The Alula wing design and its applications

[hesham]

Hi,

we know this company aircraft,DH.6 and Semquaver actually built light aircraft
and here is anther project based on its wing.

http://www.flightglobal.com/pdfarchive/view/1920/1920%20-%200860.html
http://www.flightglobal.com/pdfarchive/view/1920/1920%20-%200814.html

 

[hesham]

Hi,


here is anther drawing and picture to Alula from L'Aerophile 8/1920.

 

[Stargazer2006]

Clearly identified as a Blackburn design in the last picture's caption.

 

[Jemiba]

Indeed, there wasn't a British company with that name, the two Flight articles already are
clearly indicating, that "Alula" was the name given to that wing design and Blackburn started
to draw some designs utilising it.
As we still had no general topic for Blackburn, I renamed this one.

And at the risk of being the man with the moustache and rasping voice again, please, please
folks, read your sources carefully ! If you have doubts, because having problems understanding
the particular language, just ask a native-language forum member !
Please try to keep the quality of this forum on a high level !

 

[Jemiba]

I would rather like to let the Sidney/Nile thread on its own, as we already have quite a lot of material
about those types and generally more specific threads are better to handle, both for the mods/admins
and for the members. Such general threads are good for types or concepts, that actually didn't got a
designation, or for those, we have very few information about. And if we have a handful of posts with,
say, "Unknown Blackburn Type", we just can merge them in a single thread.

 

[hesham]

By the way,


I called Alula as the book,British Civil Aircraft since 1919,volume one.

 

[Stargazer2006]

"Alula" was just the name of the wing design. "Alula D.H.6" was an Airco D.H.6 fuselage mated with an Alula-type wing.

 

[lark]

Correct ! The name Alula refers to some features on a bird wing....
Not a company as Jemiba and Star..stated.

 

[hesham]

Correct ! The name Alula refers to some features on a bird wing....
Not a company as Jemiba and Star..stated.

That's right my dear Lark.

 

[Stargazer2006]

Correct ! The name Alula refers to some features on a bird wing....
Not a company as Jemiba and Star..stated.

Wrong. I am the one who said it was NOT a company name!

 

[Jemiba]

... and the caption in "British Civil Aircraft since 1919" clearly says "... Conversion by
the Blackburn Aeroplane and Motor Co.Ltd.".
That's what I meant with "reading sources carefully" .

 

[Stargazer2006]

Name of topic changed.

Here's yet another hypothetical Alula wing design (seemingly related to Handley Page, whom the article claims fathered the concept), "The Pelican Four-Ton Lorry", a proposed colossal cargo cantilever monoplane capable of carrying four tons (Scientific American, October 1929):

 

[Schneiderman]

Reading the various articles shows that the ‘Alula’ wing was conceived by A.Holle and marketed in the UK by The Commercial Aeroplane Wing Syndicate. I did a quick search but could not find any patents in the name of Holle but the ‘Pelican’ cargo carrier is shown in a 1920 patent held in the name of the Syndicate and Harris Booth (GB167068A). Booth was a designer who worked for the Air Department of the Admiralty in the war and then moved to Blackburn, hence the link to that company. I cannot find any note as to who the Syndicate members were or why Booth became associated with them.

The reference to Handley-Page in the Scientific American article concerns their slotted wings and not the ‘Alula’, so the aircraft design will be Booth again although probably not Blackburn as he had left in 1924

 

[Stargazer2006]

Thanks a lot Schneiderman for clarifying this.

 

[hesham]

Great find my dears.

 

[Retrofit]

From "The Speed Seekers" (Thomas G. Foxworth, 1975), details of the modification of the Martinsyde Semiquaver biplane racer (Aerial Derby 1920) into the monoplane with Alula wing.

 

[Schneiderman]

"The Pelican Four-Ton Lorry", a proposed colossal cargo cantilever monoplane capable of carrying four tons (Scientific American, October 1929):

Is this really from October 1929? I ask because the article in Aeroplane mentioning the 4-ton lorry was published in July 1920 and described in detail in Aug 1920

 

[Stargazer2006]

this really from October 1929? I ask because the article in Aeroplane mentioning the 4-ton lorry was published in July 1920 and described in detail in Aug 1920

Well I must admit it does seem strange to me as well... Unfortunately I do not have the original magazine, this was shared by one of my online contacts, and that's the date he gave for it...

