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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.
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First Hover Flight Test of X-50A Dragonfly

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  • by teklob ( 650327 ) on Saturday December 06, 2003 @12:55AM (#7645615)
    The poll predicted flying cars within our lifetime.
    That sure was fast...
  • Deathtrap? (Score:3, Insightful)

    by The Snowman ( 116231 ) * on Saturday December 06, 2003 @12:58AM (#7645632)

    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)

      by bellers ( 254327 ) on Saturday December 06, 2003 @01:07AM (#7645683) Homepage
      Incidentally, the Osprey program this week just surpassed 1000 flight hours for the program. It's racked up lots more flight time since the grounding and reengineering interval from 18 months ago.

      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.

      • 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.

        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)

          by el_guapo ( 123495 ) on Saturday December 06, 2003 @09:29AM (#7647057) Homepage
          whilst it is entirely true that they're FRAGILE (ie: you can shoot most down with a pistol), they are FAR from "flaky". aside from the fragility issue, they are no different from fixed wing aircraft in their "flakiness". they simply trade high speed for the ability to hover, that is ALL. and, incidentally, there is no fix for the speed issue in a conventional chopper, at some "N" speed, the retreating rotor blade stalls and the bird flops over.
          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)

          by Moofie ( 22272 ) <{lee} {at} {}> on Saturday December 06, 2003 @10:35AM (#7647263) Homepage
          Uh, so how many Marines can you deliver into hostile territory with an A-10?

          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.
    • The most brain-damaged aircraft I've ever seen.

      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
      • "Look at what we do with the air superiority we have now... bomb this shit out of people who can't defend themselves."

        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.
        • I don't think anything will ever replace the titanium bathtub for close air support. Those things are amazing. They can take a beating, kill a tank, yet can fly slow enough to kill infantry with the vulcan cannon.
          • There was one in the first gulf war that got hit by a cheap surface to air missle, lost 2 out of 3 wing spars and half the wing skin, yet made it back to base and was repaired and bombing again 48 hours later.

            Or so I remember reading.
          • They won't be able to take a beating from modern AAA and SAMs. The A-10's reliance on "absorbing" damage is not something that will work against modern and next-generation weapons such as the S-300 and S-400. Weapons that the A-10 has yet to be used against, and in a potential WW3, very well may have to deal with.

            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
      • by Laur ( 673497 )
        You do know that there are three different versions of the JSF don't you, a conventinal one for the AF, a carrier version for the Navy and the Marine STOVL version. They will share many common parts, making them cheaper than three separate planes, but will still be very individualistic.

        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

        • The lift fan works well in a brand new unit that has seen at best a few hours of flight time. Just think about this thing being deployed overseas, going through hundreds of missions, in the baking heat, in the bitter cold, exposed to sea air with its humidity and high salt content.

          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
          • The Marines need close air support, because historically the Air Force and Navy haven't been willing to give it to them. One might argue that the current joint doctrine will get rid of this objection, but one also might argue that a Marine Expeditionary Unit is a very handy self-contained air and land fighting force.

            Different problems require different solutions.
          • 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?

            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
        • You musta not read any of my posts, then.

          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
        • The initial test was amazing, the plane literally shot up 20 feet!

          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

        • Not to mention the Harrier must carry water to cool it self during hover. Most people don't realize that you can only hover something like 2-minutes MAX (don't hold me to that may be smaller) before you must refill the water container. Once the water is used up, the Harrier will destroy it self should it attempt to hover again. Furthermore, it uses a large amount of water which could otherwise be used for weapons or even more fuel. Something like 50 or 100 gallons of water means you could be
      • You're clueless about how the whole JSF project works, aren't you?

        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).
    • Actually, the Osprey is a fantastic aircraft and I would argue that they took the best features of both types of aircraft when the tilt rotor craft was created (btw, the Osprey is not even close to being the first tilt-rotor... they date back about 30 years, it is just the first military application). Anyway, there have been two mishaps in the V-22 program. One was due to vortex-ring state, a phenomena that was not an engineering issue, but rather a poorly understood aerodynamically phenomena that is more
  • They don't need as much speed as was quoted in the article. (500 kts) It would be intresting as a cheap, sub 200K range private general aviation plane. I'm surprised Boeing is taking a risk though with such a strange new craft, especially with their current financial troubles.
  • by MikeDawg ( 721537 ) on Saturday December 06, 2003 @01:04AM (#7645667) Homepage Journal

    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?

    • by SupaMegaBuffalo ( 717226 ) on Saturday December 06, 2003 @01:09AM (#7645692)
      Does this actually mean something, or is it just a bunch of big words to confuse the general public?

