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Old 1st October 2005, 06:22   #81 (permalink)
 
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revolutionary,

I honestly believe the V22 will (and probably does) fly quite nicely, and so will the 609. There is no way the folks at Bell will let it fly so poorly as to be unpleasant.

The other points will be solved, as well, like the hydraulics and complexity, so that in the end it will be expensive to run, but not unsafe, I think.

What cannot be fixed is the payload disadvantage it suffers with regard to helicopters. It will carry only half the load of an equivilent helo, no matter what magic is used, as long as that same magic is allowed to be used on the helo. In the end, customers will decide if the cost is worth the speed, but the fundamental handling will not be a determinent, I think.
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Old 1st October 2005, 07:08   #82 (permalink)
 
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Mart,

Quote:
"Tiltrotor will never be as efficient in hover, but counterrotor is unlikely to be as efficient in high speed flight."
They both have latterly located counter-rotating twin main rotors. The concern is; which configuration can significantly improve high-speed flight without jeopardizing hover (payload).

The primary differences between the tilt-rotor configuration and the ABC-rotor configuration are the means of propulsion and the means of lift.

Tilt-rotors ~
~ Hover ~ Uses the rotors.
~ Forward flight ~ Uses the rotors (props) for propulsors, and separate wings for lift.
~ The prop/rotors are not ideal as rotors nor are they ideal as propellers.

ABC-rotors ~
~ Hover ~ Uses the rotors.
~ Forward flight ~ Uses separate props for propulsors, and the rotors as wings.
~ The ABC-rotors are not ideal as rotors nor are they ideal as wings.

For reasonable fast forward flight, my money is on the ABC-rotors over the tilt-rotors.

For very fast forward flight, my money is on Reverse-velocity-rotors over the tilt-rotors. It will be a lot easier to produce a craft with reverse-velocity-rotors and fan-jets then trying to morph the tilting rotors into fan-jets during transition.

The next question then becomes Coaxial, Interleaving, Intermeshing or Side-by-side?
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Old 1st October 2005, 19:38   #83 (permalink)
 
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"For reasonable fast forward flight, my money is on the ABC-rotors over the tilt-rotors."

Agreed, but there are many dynamic and mechanical problems to overcome first.

"For very fast forward flight, my money is on Reverse-velocity-rotors over the tilt-rotors."

Agreed that seperating thrust and lift function allows the optimum design and diameter (as you pointed out) of each system.

"The next question then becomes Coaxial, Interleaving, Intermeshing or Side-by-side?"

Well, pure interleaving is still on shakey ground, for same reasons as V-22. I would wait to see how Sikorsky get on, regarding rotorwash dynamics, and keep Stepniewski intermesher in mind.

Mart
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Old 1st October 2005, 21:36   #84 (permalink)
 
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Angel

Your own tilt-rotor?

VTOL airplane with only one tiltable prop-rotor. Then click on [Images].
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Old 2nd October 2005, 00:25   #85 (permalink)
 
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Nick,

Some items on that list, such as the vulnerability of hydraulic and mechanical lines, could be fixed, I agree. But the assymetrical VRS problem and the near impossibility of autorotating are things that are inherent in the design and will never completely go away.

We all want a faster ride but maybe we should just accept that helicopters are slower than airplanes, just as wheelbarrows are slower than motorcycles, and stop trying to crossbreed aircraft types.

I mean, you don't see anybody trying to mate a wheelbarrow to a motorcycle to speed up backyard chores, do you?
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Old 2nd October 2005, 01:54   #86 (permalink)
 
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IMHO

[Very fast 'rotorcraft' flight] will require [Reverse velocity blades] will require [Large active blade twist].

[Large active blade twist] will allow the use of the Interleaving configuration; with its low disk loading, short rotor-to-rotor span, and negligible downwash on the fuselage.

Propelled by turbo-fan engines.



Last edited by Dave_Jackson : 2nd October 2005 at 02:11.
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Old 2nd October 2005, 17:04   #87 (permalink)
 
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Quote:
I mean, you don't see anybody trying to mate a wheelbarrow to a motorcycle to speed up backyard chores, do you?
Well...
Muck-Truck
Haulz-All
Dr. Powerwagon
Hey, you asked!
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Old 3rd October 2005, 04:18   #88 (permalink)
 
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Flingwing207,

Nice one... I stand corrected. But, does the Muck Truck do 0-60 in 4.5 seconds? I mean, we're talking about speeding up backyard chores, not just about motorizing 'em.
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Old 4th October 2005, 15:03   #89 (permalink)
 
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Hey it's only a matter of time before you see something turn up on one of The Discovery Channel's plethora of modder shows - perhaps "The Kustomizer" (currently turning a scrapped S-61R into a luxury limo-coach).