 

[Schneiderman]

Well Booth's design was definitely from 1920, in his Blackburn days, as in Hesham's first post. Sorry about the quality of the image.

 

[Stargazer2006]

Well Booth's design was definitely from 1920, in his Blackburn days, as in Hesham's first post. Sorry about the quality of the image.

No problem! This is a great resource, and it can easily be enhanced. See?

 

[Schneiderman]

I've used the traditional English spelling "tonne" here instead of "ton".)

Well, as a Brit who goes back way before the metric era it's not a tradition that I was aware of Ton is correct, tonne is 'Olde English' of Shakespeare's era.

The image was a quick screen grab, I'll see if I can replace it with a better version

 

[Stargazer2006]

Well, as a Brit who goes back way before the metric era it's not a tradition that I was aware of Ton is correct, tonne is 'Olde English' of Shakespeare's era.

I thought it was still in use during the 1920s, hence my use of it in the image.
I'll edit it to reflect your correction, thanks!

 

[Justo Miranda]

From

 

[hesham]

Very Cool,thank you my dear Justo.

 

[Schneiderman]

The problems with the theory behind the alula wing are well covered in the attachments to various posts above so I thought I would add a bit of background regarding Holle. This is what I have found.

Alexander Albert Holle, Dutch and originally a tea planter, held many patents. The earliest appears to be UK Patent 12869 for Improvements in Steam and other Fluid Pressure Engines held in association with the S.M. Car Syndicate. He became a resident in Britain sometime prior to WW1
Holle established the Varioplane Co. Ltd in September 1913 to acquire the rights to his patents. Capital was £16000 in £500 shares, directors Holle, G.J.L.Nicholson and G.P.M Van Weel. The Syndicate also held patents in association with others applied for during the war years.
The patent for what became known as the alula wing, named after the small feathers on the leading edge of some birds wings, was applied for in 1918. The aim was to manage the flow of air over the wing’s surface through the application of wash-out and taper and to eliminate the need for drag-inducing ailerons by altering the air-flow and lift over the wing by the use of auxiliary aerofoils on the leading edge.
In 1919 a new company was formed to build and test an alula wing and exploit the potential. This was the Commercial Aircraft Wing Syndicate Ltd, with capital of £30000 in £1 shares. It was a co-venture between Holle, The Varioplane Co Ltd and Blackburn Aeroplane and Motor Co Ltd. Where Varioplane could appoint three directors and Blackburn two, which probably gives an indication of the split in funding.
A revised patent for the alula wing was then granted in 1921; this featured a more refined version of the auxiliary aerofoil. I would think that Handley-Page’s lawyers would have had a close look at this patent as it is very similar to their slot system in some aspects.
The story of the test flights of the alula wing and the projects proposed by Booth have been covered in this thread already.
Holle seems to have lost interest all in aircraft after 1921 as all his later patents refer to road vehicles.

 

[Stargazer2006]

Thanks a lot for you highly valuable contributions to this topic, Justo Miranda and especially Schneiderman.

 

[steelpillow]

According to H. A. Taylor; "Fairey Aircraft since 1915", Putnam, 1974, p.63, Penrose gives some information about the Varioplane Co. in his "British Aviation: The Great War and Armistice", Putnam. Taylor suggests that (presumably Holle) had been experimenting with flexible wings for some time.
Has anybody got a copy of Penrose?

[Update]
Holle and a colleague called Judge patented a variable-camber aerofoil mechanism in 1916, while with the Varioplane Co. Some drawings are reproduced in L.F. Campanile; "Lightweight Shape-Adaptable Airfoils: A New Challenge for an Old Dream", Adaptive Structures: Engineering Applications (Ed. David Wagg, Ian Bond, Paul Weaver, Michael Friswell), Wiley, 2007, pp.89-129. Check it out on Google Books.

 

[riggerrob]

Alula plan form reminds me of the Schumann wing plan form employed by the highest performance sailplanes and airliners. The designer's name is Wil Schuemann, though some writers use the simplified spelling of "Schumann." It has a straight trailing edge with a double-tapered leading edge than blends into an elliptical curve near the tip. Schliemann was trying to solve a tip-stall problem - on the predecessor to the Discus sailplane - by encouraging a bit of span-wise (towards wing tips) flow to delay that annoying tip-stall.
Modern airliners have Schuemann-ish curved wing tips to reduce the size (and drag) of wing tip vortexes.

Amusing that Alula has leading edge control surfaces. Many have experimented controls, but none reached production.