Denny's helicopter

robinbird

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Researching helicopters during WW11 I came across the Denny built helicopters prior to WW1. The Dumbarton factory, which built aircraft in WW2, pioneered the Denny Mumford helicopter between 1906-1914. Its last test flight reached an altitude of 10 feet for around 100 yards. While beached for the night it was wrecked in a storm. The following month WW1 was declared, killing off this pioneering project. Was this the first helicopter to use an engine and transmission?
 
I recall seeing a nice display model of the Denny helicopter on display at the Denny wave tank museum in Dumbarton
I'll take some pics upon my next visit over
 
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A brief description from: Cameron, D. and Thomson, D.G. (2008) Scottish contributions to rotary wing flight. In: AHS 64th Annual Forum, April 29th - May 1st, 2008, Montreal, Canada.

"Denny/Mumford Helicopter 1905 - 1914

In early 1905, Edwin Mumford, head of the Experimental Tank at the Denny shipyard constructed a prototype Helicopter... As the main business of Denny’s was of course shipbuilding, experiments on the helicopter were of low priority, and development was an extended process. The ship building heritage of the machine is also evident from the design of the “rotors” which more resemble ship screws than rotary wings. Initial experiments used one “lifting screw”, but the final version of the vehicle had six. Each screw was 24ft in diameter and was constructed of fabric stretched over a wooden rim, wiring bracing being used to provide structural stiffness. It was calculated that the screws would have to be rotated at 45rpm to generate sufficient lift for flight. The design was very much governed by the lack of availability of a light weight powerplant. In the end a single 4 cylinder, 2-stroke engine providing 40 h.p. was sufficient to lift the 1600lb vehicle. Tethered flights were eventually successfully made, versions mounted on skis and floats built. Development of this vehicle ceased in 1914 due to the onset of WW1, and the much more spectacular successes of fixed wing pioneers such as the Wright Brothers."

That leaves unanswered when exactly the Denny-Mumford helicopter first flew.

The Scottish Maritime Museum says "maiden flight in 1908" but also says that "it rose in the air under its own power on 7th September 1912". But I can't puzzle through how the Denny-Mumford had 1908 'maiden flight' without being "under its own power"

 
Thanks for the feedback. Early helicopter and rotary flight interest me because dad filmed early trials during WW2. The wave tank museum at Dumbarton was always closed when I visited Helensburgh because dad was with the Marine Aircraft Experimental Establishment. MAEE worked closely with Denny and Blackburn using its testing tank before getting its own facilities. Incidentally, when the Blackburn B20 crashed it was about to be handed over to MAEE for its air worthy certificate.
After Helensburgh dad, Bob Bird, transferred to the AFEE Sherburn and Beaulieu, where he photographed the Focke Achgelis Fa233 and the first captured Fa330 as flown by Robert Kronfeld. The once top secret pictures are now in the public domain and National Archives
 
But I can't puzzle through how the Denny-Mumford had 1908 'maiden flight' without being "under its own power"

Some sources refer to early tests being carried out using an electric motor, with the helicopter being tethered, which would explain things.

In addition to the Cameron and Thompson paper, there is also this paper:

"Glasgow - Helicopter Birthplace" by Elfan ap Rees​
"Proceedings of the 16th European Rotorcraft Forum"
Glasgow, September 18 - 20, 1990​

Unfortunately, I don't have a copy of it. Any chance that another forum member does, though?

Attached are a couple of photos, found online, of the model that's at the Scottish Maritime Museum @ Irvine, plus three contemporary photos.

Cheers,
Paul
 

Attachments

  • Mumford Denny model 1.jpg
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  • Mumford Denny model 2.jpg
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  • Mumford Denny close-up.jpg
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  • Mumford Denny rear view.jpg
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  • Mumford Denny side view.jpg
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A number of patents had also been taken out. These are well worth viewing, due to the 3-view drawings contained in each.
 

Attachments

  • GB190503214A.pdf
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  • GB190515698A.pdf
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  • US892380.pdf
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