands?) of Harriers in service, and surprizingly few incidents compared to the number in use (and how they are used - eg in an actual conflict).
They built 10 Osprey V-22 aircraft for testing. In April of 2000, one V-22 crashed during a test flight and killed 19 marines. That alone is nearly two people dead for every craft ever built. (Note: Check date, might be wrong!)
Which do you suppose is the safer technology?
=Smidge=
Re:Deathtrap? (Score:5, Informative)
http://www.latimes.com/news/specials/harrier/la
"Over the last three decades, it has amassed the highest rate of major accidents of any Air Force, Navy, Army or Marine plane now in service. Forty-five Marines have died in 143 noncombat accidents since the corps bought the so-called jump jet from the British in 1971. More than a third of the fleet has been lost to accidents."
"If the Harrier had been decisive many times in battle, we would all still regret horribly the tragedies of the pilots who have been killed, but at least you'd be able to say that the Harrier made a difference," said Philip E. Coyle, the Pentagon's chief weapons tester from 1994 to 2001.
"What makes this situation so difficult is that we just don't have that kind of battlefield record to support the accidental deaths."
In the Persian Gulf War in 1991, the hot thrust-producing nozzles in the heart of the fuselage -- the devices that allow the Harrier to rise and balance in the air -- made the plane a magnet for heat-seeking missiles. Its loss rate was more than double that of the war's other leading U.S. combat jets. Five Harriers were shot down and two pilots died.
"It's the most vulnerable plane that's in service now," said Franklin C. "Chuck" Spinney, who evaluates tactical aircraft for the Pentagon. "You can't hit that thing without hitting something important."
http://www.nationaldefensemagazine.org/article.
"The AV-8B Harrier--a single-engine attack jet that can take off vertically and hover--has a mishap rate of 12 per 100,000 flight hours, among the highest in the U.S. military aviation community. But only one-third of Harrier mishaps are caused by human error, Dirren said. "Two-thirds [of the mishaps] are related to the aircraft failures."
http://www.globalsecurity.org/military/systems/
"In 1982, after eleven years of AV-8A operational flying, including 55 peacetime aircraft losses, the Commandant of the time (Gen Robert Barrow) asked the Harrier community to address the serious problem of flight safety. The impetus for his concern was "a high mishap rate within the AV-8A community... anticipated continuing turbulence... and a pressing requirement to reduce the mishap rate in order to provide the assets needed for successful transition to the AV-8B." At the time, the community had a cumulative Class A rate of 39 per 100,000 flight hours."
"By 1998, USMC Harrier operations (including Naval Air Systems Command) had resulted in 17 fatalities, one permanent disability and 68 AV-8B aircraft lost. With a cumulative Class A mishap rate of 12.1 per 100,000 flight hours, the AV-8B has consistently outpaced all USMC aircraft types in this statistic."
The FAS website estimates 815 Harriers built in all models all the way from the Kestrel and P.1127 test planes
http://www.faqs.org/docs/air/avav83.html
Re:Deathtrap? (Score:2)
Just curious, anyone knows how this compares to a regular automobile ? If it is a wartime machine, combination between helicopter and airplane, and it is a lot safer than riding your average car, then it seems quite fair to me.
Re:Deathtrap? (Score:3, Informative)
Just curious, anyone knows how this compares to a regular automobile ?
If your car has a problem with the steering, you put on the brakes, and maybe have enough steering capability to get out of traffic. If something jiggles loose in the engine, even in the worst case if a piston were to stick, a rod thrown or timing belt cracked, timing got out of wack and you busted the valves and cracked the block, etc, you stick it in neutral and coast to the side of the road.
The Harrier has had "steering" and engi
Re:Deathtrap? (Score:3, Informative)
But ask any British Falklands vet what he thinks of the Harrier and I bet you he'll love 'em. So they have their uses.
Re:Deathtrap? (Score:2)
Re:Deathtrap? (Score:2)
I think the other reply was much mre interesting. (About the total number of accidental failures & other problems). Although I'm sure most people wouldn't consider anything designed to fly through a war zone to be "safe" by most standards. Had the Osprey seen real service, something tells me it would be even more fragile and the accident rate would be
Re:Deathtrap? (Score:3, Interesting)
Although I'm sure most people wouldn't consider anything designed to fly through a war zone to be "safe" by most standards.
I would feel much safer in an F-15 or B-1B than I would in a Harrier or Osprey. But these planes generally fly higher than 50 feet. Perhaps a better way of saying it would be that you don't consider any aircraft designed for close combat support (think helicopter hovering at low altitude) safe.
