Secret Projects Forum

Secret Projects => Postwar Aircraft Projects => Topic started by: boxkite on August 11, 2006, 01:53:57 pm

Title: Doman helicopter projects
Post by: boxkite on August 11, 2006, 01:53:57 pm
Is anybody familiar with the designs of Gliddon S Doman? This larger one was shown in "Der Flieger" magazine issue 9/1954 (page 206), but nothing about a D-... designation ...
Title: Re: Doman helicopter projects
Post by: snurg on July 24, 2007, 01:23:15 pm
Is anybody familiar with the designs of Gliddon S Doman? This larger one was shown in "Der Flieger" magazine issue 9/1954 (page 206), but nothing about a D-... designation ...

Only vaguely.  Glid Doman's company built about a dozen helicopters.  You probably can find information from the AHS website: http://www.vtol.org/ and the New England Air Museum: http://www.neam.org/articles/a_doman1.asp

Doman, temporarily, made Connecticut the undisputed center of the helicopter universe, with Sikorsky, Kaman (both still exists, and both still make new helicopters) and Doman.



Title: Re: Doman helicopter projects
Post by: Barrington Bond on March 18, 2008, 03:42:15 pm
The Aeroplane 2 November 1956.

Title: Re: Doman helicopter projects
Post by: Jemiba on June 06, 2008, 11:41:30 am
Another photo of the Doman Fleet ASW helicopter :
(from InterAVia Bulletin 1956)
Title: Re: Doman helicopter projects
Post by: dnellis on June 29, 2008, 06:32:37 pm
After receiving a layoff from Sikorsky Aircraft, I had the opportunity to work for Glidden Doman in 1959 - 1962.

He had originally worked as an engineer for Sikorsky Helicopter and had proposed a new transmission/rotorhead design which was not readily accepted by the engineering department of Sikorsky Aircraft. He had faith in the theory of his new design and soon left Sikorsky to find his own company. All of the dozen or so of us working at Doman Helicopters had faith in the design which was remarkable. Most helicopters of the time had a massive gear reduction at the reciprocating engine and power was transmitted to the transmission/rotorhead as low speed/high torque via a hollow shaft of 5 to 6 inches in diameter.

The Doman design had engine gearing that sped up the output RPM to transmit power via a solid shaft of about 1 and a half inches diameter at a high revolution. The force being transmitted was low torque/high speed.   

The rotorhead transmission was completely enclosed. All mechanical linkages were housed within the transmission body which gave the appearance of having the rotor blades project from the large transmission "can" which sat above the fuselage. The efficiency of the design allowed the Doman helicopter to carry a much higher payload and it was much more efficient at altitude. It was the only helicopter of the period which had the ability to cross the Andes Mountains carrying a payload. Many of the records then set remain unbroken.

Test pilots reported the absence of high vibration and ease of control. Due to it's stability, the craft could be flown without having a death grip on both yoke and cyclic sticks.

War is the father of all great developments, and if Doman could have survived into the Vietnam War era we would see the Doman design as the standard of today's helicopter.

The system was patented and information may be attained through the U. S. Patent Office. As these patents have now expired it may be time for someone to resurrect the design.
Title: Re: Doman helicopter projects
Post by: dnellis on June 29, 2008, 07:13:24 pm
Some web URLs about Doman.

http://www.neam.org/articles/a_doman1.asp
http://www.aviastar.org/helicopters_eng/doman.html
Title: Re: Doman helicopter projects
Post by: Barrington Bond on June 30, 2008, 11:02:35 am
Very enlightening thank you for posting that :)

Regards,
Barry
Title: Re: Doman helicopter projects
Post by: Hood on July 24, 2011, 09:06:20 am
I wonder if Boxkite's first post shows the Berlin-Doman BD-19?
It seems that this new firm was created after the demise of Doman Helicopters Inc. maybe around the same time as the Puerto Rico based Caribe Doman company was formed. I know nothing about the BD-19 other than the designation.
Title: Re: Doman helicopter projects
Post by: Skyblazer on December 15, 2011, 07:47:30 pm
I wonder if Boxkite's first post shows the Berlin-Doman BD-19?
It seems that this new firm was created after the demise of Doman Helicopters Inc. maybe around the same time as the Puerto Rico based Caribe Doman company was formed. I know nothing about the BD-19 other than the designation.

No it's not. I do not have a picture of the BD-19 but I know it was to be an 8-seat transport helicopter powered by two Allison turbines.

The only Doman project of that size that I know of was the HC-3, "transportable bodily by a Fairchild C-120 Packet and designed to carry a 6,600-lb load for no miles, or 1,300 lb for 1,400 miles. As a flying crane it could lift a 12,000-lb object for a short distance; troop capacity would be 33." I don't know if this is the HC-3, though.
Title: Re: Doman helicopter projects
Post by: hesham on December 16, 2011, 06:36:55 am
Hi,


I think it was Berlin-Doman BD-19.


