old 4 blade propeller

[thegoodolddaysltd]

can anyone help, approx 6 years ago i purchased an old 4 blade wooden propeller which has sat in my shed until now i did not realise until now that it had writing on it it has 8 bolt holes with a 2 1/2'' opening in the middle reducing to 1 1/4" on one side and 2 1/8" reducing to 1 1/8" on the other and have just noticed that it has words and numbers running around it which say;
90 HP Curtiss D 2438 Curtiss AD 503 LP 12166 WD 20.4.17 and a little box with some initials in but this is faint AID 47U or something like that
Regards George

[Bob Gardner]

George,

Your prop was made in April 1917 for a Royal Navy training aicraft, the Curtiss JN3, powered by the 90hp Curtiss engine. The diameter was 2438mm. The prop was probably made by the Lang Propeller Co whose serial no. was LP12166.

AID47U is the airworthiness stamp od the Aeroplane Inspection Department,

With kind regards,

Bob

[thegoodolddaysltd]

curtiss 90 hp propeller

Thanks for the info
Kind Regards George

[thegoodolddaysltd]

curtiss 4 blade prop

Having trouble finding jn3 with 4 blades have been pointed in the direction of a Handley page twin engine bomber of 1917 which on close inspection the profile/shape looks very similar or the same can you show me any pictures of a jn3 with 4 blades
Regards George

[pmdec]

Hi,

It is definetely IMPOSSIBLE to find the destination of a propeller by its shape: there are thousand of them...
The only way is by the markings.
Looking at them and write what you saw is an option, but far from the better one, because without some practice misreadings are easy. Posting clear pictures of the markings is the more reliable for people like Bob, Dave and some others to give a documented answer.

Regards,
PM

[Bob Gardner]

George,

I am sorry if I have misled you. The relevant data on your prop is definitive. We are not giving you our opinion or our guess.

It translates as;

AD 503 The drawing number if the Air Department of the RN.
D 2438 The diameter of the prop in mm (the distance from tip to tip across the hub.
Curtiss 90hp; The American engine purchased by the RN.

The drg number AD503 with the Curtiss OX engine was only used on the Curtiss JN3. The prop was also used on the SSP airship, but with a Rolls Royce 70hp engine. AD503 was the standard prop for the Navy JN3 from 1917 to 1919.

The HP O/100 and O/400 bomber used by the Royal Navy does have four bladed props that have a resemblence to yours; they were both designed by the Air Department of the Admiralty. But whereas your prop has a dimater of 2.438 metres (8 feet) the HP bomber had props of 3.350 metres (11 feet).

With kind regards,

Bob