AID inspection stamps

[StevieB]

Hello All,

I have a wooden Martinsyde G100 propeller that has a couple of AID inspection stamps:

AID 762 & AID 88A (the letters above the numbers in small boxes), and an A above an /|\ (which I take to be the Air department WD acceptance stamp.

Does the 762 & 88A actually mean something relevant or traceable?

Thanks in advance

Steve

[Dave]

My general understanding is that each number corresponds to a specific inspector, so some information can be inferred by comparing stamps. Bob Gardner has been researching those and I honestly don't know what the status of that is at the moment.

[StevieB]

Thanks Dave,

This isn't my usual collecting field, and whilst working out what to do with it I thought it would be interesting to find out as much about it as possible. Other markings (and what I think they refer to) are:

"Avro Y120 120 HP Beardmore Daimler Martinsyde Biplane", stamped into the front of the boss. The 120HP indicates the earlier G100, I think.

"R3" stamped underneath the above - no idea what this is.

"2896" - Diameter?
"1840" - Pitch?

on the underside of the boss.

On the top of the boss is "69?3" - the 3rd number unreadable.

It still has it's original finish and cloth covers to the tips (though a little dog-eared).

Thanks again,

Steve

[Dave]

Yes, the Y120 is the drawing number for AVRO. It was applicable to the 120 HP Beardmore and lists it as "Martinsyde G100/102", so it could have been for either model.

It sounds like a nice collectible. Don't try to make it any nicer....

[StevieB]

No, the renovation is beyond my talents!

The propeller is in 2 halves, dissected very neatly diagonally through the hub, from back/left to front/right so when viewed front on it looks as if it's one piece. This looks to be designed this way - there is certainly no saw marks and the edges are perfect. I know some manufacturers made props in 2 halves, is this such a prop?

Sorry for all the questions, I can't find much about this prop (or on the aircraft type in general. Certainly no decent photographs).

Steve

[Dave]

No, the renovation is beyond my talents!

The propeller is in 2 halves, dissected very neatly diagonally through the hub, from back/left to front/right so when viewed front on it looks as if it's one piece. This looks to be designed this way - there is certainly no saw marks and the edges are perfect. I know some manufacturers made props in 2 halves, is this such a prop?

Sorry for all the questions, I can't find much about this prop (or on the aircraft type in general. Certainly no decent photographs).

Steve

I can't imagine manufacturing a propeller in separate halves. There is tremendous stress at the hub and the risk of separation is catastrophic.

There are a few small pics of both models on Rosebud's page, about 2/3rds down on the left column.

[Bob Gardner]

'Morning Steve,

Welcome to the forum.

The Aeronautical Inspection Department (AID) was formed in December 1913 to inspect materiel used by the newly formed Royal Flying Corps. Everything connected with flying was subject to test or examination.

This included;
raw materials such as baulks of timber and rolls of linen fabric long before they became parts for aircraft.
ancillaries such as tyres, radiators, rigging wires.
spars and longerons, paint and glue etc.

Generally props have four AID stamps which were added during various stages of manufacture. Each inspector had his own stamp. Often two inspectors stamped a prop twice to make up the grouping of four stamps. In effect these stamps were certificates of airworthiness.

I started collecting details of these stamps a few years ago and am building up a database of them, but this will not identify more than an individual inspector from a particular maker.

If any forumites have a WW1 British prop with clear AID stamps, I would be grateful if you could send me details of the prop, the data stamped on it and of the AID stamps.

With kind regards,

Bob