      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.
    • by bellers ( 254327 ) on Saturday December 06, 2003 @01:10AM (#7645700) Homepage
      It means that the reaction gases generated by the turbine engine are routed out through the rotors and to the rotor tips, making them move.

      It means that there's nothing inside the vehicle, cranking the rotor around, so the vehicle never tries to crank itself the other way.

      • the vehicle never tries to crank itself the other way.

        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?

        • It may be not enough to care, but if it is non-negligable, a small amount of the turbine's air output could be routed to a little nozzle on the back of the plane pointing sideways (in addition to the nozzles on the tips of the rotors and). You still wouldn't need a complex series of mechanical linkages to drive a secondary propeller.
    • Actually it pretty much works in the same say that the CH-47, and CH-46 work, counter rotating propellers.

      The CRW I assume refers to their gearing system and how they control the aircraft in hover.

  • Is not the same thing as Draganfly [] Which has four rotors that do not rotate into the shape of a fixed wing aircraft. and no, sadly there's no X-50A Drive.

    Alternatively, of course, the XGP [] has Sub-Ether drive and some fancy grappler arms.
  • Isn't this aircraft basically the same thing as in the movie "6th day" ?
    • That's the first thing that came to my mind too. I think that the 6th day (like Minority Report) did a lot of "fishing" (if you will) for technologies which we might see in our lifetimes, cars that drive themselves, holographic girlfriends, that airplane, in addition to the story driven tech (cloning).

      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

  • It's intended to float like a butterfly, sting like a bee. I guess but what I enjoy about this new type of airship is the fact it is combining the best of different technologies. To create an interesting new. A supersonic helicopter anyone?
    • I doubt we'll see any supersonic helicopters any time soon. Harriers can't even go supersonic. It would be one hell of an engineering feet to build a rotary-to-fixed aircraft like the X-50 and work supersonic flight into it's capabilities.

      • I don't think there's anything that makes a supersonic Harrier impossible; it just doesn't have the engine power for it.

        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.
        • What I can't figure out is WHY the Harrier's max speed is so slow. It's got about 80% (22K lbs vs 27K lbs) of the thrust of an F-16 and it's max weight configuration is almost 50% lighter (10K Kilos vs 16K Kilos) yet it's max speed is around 1/3rd (550 knots vs 1,500). What is the factor limiting the Harrier to such slow speeds?
          • IANAaerospace engineer, but I'd guess it's the mostly the aerodynamic profile -> drag; the Harrier is many things but sleek it is not.

            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.


      • The F-35C can go supersonic, and I think the Yak-141 can as well.

        Just a couple data points.
  • Didn't the Fantastic Four have a jet like this?
  • ...isn't this the same kind of technology the Marine Corps uses to kill off excess 1st Lieutenants?

  • After completing load testing of the rotor, the CRW will be ready for first flight, which is expected to occur by the end of 2002.

    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 from hover to fixed wing? Those rotors must get a lot of momentum, surely it takes time to slow them down and lock them into place, and then to spin them up for landing. I don't suppose they can just let the thing drop like a stone in the meanwhile?
  • The CarterCopter [] has had proven VTOL flight with small canard-style wings for several years now, even a demonstration at Oshkosh. Boeing's a bit behind the ball on this one.
  • After completing load testing of the rotor, the CRW will be ready for first flight, which is expected to occur by the end of 2002.

    The second link points to the above qoute. Page is out of date by almost a year.

    Hmmm... ...wish'em luck!
  • I swear I saw something like this almost 20 years ago. I was watching some show on late night TV in Washington state, and the really cool thing on it was an aircraft with a stubby-bladed rotor that could be fixed as a wing for jet-propelled flight. I haven't heard anything like that since. I guess it took them a long time to work out the bugs.
  • How are they going to make the airfoil symetrical for fixed-winf flight? Wouldn't one half of the wing be facing in the right direction, and the other half be "backwards"? It didn't mention this in any of the links as far as I can tell. The only solution I can think of is a symetrical airfoil from front to back.
    • You can make a symmetrical airfoil. Stick your hand out a car window and tip it upwards. The cross section of your hand is more or less symmetrical, but you can still generate lift, by increasing the angle of attack.

      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)

    by dubstop ( 136484 ) * on Saturday December 06, 2003 @05:19AM (#7646525)
    The Fairey Rotodyne [] was built nearly fifty years ago. Like the Dragonfly, it used (what was then called) tip-jet rotors, so there was no need for a counter-torque rotor on the tail.

    The Rotodyne was advanced technology for its day, but it was killed by the politicians.
    • "The Rotodyne was advanced technology for its day, but it was killed by the politicians."

      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.
  • I recently saw a History Channel show where they were showing how sci fi often becomes reality. (I believe it was the show Greatest Movie Gadgets)

    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

What this country needs is a good five cent ANYTHING!