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October 14, 2007 10:50 AM   Subscribe

So You Think The V-22 Is Ridiculous? [previously] Let me present you its dumb brother, the DuPont Aerospace DP-2. (No relation to the chemical conglomerate).

Although successively panned in reviews by the US Navy in 1986, and DARPA in 1990, and shifted to the Office of Naval Research when DARPA uncharacteristically refused in 1997 to spend its allocated funds, the DP-2's protracted development has kept receiving Congressional earmarks for over twenty years, supported by Representatives Duncan Hunter (R.-Calif.) and Dana Rohrabacher (R.-Calif.), as well as former Representative Christopher Cox (you guessed it...R.-Calif.), nowadays Chairman of the Securities Exchange Commission.

Hunter, in particular, has steadfastedly defended the contraption, despite some slight design flaws, like that of incinerating soldiers. His support, however, may have less to do with the alleged ability of the concept than with the equally steadfast campaign funding he has received from DuPont.

This month, however, the efforts of DuPont, Hunter, Cox and Rohrabacher have finally been rewarded with a first successful (tethered) hover. It may however be too late.
posted by Skeptic (18 comments total) 3 users marked this as a favorite

 
Yipes. Looks a bit like the Yak-36 and Bell X-14 concepts with the forward-mounted engines. Wouldn't like to be anywhere near that thing when it's trying to hover.

V/STOL is incredibly difficult to do properly - just take a look at the various attempts there have been to build V/STOL aircraft, and see how many you recognise - the rest are the ones that failed:
V/STOL Wheel
posted by Nice Guy Mike at 11:26 AM on October 14, 2007 [1 favorite]


--->
----> AIR
--->
posted by trinarian at 11:43 AM on October 14, 2007 [1 favorite]


Nice Guy Mike: I'm an aeronautical history nut, and I'm thus familiar with most of those designs, in particular with those that failed. Few of them, however, strike me as so fundamentally stupid flawed as the DP-2 (OK, perhaps the tailsitters). Its designers don't even seem to have considered the pilot's need to see the spot where he's supposed to land the thing!
posted by Skeptic at 11:48 AM on October 14, 2007


relies on two turbojet engines mounted in the forward section of the fuselage for both lift and forward thrust

NASA Ames used to have this test jet that they'd occasionally show at air shows that had the jet exhaust go over the wings, so you would get lift at very low speeds. The plane had a very short take-off and landing capability that was amazing to see. The NASA experiment was just a slight modification of a normal aircraft and didn't seem terribly risky or unstable.

From the description it sounds like they are using some of these concepts, but are trying to make it a Vertical take-off and landing craft, which is much harder and more dangerous to do (as all its failures seem to show).

Boeing, Lockheed and Grumman did not invest in his concept of the DP-2 aircraft because they were skeptical of his ability to actually achieve success.

This tells you much because these companies are normally all too happy to take government research money. They must really think it is a bad idea.
posted by eye of newt at 12:08 PM on October 14, 2007


It demonstrates the great demand for vertical capabilities. The money to be made on a safe aircraft that can deliver a humvee or a howitzer over a long range is the money saved from maintaining half of the navy. I liked the winged airship concept disclosed recently, but what a target it would be.
posted by Brian B. at 12:52 PM on October 14, 2007


I think the machine did exactly what it was supposed to.
posted by kuujjuarapik at 12:58 PM on October 14, 2007


suck up twenty years' worth of taxpayer funds?
posted by stenseng at 1:57 PM on October 14, 2007


yep, and blow smoke.
posted by kuujjuarapik at 2:02 PM on October 14, 2007


I dont know anything about this stuff but this Vangaurd Omniplane is pretty great looking.
posted by damn dirty ape at 2:22 PM on October 14, 2007


This is link is Mark Deadrick (started with program in 1988) on the duPont Aerospace DP-2 Program
June 12, 2007. He doesn't leave much doubt that this a faliure that has the potential to kill air crewsl. The Osprey has already killed people and will kill more.
posted by Rancid Badger at 6:11 PM on October 14, 2007


$63 million ! Why, you can't even get a bridge built in Alaska for such a low amount.