Re:Deathtrap? (Score:5, Insightful)
Yeah, actually I do think you should at least have heard of this.
The Osprey is supposed to be a replacement for the very aged Chinook helicopters.
If ever the military had a vehicle that outlived its usefulness it was the Chinook.
My father was in 'Nam and he tells me that he couldn't get out of those things fast enough. They were flying bullseyes as far as he was concerned.
The Osprey has the range and speed of a propeller aircraft but the VTOL capability, and the hover ability of a helicpoter.
This is acomplished by putting extremely large propeller (turboprop) engines on the end of the wings. The largest damn propellers you are ever going to see. The ends of the wings actually rotate 90 degrees to facilitate take off and landings.
When they first started testing this thing they found a lot of flaws. Some where engineering problems, but there is one nasty one they have been working on.
The engines can create an unusual vortex that has never really been seen before. When this vortex happens they loose lift and control of the aircraft and it crashes.
Is it a bad aircraft that we need to give up on?
I don't really know.
John Glenn seems to think the Shuttle's are flying death traps and we were better off putting capsules on top of rockets.
The Hubble was a real mess when it was first put in orbit as well. There was an enormous public outcry after the press labeled it 'a failure'.
Hmmmm some failure.
The B-1 bomber also suffered a number of crashes in testing.
Aviation is HARD and DANGEROUS. Someone else already said it for me, it is about time we took the 'pilot' out of test pilot. I can only imagine what the difference in public perception would be if the Osprey had gone through an unmanned testing phase.
The Osprey does hold tremendous promise though. If we can iron out the problems in it, it really would be a new category of aircraft. Something that can economicaly provide city to city air service, something that can bridge the gap between helicopter and airplane.
While I am not yet convinced that they can get a grip on the vortex problem, I am very far away from saying they need to give up.
Airborne! (Score:2)
But I have to tell you, jumping from a Chinook (one of the fastest choppers, by the way) was like jumping into a pile of matresses compared to the shock of exiting a C-141. Not that anyone ever asked the users of the equipment what we thought. We're just soft cargo.
-cp-
Presi [alaska-freegold.com]
Re:Deathtrap? (Score:2, Interesting)
In short, it can't land quick enough to avoid a 15 year-old kid with an RPG blowing a $68 million dollar hole in the taxpayer's wallet. Those who will have to ride in it view it as a death trap. The descent rate is slow enough to make even rifle fire a serious problem.
I heard that the osprey started out due to a delineation of service problem. That is, the Navy is not allowed fixe
Re:Deathtrap? (Score:2)
And how is this different from current helicopters? On the other hand, the V-22's much higher cruising speed and altitude will make it far less vulnerable to MANPADS and other anti-air weaponry than current helos.
Sure, the Osprey is not a
Re:Deathtrap? (Score:4, Informative)
That said, landing involves stopping, and is always risky. The V-22 has the ability to enter and egress an LZ faster and quiter than any other current rotary wing aircraft. I doubt many on
Re:Deathtrap? (Score:2, Informative)
Also the Navy actually has an extensive fleet of fixed wing aircraft. Quite a few are for transport
C-2A [fas.org]
C-9B [fas.org]
C-20G [fas.org]
C-40 [fas.org]
They also have quite a large collection of Cargo Rotary wing aircraft:
CH-53 [fas.org]
UH-60 [fas.org]
f
Re:Deathtrap? (Score:2, Insightful)
Too much we focus on the nay sayers, sometimes they are correct, but many times they are not. How many times were people told you couldn't fly, dive beneath the ocean, or go to the moon. All of which were wrong. Not only that, but the amount of injuries and deaths to get to those points is absolutely stagering and would not be tolerated in todays society.
Yet those things are what we define as great moments in our history.
Just because those things are decried by some people doesn't mean they ar
Some notes... (Score:4, Informative)
Vortex ring states are common to all rotary-wing aircraft. It involves a toroid-shaped volume of air surrounding the rotor disc, in which air pushed downward is recirculated into the top of the rotor disc, instead of pushing against the ground. All helo pilots are trained in how to avoid them and attempt to recover from them. It is a subject of thorough investigation in aerodynamics, and a problem inherent to every helicopter. What makes its presence in the V-22 significant is that even a mild vortex ring state in one of its rotors can cause a drastically sharp roll movement (due to uneven lift on both sides) that is very difficult to recover from.