For the HC-3,please see;


http://www.secretprojects.co.uk/forum/index.php/topic,3107.msg25096.html#msg25096 (http://www.secretprojects.co.uk/forum/index.php/topic,3107.msg25096.html#msg25096)
Title: Re: Doman helicopter projects
Post by: Skyblazer on December 16, 2011, 06:51:06 am
Thanks a lot for the BD-19 photograph... but it can't be the same as the one in the first pic. Check the length of it, the number of windows, the shape of the fuselage...
Title: Re: Doman helicopter projects
Post by: Platt-LePage Aircraft on December 17, 2011, 01:41:22 pm
No one thought about asking Glidden Doman, or the New England Air Museum?

http://windmillengineeringbygammaventures.com/aboutus.aspx

http://www.neam.org/ (http://www.neam.org/)


http://theepcogroup.web.officelive.com/DomanHelicopters.aspx

Title: Re: Doman helicopter projects
Post by: Skyblazer on December 17, 2011, 01:46:32 pm
Gosh! Thanks for the pointer. I didn't even suspect Glidden Doman was still alive!
Title: Re: Doman helicopter projects
Post by: Platt-LePage Aircraft on December 17, 2011, 06:56:59 pm
He may be the last of the original helicopter pioneers left.

My last PL-LP contact passed away in 2009.
Title: Re: Doman helicopter projects
Post by: Skyblazer on May 14, 2013, 04:59:32 pm
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...
Title: Re: Doman helicopter projects
Post by: hesham 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.
Title: Re: Doman helicopter projects
Post by: Mark Nankivil on April 20, 2015, 06:40:54 am
Hi All -

Looks like a Dolman design to me:


http://www.ebay.com/itm/21345-Photo-Lot-2-Early-Vintage-Test-Experimental-Helicopters-Aviation-Plane-/251449131447?pt=LH_DefaultDomain_0&hash=item3a8b8941b7

Enjoy the Day!  Mark
Title: Re: Doman helicopter projects
Post by: hesham on January 06, 2016, 08:25:33 am
Hi,

http://archive.aviationweek.com/search?QueryTerm=doman+project&DocType=Article&sort=
Title: Re: Doman helicopter projects
Post by: hesham 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

Title: Re: Doman helicopter projects
Post by: hesham on April 23, 2016, 08:42:47 am
Hi,

does any one hear about Doman BD-68 design ?.
Title: Re: Doman helicopter projects
Post by: Apophenia 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.
Title: Re: Doman helicopter projects
Post by: hesham on April 25, 2016, 04:40:18 am
Many thanks to you my dear Apophenia.
Title: Re: Doman helicopter projects
Post by: Skyblazer 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:
Title: Re: Doman helicopter projects
Post by: Skyblazer on May 24, 2016, 03:15:33 am
(https://www.secretprojects.co.uk/forum/proxy.php?request=http%3A%2F%2Fwww.secretprojects.co.uk%2Fforum%2Findex.php%3Faction%3Ddlattach%3Btopic%3D572.0%3Battach%3D525983%3Bimage&hash=4ceead79085bceca84e9706692d5b3cb)  (https://www.secretprojects.co.uk/forum/proxy.php?request=http%3A%2F%2Fwww.secretprojects.co.uk%2Fforum%2Findex.php%3Faction%3Ddlattach%3Btopic%3D572.0%3Battach%3D525985%3Bimage&hash=703bc5d2ef0845ef3b1da23613cb4422)

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
Title: Re: Doman helicopter projects
Post by: mil on February 12, 2018, 07:26:10 am
Doman
Title: Re: Doman helicopter projects
Post by: hesham on February 12, 2018, 03:26:12 pm
Amazing find my dear Mil.
Title: Re: Doman helicopter projects
Post by: hesham on September 14, 2018, 06:31:50 am
Is anybody familiar with the designs of Gliddon S Doman? This larger one was shown in "Der Flieger" magazine issue 9/1954 (page 206), but nothing about a D-... designation ...

Hi,

here is a three Projects to Doman,one displayed by my dear Boxkite before as an ASW
Helicopter Project for Canada,second was Fuel Tank Helicopter (FHT) for USAF and the
third was an All-Weather Instrumentation Helicopter.

http://archive.aviationweek.com/search?exactphrase=true&QueryTerm=+project+helicopter&start=80&rows=20&DocType=Image&Sort=&SortOrder=&startdate=1916-08-01&enddate=2001-01-29&LastViewIssueKey=&LastViewPage=
Title: Re: Doman helicopter projects
Post by: RAP on November 25, 2018, 07:58:16 am
Another picture of the Doman ASW helicopter.