Last edited by Flingwing207 : 4th October 2005 at 15:40.
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Old 21st October 2005, 23:23   #90 (permalink)
 
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V22 Osprey

SO Bell/ Boeing are not gonna submit a CSAR X bid for the V-22 , I guess you don't get too many points for exceeding the requirements .

http://www.shephard.co.uk/rotorhub/D...f-c82e586e9d1a
Bell issued the following statement late Thursday:-

The Bell-Boeing V-22 team has made the decision to not submit a proposal for the U.S. Air Force CSAR-X competition.

Quote attributed to Bob Kenney, vice president of the V-22 joint program

"After thorough review of the revised Air Force request for proposal, it was clear that the CSAR-X program's requirements and funding profile did not call for the advanced speed and range offered by the V-22 Osprey, and instead leaned toward capabilities found in more-traditional helicopter-type aircraft.

"The V-22 continues to excel in its role of deep-strike combat insertion and search and rescue for the Air Force Special Operations Command and expeditionary medium-lift for U.S. Marine Corps, offering unmatched capabilities for these missions. We continue to focus on these customers to ensure we meet our commitments to them."
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Old 22nd October 2005, 04:02   #91 (permalink)
 
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Nick,

What am I missing here?


Quote:
"The V-22 continues to excel in its role of deep-strike combat insertion and search and rescue for the Air Force Special Operations Command
Please explain to the unwashed of us what the difference between CSAR-X and Search and Rescue for Air Force SpecOps is?

Seems the selling point of the Osprey has been amongst others....SAR capability....and now they do not care to compete for the CSAR-X program?
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Old 22nd October 2005, 10:17   #92 (permalink)
 
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So the only thing the V-22 will be any good at, is the high speed insertion of a small SF group where time is critical?
Lot of money for one mission...
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Old 22nd October 2005, 14:26   #93 (permalink)
 
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....or a Vertical Envelopment USMC style where anything bulky at all has to be hauled on a sling....no Humvees inside...no Howitzers inside...wonder how fast they haul things that way as compared to the helicopter?

How does one spell P-O-L-I-T-I-C-S?
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Old 22nd October 2005, 14:48   #94 (permalink)
 
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I hate to burst the bubble but the CV-22 will do the mission just fine. Just as it was said, "don't believe the hype", I can say don't believe the negative hype either. It flies and operates quite well actually. Does it have problems, yes, but they're not nearly as dramatic as some folks want you to believe.
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Old 22nd October 2005, 15:39   #95 (permalink)
Gatvol
 
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Quote:
How does one spell P-O-L-I-T-I-C-S?
Come on Sasless, thats Texas T........How else can some EEElected official work for 50k a year and be a Millionaire in 4 years.......... Simplfy the word. B-E-L-L.
Dont forget all those surplus aircraft that hit the crusher?? Thank you B-E-L-L
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Old 22nd October 2005, 16:29   #96 (permalink)
 
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mckpave,

No bubble burst yet, mckpave, untill you give us a reason to believe you. Who are you, what do you know? If it does the mission fine, as you say, when will we see someone actually hoisted into it? It has been 20 years so far in development, and the hoist isn't even fitted.
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Old 22nd October 2005, 16:44   #97 (permalink)
 
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Other than very small helicopters like the Robbies and maybe a 206, is there a helicopter that does not have a winch/hoist fitted at some time?
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Old 22nd October 2005, 17:53   #98 (permalink)
 
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Cool

Winch on a 206? Yep. Many years ago PHS in Oz used to do training with the Jetranger and a winch. State of the art rescue machine back then.
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Old 22nd October 2005, 20:20   #99 (permalink)
 
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Angry

BigMike said;
Quote:
So the only thing the V-22 will be any good at, is the high speed insertion of a small SF group where time is critical?
Nothing will be as good as the V-22 for defeating the NeoCon's worst enemy.


What other craft can get the General, his propagandist, and the embedded reporter to the scene and back, before the 6:00 news?
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Old 22nd October 2005, 20:41   #100 (permalink)
 
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Is this OGE hover?

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