"The B-1 bomber also suffered a number of crashes in testing."
The B-1B has also proven to be a hangar queen with tremendous operating costs, going against your point of "here are some aircraft which vindicated themselves in actual usage".
I do agree that tilt-rotor technology is the logical evolution of transport helicopters. This isn't just some novel "hey that's neat" offshoot of helos; this is the next generation of rotary-wing tech, something that will eventually replace Chinooks, Sea Knights, Mi-6's and the like.
Could be good for general aviation... (Score:2)
Re:Could be good for general aviation... (Score:2, Informative)
Re:Could be good for general aviation... (Score:4, Interesting)
Then it's a good thing the FCC has nothing to do with airworthiness certificates. ;-)
Re:Could be good for general aviation... (Score:2, Insightful)
Well when you have you have a 24 million dollar contract to develop a plane for the US Governemnt you can take that risk to develop two concept planes for them.
Damn those Aerospace Engineers (Score:4, Interesting)
I'm must be technically challeneged when it comes to understanding aerospace terms. But can somone please explain to me why this thing doesn't need an anti-torque mechanism (tail rotor). The advanced terms Boeing uses on the website make no sense to me.
By using a unique reaction-drive rotor system, the CRW concept eliminates the need for a heavier and more complex mechanical drive train and transmission, as well as the need for an anti-torque system.
Does this actually mean something, or is it just a bunch of big words to confuse the general public?
Re:Damn those Aerospace Engineers (Score:5, Informative)
A bit of both.
Conventional helicopters need a tailrotor because main rotor is spun by a mechanism that is fixed to the body of the aircraft which tends to spin the body around too. This thing seems to use a tip-jet mechanism to spin the main rotor, ie the tips of the blades contain little jet nozzles to spin it around and since it isn't mechanically fixed to the body it won't tend to spin the body around too.
Sorry if that didn't as much sense as i wanted it to, i haven't slept in 2 days.
oh so simple (Score:2)
dT = dL*cos(phi) - dD*sin(phi)
where (phi), is induced angle of Attack. also follow equation calculate Torque coefficient:
dQ = (dL*sin(phi) + dD*cos(phi))*r
and CT , CQ are
CT = T / ((Vtip)^2*A*density)
CQ = Q / ((Vtip)^2 * A * R* density)
http://aero.sharif.edu/~moayyedi/HeliA ero.html
A baby could have figured that out... um yea
Re:Damn those Aerospace Engineers (Score:3, Informative)
Ah, but that's exactly why it does make sense.
In a conventional helicopter, the rotor is spun by a driveshaft coming up into the center of the rotor. This creates a torque on the rotor, spinning it. By Newton's third law, there is an equal but opposite torque applied to the rest of the helicopter, causing it to rotate in the opposite direction. Thus, the tail rotor.
In the Dragonfly, hot gas is exhausted at the rotor tips, in a direction perpendicular to the rotor's ax
Re:Damn those Aerospace Engineers (Score:2)
It had some problems, too small, too slow, WAY too noisy (being a ramjet helicopter) too little fuel capacity, etc.
Re:Damn those Aerospace Engineers (Score:5, Informative)
It means that there's nothing inside the vehicle, cranking the rotor around, so the vehicle never tries to crank itself the other way.
Re:Damn those Aerospace Engineers (Score:2)
Yes, but wouldn't the friction between the spinning rotor and the rest of the aircraft still tend to spin the thing? Or is that friction negligible enough not to care?
Re:Damn those Aerospace Engineers (Score:2)
Re:Damn those Aerospace Engineers (Score:2)
The CRW I assume refers to their gearing system and how they control the aircraft in hover.
Which of course (Score:2)
Alternatively, of course, the XGP [amazon.com] has Sub-Ether drive and some fancy grappler arms.
6th day come to mind ?? (Score:2)
Re:6th day come to mind ?? (Score:2)
This technology has the potential to beat the pants off of the previous VTOL aircraft. I don't believe that it would replace the large fix-winged planes, due to the higher fuel consumption of vertical fight
X-50 half helicopter half plane (Score:2, Funny)
Re:X-50 half helicopter half plane (Score:3, Insightful)
Re:X-50 half helicopter half plane (Score:2)
Helicopters have a completely different problem, which is entirely due to their rotating lift surfaces. A fixed-wing aircraft has no fundamental block to going supersonic.
Plus, it's not like this craft needs great performance in VTOL mode. It would only be used for getting it off the ground and putting it back down.
