Help with identification of Sopwith? propeller

[suewalkerdine]

We have an old unrestored propeller which we believe came from a plane my husband's grandfather flew in the first world war. He was an ace and flew SE9's in the 56th squadron.
The propeller is marked
AB7840LH
220 HP RENAULT
D3170 P120
ADP and
G462 N47
Apart from finding out it was a Sopwith we're no further on.
Thanks for any help.

[Bob Gardner]

Good Evening Sue,

Welcome to the forum.

Your prop is from an airship operated in WW1 by the Royal Navy, known as the Coastal Airship. Your prop is from the aft engine.

Your data translates as;

AB7840LH A prop designed by the Air Board (possibly inherited from the RN) in late 1917 or 1918, the prop designed for left hand rotation.

220 HP RENAULT The engine

D3170 Diameter 3170mm

P120x Pitch, probably 1200mm

ADP Inspected and passed by the Air Department of the Admiralty

G462 N47 The batch number (of 100 props, of which number 47), the contract placed in late 1917 or early 1918.

With kind regards,

Bob

[suewalkerdine]

Thank you very much Bob.
That is not at all what we were expecting! I had realised its diameter was quite large, now I know why!
Does it have a value at all and if not can we restore it?
(I have read the notes on restoration).
Thanks again
Sue

[Bob Gardner]

Good Morning Sue,

I was aware that my description of your prop would be a suprise and I hope the news has not caused too much consternation!

Can you post some photographs of the prop here? There's a tutorial that explains how to do it.

The best thing for the prop is to polish it with pure beeswax. This must be pure beeswax out of a tin, not the aerosol variety sold by Sainsbury's et al which have silicones that can cause old lacquer to bloom.

If it hasn't been polished for yonks, polish it front and back once a month for a few months.

It is always best to keep a prop unrestored for as long as possible to preserve the originality. But these WW1 props are now around 100 years old; the wood is drying out; the glue is crystallising and beginning to force the laminations apart. We conserve most of the props that we sell, which means we halt the deterioration. Some we lightly restore.

Airship props and big props don't command as much interest as props from famous aircraft such as the SE5 and Sopwith Camel. If offered at auction in the UK, I think it would sell for £1000-£1200 GBP. It's insurance value (the cost of a suitable replacement from a dealer) is about £2000 GBP (about 3200 USD). But this is the first Coastal Airship prop I have heard of in the last fifteen years, so, if lost, you would not be able to find an exact replacement.

With kind regards,

Bob

[suewalkerdine]

Thanks again Bob!
Photo attached below

[Bob Gardner]

Big, isn't it !!!

Bob