Boulton Paul Lift Fan Designs


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26 May 2006
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the Boulton Paul P.135 was VTOL reserach aircraft project and
had a single lift-fan.


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From The Aeroplane some nice schematics of a Boulton Paul lift fan.


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A possible application was the P.132 Research aircraft, a design from 1956:
(from Alec Brew "Boulton Paul Aircraft")


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Refferring to the mentioned book, the P.132 was intended to uselift fans only.
Do you thought of the object, looking like a jet pipe, as part of jet deflection ?


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Well at first glance I thought that there was jet deflection there. Studying it a bit more it does seem that it is a contraption that is powering the lift fans (as pipes/shafts go off to the wing and fuselage units) from a large pipe coming off of the engines.

I did some searches and didn't find anything mentioned about the machine. So I thought I'd make a new post, if that is okay.

I was talking with a friend the other day, about aircraft design as you do, talking about why aircraft tend to have dorsal rather than ventral tail fins. I was reminded of this Boulton Paul design that had ventral fins only, and wheels on the end of them. Should surely save weight, not needing a main set of undercarriage legs.

So what information can you share on this machine? thanks. ^_^
This was a group of proposals formulated in late 1954/early 1955, and designated Mk 1 to Mk 12, for VTOL aircraft having fanlift. Details of only two of them survive. The Mk 6 was a fairly conventional delta-wing aircraft with a centrally-mounted 54 in diameter contra-rotating fan, and powered by five Rolls-Royce RB.108 engines. The Mk 8 was a more radical delta powered by two Bristol Orpheus engines, and featuring a 75 in diameter contra-rotating fan, with three smaller balancing fans in the wings and the nose. The twin fins were underslung and supported the mainwheels of the tricycle undercarriage. This layout was to give adequate ground clearance for the large mass airflow from the fans. The Mk 8 design had folding wings and a cannon mounted in each wing inboard of the balancing fan, and outboard of an underwing pylon.

Alec Brew, Boulton-Paul Aircraft since 1915, Putnam 1993


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"Should surely save weight, not needing a main set of undercarriage legs."

this is a concept, that was favoured by the good old Luigi Colani, too, who used it
in quite a number of designs. I don't know any more, where I read about it, but once
there was a report about the credibility of his designs, especially mentioning the concept
of the "symbiosis of fin and main gear", as he called it, too. And IIRC, the result was quite
disappointing : The fins of course would have to be beefed up considerably and in
most cases would have a shape, which would be less than ideal aerodynamically. And
the landing gear itself would be heavier, than necessary, because of the not ideal
load distribution.
Thats the one, thanks for the replies.

I guess if there was any advantage to using fins as landing gear it would be more commonly seen. Being a VTOL design it was a possible option on the P.130 then.

Maybe such a langing gear arrangement would make better sence with an ultralight than a military fighter. not quite the same but a Quickie comes to mind with the main gear on the ends of the canards.
From Aviation Week, Septemner 1960:


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Alec Brew's Boulton Paul Aircraft (Budding Books 1998 Edition) has a rendering of the P.135B high-speed experimental version. It was to be used in the investigation of fan-lift combat applications.


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Wow,incredible design my dear Cy-27;

thank you for sharing.
See attached image of the A.S. Viper powered P.132 from Alec Brews Boulton Paul Aircraft (Budding Books, 1998 edition) ISBN 1840150785


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Thank you so much for posting, it looks like the P.135B is the missing link between the P.132-5 and the P.136. The P.136 as illustrated in Kites, Birds & Stuff - Boulton Paul Aircraft by P.D Stemp looks almost identical to the P.135B except is uses 6 x RB.108s mounted in the centre fuselage instead of the Boulton Paul lift-fan system of the P.135B. Based on that the P.135B was probably designed for a pair of Bristol Siddeley Orpheus engines too. Is it possible that the P.135 and P.136 were aimed at the same ER.161T that the Armstrong Whitworth AW.171 was designed to?

P.130 Mk.8 Fan diameter is 75-inch and P.130 Mk.6 Fan diameter is 54-inch. Mk.8 is said for the Navy.
But I can't see any fan in this drawing. ???


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So I can see fan drive turbine located under the engines which connected to three fans by shaft ? This fan is not gas drive type?
Also I can see jet deflector under the fans in this drawing.;topic=3668.0;attach=44159;image


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From Aviation magazine 1961.


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