Dashwood Lang was the owner of the British Lang Propeller Co. When the USA eventually entered WW1 in 1917, the USN asked HMG in September 1917 to send an expert to advise on propeller design and the massed production of props. They sent Lang. He formed the Lang Propeller Company of America and introduced a separate nomenclature for US prop drawing numbers.
Your prop carries British prop data and was probably made in Britain and shipped to the States where Lang applied his American decal.
So, your prop must date from the first few weeks of Lang's time in America; perhaps October to December 1917. It is probably the only example likely to survive. The prop was made for the SE5A aircraft designed by the Royal Aircraft Factory in England and carries their drawing number T 28137. The diameter is shown as 2.514m.
Firstly, congratulations on owning such a wonderful prop. It represents a major evolution in American naval aviation.
The data you seek is available here, within the Wooden Propeller forum. Dave Bahnson, who created this forum, has published many British and American databases. The one you want will be entitled something like British WW1 Propeller Data which lists all British drawing numbers from c1912 to 1920. They are listed in alphabetical order. They are alpha-numeric where the initial letter, or sometimes letters, indicate the design authority for the prop, which is sometimes also the manufacturer. The list begins with the letter A for (surprisingly) the Vickers Company. Your drawing number begins with the letter T which indicates the British Government's Royal Aircraft Factory.
There are often several, sometimes many, slight variations. There are five variations for T28137. I have just added to my master copy a sixth for your prop where the variation is that the diameter is 2514mm whereas the design specifies a diameter of 2515mm. A slight variation was allowed for manufacturing difficulties.
And I have also added to my master copy a note to describe your (probably) unique example.
I wrote to Dave and he didnt have any British WW1 Propeller Data listed. Could you possible send me some scans to planepieces@gmail.com with info regarding model number: T28137. Much appreciated. Happy Holidays! -RT
RT, it's not that I don't have lists. It's the fact that they are copyrighted and I don't have permission to publish them on this site.
However, I doubt that I'll get in any trouble for attaching an image which comes from the Windsock Data File collection titled WW1 British Aeroplane Propellers.
Some of that data has been listed in other publications, but the attached clip may be what Bob is referring to in his research.
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