View Full Version : Early propeller I'm looking to ID

07-22-2016, 12:52 PM
Hey everybody,
I joined in hopes to get some information on a prop that I've waited 20 years to buy. I could not find a make on it and some of the information is not very legible. Obviously I'm not going to take any type of cleaning products to the finish of this prop to read the information. I hope somebody can help me out with the information I can provide. Any help as to what make it is and what aircraft it possibly went on would be greatly appreciated!

Overall length 104-1/4"
The center bore is smaller in the back at 3-1/8" diameter and 1-1/2" deep. It measures 4-1/8" diameter by 2" deep at the front and it looks to be hand chiseled. The back is not round but squared off, I'm thinking it locks into something or a second propeller maybe?
Bolt centers 8"
The prop itself reads:
The parts that are barely legible look like they read:
H9X 88
There's a set of numbers under the H9X but I cannot read them.
Please see attached photos. I can only upload one at a time so I will have to make a couple more posts.

Thanks again for any help!

07-22-2016, 12:55 PM
Back side of prop with squared center.

07-22-2016, 12:57 PM
Close up of some information.

07-22-2016, 01:03 PM
I have more pictures if needed.

07-22-2016, 04:14 PM
It's half of a 4 bladed combination most likely for a Liberty engine, hence the notching as you surmised. The "SE" prefix stands for "Steam Engineering", the Navy department that was responsible for procuring propellers for their flying boats during the late teens and early twenties. The "CP" prefix stands for "Curtiss Propeller" as was assigned to the company by the Navy, I believe, or possibly some other governmental agency.

The hub has been chiseled out, presumably for a clock or barometer.

A close up of the markings would be the most useful thing to have at this point. Sometimes they need to be deciphered if they are hard to read.

07-22-2016, 07:28 PM
Thank you for the info! I went out to the barn and took my flashlight to it for some pictures and I believe this is what the markings say:
88 X5H or 88 X5II
There is one other small marking I will attach as well.
Thanks again

07-22-2016, 07:30 PM
Small symbol under id.

07-22-2016, 09:29 PM
Small symbol under id.

That's "Curtiss Propeller", followed by a design number, followed by "Left Hand" ("LH"), which indicates the direction rotation to provide forward thrust. In this case it likely points to a pusher (rather than tractor) configuration.

I might be able to track down the CP number when I get home and can look through some reference materials. No promises . . .

07-22-2016, 11:28 PM
Thank you for the info you've given me so far. Is the SE364-380 a serial number?

07-23-2016, 07:30 AM
That's most likely a "drawing" number, referring to the blueprint from which it is manufactured. So it's really more like a model number.

Bob Gardner
07-23-2016, 01:33 PM

The angular shape of the propeller and the brass sheathing identify it as a design of the British propeller maker, Lang. He was lent by the Royal Navy to the USN at their request in 1917.

When the USA entered WW1, in 1917, the progress of aviation in America had been slow for a number of years. In Europe the catalyst of war in 1914, and the arms race which preceded it, had led to rapid developments in aviation.

Lang was loaned by the British Admiralty to bring the mass production of wooden propellers for the USN into being.

Propellers of your shape with the mortised hub were used with the Liberty engine in the Curtiss HS2L flying boat, which had a pusher engine, but they had different data stamped on the hub c.f yours. Please measure it from tip to tip and I might be able to confirm what it was used for.

The letters SE are for the Steam Engineering branch of the USN. Military aircraft were such an unusual novelty that several nations could not work out which branch of their respective service should have overall control of them! (Afternote: woops! I see that Dave had already mentioned this!)

I think you might like to have a copy of one of my books on British WW1 Aircraft Props, Part Three, which has sixty one pages about Dashwood Lang, the majority about Lang in Britain, and eighteen pages describing Lang's work in the USA for the USN; and 109 pages on two other British makers, which are not related in any way to the USA in general nor the USN. If this idea appeals tell me your email address via the personal message facility at top right of this page. I'll give you a discount on the price.

With kind regards,


07-28-2016, 09:12 AM
Hey Bob,
The overall length I measured from tip to tip is 104-1/4".
Thanks again for doing some research as to where it came from. I am also definitely interested in your book, I'll pm you my email address now.
Thanks again