Please Help Identify My Lang 3507A Propeller

[jojoc@erols.com]

Greetings All,

My very first posting and apologies if any etiquette violations. Thank you in advance for your interest.

My name is George and I can not find any information about the wooden propeller I have. I am hoping you can help, please.

Markings: Liberty Motor Lang Propeller No 3507A Pitch 1.800 Dia 2.642 DR NO LP 401E LH 400 HP
Material: Wood (dark)
Condition: Original
Length: 104 inches
Pics attached.

About 40 years ago I received this from a neighbor who said it was from a plane he flew. I was siz years old. That is all I know.

Thank you again.

George
jojoc@erols.com.

[Bob Gardner]

Welcome George!

We don't have etiquette. We just talk to each other and try to help people identify their props.

There is very little public knowledge about early propellers. What there is resides in museums, who are not always willing to share it, and amongst a few of us who are trying to gather information. The creation of this forum by Dave Bahnson has helped enormously.

Not much is known about Lang Props of America other than it was a British firm brought over to America by the British Admiralty to assist the USN expand in 1917 when the US entered WW1. Hence, all Lang of America props were very probably made for the USN and the metal sheathing on your prop confirms that it was made for a seaplane.

The diameter of 2642mm and the pitch of only 1800mm suggest that it was made for something large and slow. 400hp most probably indicates that it was made for the Liberty V12 engine. The prop serial number of 3507 indicates that it is some way down the production line and probably dates from mid 1918.

The thin depth of the hub suggests that this prop is half of a four bladed prop. They were made in two halves so that spare props could be easily stored on board ship.

There have been several other threads on US Lang props in this forum which you might wish to read using the search facility.

With kind regards,

Bob

[Bob Gardner]

Postscript.

The USN had four flying boats in service in 1918 that used the Liberty V12 engine, NC 1, F5 L, H16, HS2 L.

Bob

[Dave]

George, also note that your propeller appears to be notched in the hub, and is about half the thickness of a normal Liberty engine prop. That's because it's half of a 4-blade combination. They interlocked when mounted on the hub.

I agree that it was almost certainly used for one of the Navy flying boats in the late teens and early twenties. You should see some stampings around the hub that consist of "USN" and a ship's anchor overlying it. The fact that it's a left handed rotation ("LH") and used on a Liberty engine would make it a pusher configuration. I have seen the LP401 number in the past, as it seems to be a common one, but haven't been able to narrow it down to a single aircraft type.

The Navy had thousands of these propellers in their inventory in the early twenties. They quickly became obsolete with development of better engines (and propellers) so they were sold off as surplus for $2 or $3 each.

[jojoc@erols.com]

Thank you for the feedback.

Bob, Dave,

Wow! I love the history and thank you for the information.

I am considering selling it because it has done nothing except lay in my garage for 30 years. Perhaps I will find someone who will appreciate it more than me.

Thank you again.

Joe