Given the amount of money the Pentagon spends on R&D every year, this amount doesn't even rate a footnote.
posted by davebarnes at 6:19 PM on October 14, 2007


Thanks Skeptic for this post.
posted by intermod at 7:47 PM on October 14, 2007


Its designers don't even seem to have considered the pilot's need to see the spot where he's supposed to land the thing!

On neither the Harrier nor its replacement, the F-35B, can the pilot see the landing spot. That's not the problem. The fundamental problem is that directing the thrust down really isn't a very efficient method of achieving VTOL. It works, just barely, for the Harrier; the F-35B achieves vertical lift with a much more efficient lift fan.

If you are looking at small-scale troop movements (insertions and extractions), the X-Hawk has a much better shot at success.
posted by Doohickie at 9:41 AM on October 15, 2007


Flying soldiers into combat in one of these pork-laden boondoggles is just stupid when you can simply roll them in (or even float them over rivers) in a safe, efficient M2 or M3 Bradley Fighting Vehicle!
posted by Pollomacho at 9:54 AM on October 15, 2007


On neither the Harrier nor its replacement, the F-35B, can the pilot see the landing spot.

Very true.

The fundamental problem is that directing the thrust down really isn't a very efficient method of achieving VTOL. It works, just barely, for the Harrier; the F-35B achieves vertical lift with a much more efficient lift fan.

Well, that depends how you define "efficient". I'd say the Harrier is just about the single most efficient VTOL aircraft design because it works by directing the thrust straight down - i.e. the engine if uses to operate in the VTOL regime is the same as that used for normal flight. The F-35B is less efficient in the sense that it lugs a bloody great vertical lift fan, clutch and drive shaft which are used for only a tiny fraction of the flight. In the sense of making use of the weight you're carrying into the air, Harrier can use 100% of it's engine-related weight in the hover, and nearly 100% of it in forward flight.

Why, then, was the X/F-35 chosen over the X/F-32 to fulfill the JSF requirement, when the X/F-32 would use directed thrust for lift in a similar manner to Harrier? Because VTOL is all about tradeoffs and compromises. Hot gas ingestion and ground environment, for example, are better with the forward-mounted lift fan compared to Boeing's pure jetborne design, to name just a few.

Sorry, I could write a hell of a lot on this topic, but I don't want to bore you...
posted by Nice Guy Mike at 10:14 AM on October 15, 2007


The same engine on the X-32 could not lug the weight of a supersonic aircarft into the air; to achieve vertical flight, Boeing had to remove the inlets that permitted supersonic flight.

The X-35 was able to hover at less than 70% throttle in a configuration that could fly at supersonic speeds.

And while the Harrier was the most efficient VTOL design when it was introduced, it was never a supersonic aircraft.

That's what I mean by "more efficient."
posted by Doohickie at 11:52 AM on October 15, 2007


The same engine on the X-32 could not lug the weight of a supersonic aircarft into the air; to achieve vertical flight, Boeing had to remove the inlets that permitted supersonic flight.

True. The X-35 has more vertical thrust in hover mode and the X-32 was somewhat overweight - it wasn't just the supersonic cowl they had to take off to get it to hover, it was stuff like, ooh, hydraulics to raise the undercarriage.

The X-35 was able to hover at less than 70% throttle in a configuration that could fly at supersonic speeds.

Not sure about 70%. Where's that from?

And while the Harrier was the most efficient VTOL design when it was introduced, it was never a supersonic aircraft.

Again, very true. Remember, the Harrier was originally designed as a short-ish range Close Air Support (CAS) aircraft that could be operated from short, damaged and outright unprepared strips in the event of a Soviet invasion of Europe that damaged or destroyed NATO airbases. It had no need to be supersonic, and the wide diameter Pegasus turbofan engine meant it would struggle to get there. You can actually drive a Harrier supersonic, but only in a dive, with no stores attached, and you'll be breaking limits if you do so... I certainly wouldn't recommend it...

F-35 is a completely different beast, an interdictor/strike aircraft (one that is nevertheless capable of CAS and air-to-air) designed for expeditionary warfare from small ships as well as from shorter runways.

That's what I mean by "more efficient."

In that case, I'd say you meant it's "more capable".
posted by Nice Guy Mike at 12:54 PM on October 15, 2007


For funny-looking aircraft, may I commend to your attention the Airbus Beluga.
posted by ikkyu2 at 9:53 AM on October 16, 2007


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