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Author Topic: Doman helicopter projects  (Read 11490 times)

Online hesham

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Re: Doman helicopter projects
« Reply #15 on: May 14, 2013, 05:29:46 pm »
Great find Stargazer,


but I know only the D-11,obviously this is a new one,and may be
it was RPH or R/C model,I will check about it.

Offline Mark Nankivil

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Online hesham

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Online hesham

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Re: Doman helicopter projects
« Reply #18 on: January 06, 2016, 09:32:55 am »
I recently came across this very lousy picture of a 1958 helicopter refered to only as the Doman D-12.

Has anyone heard of this one before? It could be a small R/C model of course, but it could also be a genuine prototype. Hard to tell given the poor quality here...

From Aviation Week;

http://archive.aviationweek.com/search?QueryTerm=DOMAN+D-12

« Last Edit: January 06, 2016, 09:40:53 am by hesham »

Online hesham

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Re: Doman helicopter projects
« Reply #19 on: April 23, 2016, 08:42:47 am »
Hi,

does any one hear about Doman BD-68 design ?.

Offline Apophenia

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Re: Doman helicopter projects
« Reply #20 on: April 24, 2016, 08:43:04 pm »
does any one hear about Doman BD-68 design ?.

The Berlin Doman BD-68 was to be a three-engined development of the Doman D-10B.

Online hesham

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Re: Doman helicopter projects
« Reply #21 on: April 25, 2016, 04:40:18 am »
Many thanks to you my dear Apophenia.

Offline Skyblazer

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Re: Doman helicopter projects
« Reply #22 on: May 23, 2016, 11:05:03 am »
From Aviation Week

Thanks, hesham. Since my initial question, I'd found some more on the D-12, which was called the Whippet:

Offline Skyblazer

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Re: Doman helicopter projects
« Reply #23 on: May 24, 2016, 03:15:33 am »
 

Looks like a Dolman design to me

Yep. This was the Doman LZ-4, a research and development helicopter. More about it here:

Quote
In 1945, Glidden S. Doman formed Doman Helicopters Inc. in order to develop various helicopter engineering concepts. These included a new hub system which was essentially similar to the mechanism used on a variable pitch propeller. The rotor system also incorporated a gimbal mounting to provide the necessary tilting of the rotor disc. Doman's theories were tested initially by installing an experimental system on a USAF Sikorsky R-6. This helicopter was known as the Doman LZ-1A and it started flight tests in early 1950 with remarkably good results. It was followed by the larger LZ-2A Pelican.

Doman's system was then designed into a larger helicopter that was seen as a viable commercial production machine. The LZ-4A had a capacious fuselage with three rows of double seats in the main cabin and a two-crew flight deck in front. Large folding doors provided access for loading bulky cargo into the main compartment. The tail boom was conventional with a cranked-up rear section mounting a tail rotor, and the LZ-4A sat on a four-leg undercarriage with trailing link dampers. A 400hp Lycoming SO-590-B engine was positioned in the lower nose, driving the four-blade rotor via a flexible transmission. Following its first flight in November 1950, and subsequent testing, Doman moved on to the improved LZ-5 and transferred the LZ-4A (N74147) to Curtiss Wright as a test vehicle.
Source: R.Simpson "Airlife's Helicopter and Rotorcraft", 1998

Technical data for LZ-4
Number of seats: 8, engine: 1 x Lycoming SO-590-B rated 400hp, rotor diameter: 14.64m, length: 11.7m, height: 3.41m, gross weight: 2165kg, empty weight: 1343kg, cruising speed: 125km/h, rate of climb: 244m/min, absolute ceiling: 4880m, range: 336km

Quote
The LZ-4 is the engineer-produced and hand-built prototype of the LZ-5. Built specifically for research purposes, it was taken over by Curtiss Wright, where it was given the designation of CW-40. The LZ-4's maiden flight took place in November 1950.
P.Lambermont "Helicopters and Autogyros of the World", 1958
« Last Edit: May 24, 2016, 03:17:51 am by Skyblazer »

Offline mil

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Re: Doman helicopter projects
« Reply #24 on: February 12, 2018, 07:26:10 am »
Doman

Online hesham

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Re: Doman helicopter projects
« Reply #25 on: February 12, 2018, 03:26:12 pm »
Amazing find my dear Mil.