Unknown three-blade propeller before 1944

[aerodieppe]

Today we recovered a three-bladed propeller.
It was hauled up off Dieppe in Normandy (France) 23 years ago.
Apparently there was a bullet lodged in the hub with the inscription 1943.
One blade is missing.
The length of a blade is 1m65.
Could you help identify this propeller and possibly the type of aircraft on which it was mounted?

Thank you in advance for your help.

 

[MiTasol]

Hamilton Standard 23E50 fitted to dozens of different types of aircraft

 

[aerodieppe]

Hamilton Standard 23E50 fitted to dozens of different types of aircraft

Thank you very much for the reference.
We still have to find the plane that crashed off Dieppe.

 

[MiTasol]

My apologies for the short reply this morning but I was just leaving home.

Michael Hope is the expert on those props as he is still working on them but to me it looks like a fast feathering cam in the hub which narrows that prop to one used on multi engined aircraft. The blade length is measured from a point inside the hub but Michael will know how much to add.

If you can clean up the engine gear attached to the back of the prop and get some good photos of that it will help identify the engine type which will further help ID the aircraft type. I think that I know what engine it may be but there is not enough detail in your photos.

Note also that the HS 23E50 series were used on civil and military aircraft and also made under licence in Britain and Japan and probably one or more European countries as well. Production started and finished well before and well after WW2 so there are many possibilities but the task is not impossible.

Part numbers and inspection stamps are always a great help but given the overall condition of the assembly I think that the only places you will find them are on those bearing cage(s). Give them a good GENTLE clean and see what shows up. A steam or high pressure water jet will not damage them but any abrasive cleaning will. Part numbers are usually stamped into the metal and serial numbers are rare but when included are normally engraved into the bearing on the front or rear face. Some manufacturers do like to be different though so the second clip below may be a part or serial number. Serial numbers are excellent if they match the engine serial number but less so if line sequence serials as us common (because the engine serial was often created on completion). With that particular type of bearing the part numbers may appear on the inner race, the outer race or the cage. In many cases they will all be different as they relate to the individual part. With some bearings the number relates to the whole assembly,

 

[aerodieppe]

Hello,
There's no hurry.
This propeller had been in a pond for 23 years to have its salt removed, as it had been recovered from the sea off Dieppe.
Thank you very much for your explanations and advice.

According to a Facebook group, I had this information: 'the propeller is a Hamilton Standard 23EX, from a multi-engine aircraft with a Merlin engine'.

Sincerely, François

 

[MiTasol]

Thanks for that info - it sort of confirms my suspicion that it was a Merlin engine but I would not completely rule out other RR engines like the Peregrine yet. Finding a part number for the bearing will identify the sub-model Merlin if that sub-model engine parts catalogue still exists.

Merlins with hydromatic props were fitted to a wide range of British multi engine aircraft including, but far from limited to, Lancaster, Halifax, Beaufighter, Mosquito, etc, etc.

The 23EX series were a subset of the 23E50 series of the HS Hydromatic propellers, built by HS in the USA, which were fitted with a spider designed to fit British engines with tapered propeller shafts (instead of parallel shafts like on US, Japanese and some European engines).

If it was a British de Havilland or other licence built propeller it would have totally different model numbers. For example on the British built Lancasters with RR built engines the two options were:

On Canadian built Lancasters with Packard Merlins and parallel shafts the prop (if built by HS) would have been a 23E50* where * is a code which identifies which type of cams, distributor, blades and other options are fitted. Again - with licensee built props would have a different type number.

 

[Engineman]

So, if the "blade" is an accurate 1.65m from the centre of hub to tip, that gives about a 10' 10" prop diameter, but if it is from the entry of the blade into the hub to tip, that would be in the region of another foot on the dia, about 11'10".
Does look like a Merlin reduction gear. An accurate tooth count might help.

Eng

 

[Michael Hope]

To tell if it was installed on a Merlin engine, i.e. "23EX" it used a smaller nut than the the 23E50, images from the parts manual of the difference in the nuts. If the diameter is about 11 foot 6 inches, and the narrow blade, i.e. not a paddle blade, and what appears to be right hand rotation, it could be a B-17, B-24, C-47. The Lancaster used a 23EX with 6519A-0 blades at basic diameter of 13 foot, similar in shape to the 6501/6507/6541, that were used on the F4U, TBM, P-47, DC-4.