Kuckir VTOL Project 1918-1919


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20 June 2006
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For those that thought the Focke-Wulf Triebflugel was an original design I found Kucfir’s VTOL project of 1918-1919.

Konrad Kucfir a Polish inventor applied for a patent on 14 April 1919 for his tail-sitter. Basically a single/two-seat biplane standing vertically on a large tripod frame structure embracing a normal monoplane tail unit. Instead of a normal aircrew, the aircraft had another set of biplane wings with planes shaped like propeller blades which, mounted horizontally above the standing aircraft, rotating around its vertical axis. Providing vertical life for take-off and hover and propulsion in normal flight.

The propeller wings were attached to a central drum structure which carried two radial engines mounted back to back, and two airscrews, one in front of the leading edge of each set of propeller planes, were driven by chain or rope gearings from the engines.

The propeller wings and normal wings were fitted with ailerons, and transition form vertical to horizontal flight was to be effected by the elevator movement.

The tripod landing frame over the tail was to be equipped with shock-absorbers.

The patent also envisaged a number of variations of the design, including a monoplane propeller wing and one or more engines.

Poland granted patent number 1707 on 4 March 1925.

My scanner is still packed so I will post a drawing once that gets hooked up. There is no other data available.
I found the pieces over the weekend and just got it set up (I hate moving).

Diagram to follow, thanks for the follow up.
From "Polish aircraft, 1893-1939", by Jerzy B. Cynk

Putnam 1971


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That's great fun! I am glad he didn't try to actually build one, though. I imagine the gyroscopic forces would have been pretty terrifying. It would have been a start, though...maybe we would have seen a piston engine antecedent to the Convair Pogo come along before WWII. Thanks for sharing.

PS--You seem to have posted your attachments twice.
Truly excellent and informative postings, Justo (as ever).
What a wonderful machine - sort of Jules Verne Triebflugfel.
I find Kucfir's patent is online at:
The patent contains a nice plan view plus some details of the propellor arrangements. (Alas, I have no scanner.)
All best, 'Wingknut'
Re: Kucfir VTOL Project 1918-1919

Oh dear - the document is still there at the above-listed URL. I'll try attaching it to this message, Maveric. (It's not a very big PDF.)
Failing that, a swift Google of "Konrad Kucfir" should take you right to it.
Cheers, 'Wingknut'.


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Re: Kuckfir VTOL Project 1918-1919

Just returning to one of my all-time favourite unbuilt aircraft:
Slightly larger blow-up of the image that Justo posted above, source: http://www.samolotypolskie.pl/samoloty/1558/126/Kucfir-wirolot
Colour two-view, source: https://dl.dropboxusercontent.com/s/0u6izqeblwr9ecx/kucfir_wirolot_pol.png
EDITS: plus an image from the original patent above.

Not having seen 'wirolot' before, I checked it out. Google Translate won't seem to translate the word 'wirolot' itself but suggests 'wir' and 'wiro' translate from Polish to English as 'vortex' and 'eddy' respectively, while 'lot' translates as 'flight'. (Cf. 'samolot' = 'aircraft', I think). So I wondered if 'wirolot' means (e.g.) "vortex-plane" or "vortex-flier"?
As far as I can tell, Polish web-sites tend to reserve "wirolot" for convertiplanes or compound helicopters, e.g.
As opposed to 'śmigłowiec', which I think translates as "helicopter".


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