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Old 1st Jul 2013, 17:16   #21 (permalink)

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Perhaps the Rotordyne design could have prevented the development of the Osprey had it gone into Production.
Shame it didn't. It had a very impressive payload/empty weight ratio. Far better than some other more recent projects in the US of A.......
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Old 1st Jul 2013, 17:52   #22 (permalink)
 
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Shame it didn't.
I'm not sure you would want the "bad guys" knowing you were approaching for about 10 miles with the volume of those tip jets...not to mention I really question the manuverability of the rotodyne in forward flight.
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Old 1st Jul 2013, 17:54   #23 (permalink)
 
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Nice to see the interest in this...but please note Rotodyne had no R in the middle!
Anyway,three follow up points
1) When the Helicopter Museum collected a test blade from Aston Down airfield many moons ago they also collected a number of tipjet silencer units,which had been trialled on the blade(attached to a whirl tower). The story goes that these noise tests were actually connected to Rolls Royce work silencing the noise levels of the Viper engines on the HS125 corporate jet but previously had demonstrated significant noise reduction in the Rotodyne application. Certainly the evidence is that by the time of the cancellation the noise issue was much less of a show stopper.
2) Physically moving the blade was and still is a major challenge.It is so heavy as to require about 8 -10 strong men to lift it.....even moving one of the blade arms is a six man job.....so weight was a big issue. Today with modern composites it would be so much more viable.
3) There was another factor in the early 1960s that led to cancellation and that was that when Westland took over Fairey and the Bristol helicopter division,they had three" heavy lift" helicopters on their books but only one had any orders,the Belvedere. As they couldn't afford to develop all three ,the Rotodyne and the Westminster were abandoned. Big mistake in retrospect as the Belvedere never amounted to much( another story of poor government investment when you look at the Chinook story ) and the Westminster also could have been very successful ......perhaps subjects for new threads at some other time?
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Old 1st Jul 2013, 17:54   #24 (permalink)

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The tips jets were only lit up for takeoff and landing.
Not forgetting that you can feel a Chinook coming from almost ten miles away.
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Old 1st Jul 2013, 19:22   #25 (permalink)
 
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At least we know where the SK Blackhawk got its design idea from......



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Old 2nd Jul 2013, 05:44   #26 (permalink)
 
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Sasless.....actually the Westminster used a dynamic system based on the experimental Sikorsky S-60, which itself was developed from the earlier S-56 Mojave with big outrigger radial piston engines. Westland installed two Eland turbines and built up the airframe as a testbed.Later the principle went back across the Atlantic to emerge as the S-64 Skycrane.
Two Westminsters were built and both were scrapped ,ending up as tie rods under a concrete platform at an industrial site in a village near Yeovil!

I see the Rotodyne in the background of the picture.......
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Old 2nd Jul 2013, 13:57   #27 (permalink)
 
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The tips jets were only lit up for takeoff and landing.
Or any amount of hover/loiter, correct?

Come to think of it, what was the rotodyne's hover performance like?
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Old 2nd Jul 2013, 22:43   #28 (permalink)
 
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Come to think of it, what was the rotodyne's hover performance like?
F'in noisy!

hat, coat.

slinks off to read "meccano Magazine " articals,July and November 1958, covering the Rotodyne and it's appearance at Farnborough, that year.
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Old 2nd Jul 2013, 23:37   #29 (permalink)
 
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Originally Posted by SansAnhedral View Post
Or any amount of hover/loiter, correct?

Come to think of it, what was the rotodyne's hover performance like?
33,000lb payload

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Old 2nd Jul 2013, 23:54   #30 (permalink)
 
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Interesting stuff, considering it was a 1950's experimental design. This video certainly demonstrates the capability and also the post war attitudes toward flying: gear activation in the hover being just one instance!

The tip jet noise was horrendous but was being sorted: silencers were under development to reduce tip jet noise to below that generated by the blades themselves, but politics involving the UK aircraft industry in the 1959-60 era consigned many a promising company and project to the scrap heap. Rotodyne was just one of them which (if fully developed) had the potential to change the course of rotorcraft operations.



Flight magazine had a 1957 article which is also worth reading: remember, this was 56 years ago in answer to a Fairey proposal in 1946 followed by a BEA specification issued in 1951. What amazing foresight and vision, if only we had the like of that in these risk averse times
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Old 3rd Jul 2013, 00:09   #31 (permalink)
 
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The History channel had a programme on the Rotodyne: in the fourth of these clips it's interesting that on one of two flights into Battersea, the noise measuring down in the street couldn't detect the tipjets above the surrounding traffic noise!







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Old 16th Aug 2013, 15:25   #32 (permalink)
 
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George Hislop - Telegraph
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Old 16th Aug 2013, 22:55   #33 (permalink)
 
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Out of interest, a modern American company tried to redo the concept quite recently and even had DARPA involved. Unfortunately they ran out of money and also DARPA have gone with a more complex compound aircraft design that has extending blades.
They have instead had a recent injection of cash from the Chinese and have come up with a couple of rather nice autogyro designs instead.
Home - Groen Brothers Aviation Global, Inc.

Cheers now
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Old 17th Aug 2013, 00:19   #34 (permalink)
 
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Kinda, sorta like the Rotodyne rotor:

http://sitelife.aviationweek.com/ver...ec302.Full.jpg
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Old 19th Aug 2013, 13:48   #35 (permalink)
 
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OG

The Groen Bros machine was much more akin to the CarterCopter demonstrator rather then the tip-jetted Rotodyne. Plus, Jay Carter's machine has been built and is actually flying, even having broken the Mu = 1 boundary a few years back.
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Old 19th Aug 2013, 14:35   #36 (permalink)
 
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The problem with Groen products is that the company has no money [subject to this supposed Chinese interest] so everything they present is 'What if...?'

It has been like that for a long time and they are therefore just one of dozens of companies across the world producing paper aeroplanes for the ephemera market.... and the autogyro industry has more than its fair share.

The favourite ploy is to design something really smart and stick POLICE signs on it..... as if that makes them work much better!
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Old 19th Aug 2013, 18:09   #37 (permalink)
 
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Sans,
Please correct me if I'm wrong, but I understood the Groen (DARPA) machine to be a "tip jet" aircraft. The Carter copter family use a heavily weighted tip to produce extra inertia when spun up, so the aircraft can't hover but it does do impressive jump takeoffs.
One of the proposed uses for the DARPA aircraft was long range SAR which would have required a hover capability, possible only with a fully driven main rotor.
I have seen the videos of the new prototype Carter machine and it is a real cracker though.

Cheers now
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Old 19th Aug 2013, 18:42   #38 (permalink)
 
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PA News....how could you be so cynical? If the banks think its a great idea and part with the money surely its gonna work!!
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Old 19th Aug 2013, 20:24   #39 (permalink)
 
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OG

You are correct, I missed your reference to their DARPA specific program (as opposed to their Hawk series craft) My mistake!
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Old 19th Aug 2013, 21:06   #40 (permalink)
 
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Sans,
No probs.
My current favourite contender for most innovative compound aircraft is this beauty.
http://cdn-www.airliners.net/aviatio.../0/2160079.jpg
I really hope they develop this into a production aircraft. Its not as simple as a tip jet type or plain gyro, but it looks awesome; and it shifts. One wonders if they are using some of the Carter technology under licence, like the slowed rotor.

Cheers now

Last edited by oldgrubber; 19th Aug 2013 at 21:08.
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