Re:X-50 half helicopter half plane (Score:2)
Re:X-50 half helicopter half plane (Score:2)
I would have also guessed the way the exhaust is vectored even in jet mode might have something to do with it.. certainly that can't be efficient? although if the thrust figures you quote is what's coming out of the nozzle, rather than the raw engine output, your guess is as good as mine.
Lastly, you probably want to be judging based on empty weight, not max weight.
FWIW
Re:X-50 half helicopter half plane (Score:3, Informative)
Just a couple data points.
Wait a second.... (Score:2)
This rings a bell... (Score:2)
...isn't this the same kind of technology the Marine Corps uses to kill off excess 1st Lieutenants?
flight testing in 2002 (Score:2)
Did I miss something? The linked page says the testing was supposed to happen in 2002, yet here we are a few weeks away from 2004. For such a cutting-edge creation, you think they might have updated their web page, perhaps somewhere in the 2003 time-frame...
How do they transition? (Score:2)
A bit behind the times, really (Score:2)
Re:A bit behind the times, really (Score:2)
Go do some research. It's only a gryro until the rotors slow to ~25rpm and it exceeds 400 knots. Dumbass.
Time flys... (Score:2)
The second link points to the above qoute. Page is out of date by almost a year.
Hmmm...
Re:Time flys... (Score:3, Informative)
Wow. They've had a year to correct the typo "f light test" [boeing.com] (first paragraph, second sentence)?
Maybe they should switch their proofreading staff to metric.
deja vu (Score:2)
The airfoil... (Score:2, Insightful)
Re:The airfoil... (Score:2)
A teardrop shaped airfoil gives a better lift to drag ratio than one with fore and aft symmetry, but that one wouldn't work too good during the fixed-wing flight evolution. : )
Fairey Rotodyne (Score:5, Informative)
The Rotodyne was advanced technology for its day, but it was killed by the politicians.
Re:Fairey Rotodyne (Score:2)
Just like what Osprey today. I find the Osprey controversy interesting because it is not something divided among party lines, but knowledge lines. That is, people more knowledgable of its technology and capabilities support it, and those who are not aware do not support it.
Has anyone ever seen an interview with Moller? (Score:2)
They had an interview with Moller, inventor of the skycar. He's thge one that thinks we will all one day fly in car planes that vertically take off and use GPS to fly them safely.
Has anyone ever seen an interview with Moller and thought that you were looking at a con man? He has gotten over 200 billion (YES BILLION) over his lifetime in funding. All interviews
Re:Realistic commercial uses? (Score:2)
On the other hand, I can see quite extensive military uses for this aircraft, and I could see it as being a very important part of the military.
Maybe that is why DARPA is helping to develop it ;-)
Re:no faith whatsoever (Score:2)
Re:no faith whatsoever (Score:2)
spoke too soon (Score:2)
Re:spoke too soon (Score:3, Interesting)
It was about 25-50% more expensive then just buying the planes to begin with.
Re:spoke too soon (Score:2)
Re:Great technology (Score:2, Insightful)
That lesson being not to make sweeping judgements and generalizations based on publicity-driven artist's conceptions? Funny, I thought that (one of) the lesson(s) of the atomic bomb was that overwhelming force (when not guided by an idiot, not that I'm referring to a sitting politician or anything) can be used to end wars started by others.
Re:Great technology (Score:5, Funny)
Umm.... It's a military project. Maybe it's time we come to grips with the grim fact that military projects sometimes include missles.
TW
Re:Great technology (Score:2, Insightful)
Re:Great technology (Score:2)
Re:Great technology (Score:2)
Re:Great technology (Score:2)
Wow, talk about the ultimate telecommuting job. Sit at home, play "flight sims" and kill real people and GET PAID FOR IT! Sounds like the movie Toys, only real! (Throws out his Bf1942 cd)
Re:Great technology (Score:2, Funny)
Would you rather have them drop Britney Spears CDs on the enemy? ..... Naw... Too Cruel.
Re:Great technology (Score:2)
-Albert Einstein
It's a Nerf missile. (Score:2)
Re:Great technology (Score:2)
How many pacifist societies exist on Earth? (not very many) How many of them have neighbors who compete with them for resources? (zero)
Re:Is this going to kill the Moller sky car ? (Score:2)
Don't bring up Moller again.
First flight and production of his machines has been 'imminent' for the last, what? 15 years or so?
Ever heard of the term 'vaporware'?