Identification propeller blade Hamilton 1940

[PEPA44]

Dear all,

I'd like your help in identifying a propeller blade which must date from the early '40s.
The bore in the axis of the blade root and the shape of the base would seem to be a "Hamilton standard".

Would it be possible, with the punches (DHA452…) and the reference (CM3320), to identify the aircraft to which this propeller blade would have been fitted?

I know that the LeO-453 also had a standard Hamilton propeller, but this blade seems to be older.

Thank you for your help.

 

[ThomasP]

The DHA over xx in a circle is a known inspection stamp for De Havilland Aircraft Company, Ltd.

De Havilland license produced Hamilton Standard designed propellers.

De Havilland produced propellers often had the stamp DHL over xx in a circle (DHL = De Havilland-Lostock, where the main production facility for De Havilland Propellers, Ltd was located). But the generic Havilland Aircraft (DHA) stamp was often used. I do not know how long DHA was used for the inspection stamps on DH propellers, but DHA was quite common as an inspection stamp on DH aircraft parts in general.

I think DHA was used when the final inspection was done by a central processing authority within the DH corporate structure, but I am not exactly sure how this worked.

 

[PEPA44]

The DHA over xx in a circle is a known inspection stamp for De Havilland Aircraft Company, Ltd.

De Havilland license produced Hamilton Standard designed propellers.

De Havilland produced propellers often had the stamp DHL over xx in a circle (DHL = De Havilland-Lostock, where the main production facility for De Havilland Propellers, Ltd was located). But the generic Havilland Aircraft (DHA) stamp was often used. I do not know how long DHA was used for the inspection stamps on DH propellers, but DHA was quite common as an inspection stamp on DH aircraft parts in general.

I think DHA was used when the final inspection was done by a central processing authority within the DH corporate structure, but I am not exactly sure how this worked.

Dear Thomas,
Thank you very much for this information.
Could you tell me on which model of De Haviland aircraft this blade was installed and What if it dates back to the early '40s?

 

[ThomasP]

Sorry, but I do not have access to very many specific DH blade drawing numbers, and neither of the numbers you posted above are on my lists.

 

[PEPA44]

Sorry, but I do not have access to very many specific DH blade drawing numbers, and neither of the numbers you posted above are on my lists.

No problem. Thank you Thomas

 

[mjfur]

How about a DH Beaver?

 

[ThomasP]

Hey PEPA44,

Where was this blade from? The reason I ask is that the DHA stamp may be specific to De Havilland Aircraft of Australia. The A in the DHA would be to differentiate the more usual DH over xx in a circle or sharp-cornered triangle of De Havilland Aircraft of England from the De Havilland Aircraft of Australia inspection stamps. I noticed what look like a couple of inspection stamps shaped like upside-down triangles with rounded corners on the flange of the propeller, and I think these are indicative of De Havilland in Australia. According to Wikipedia, De Havilland of Australia began manufacturing propellers in late-1930s, for use domestically and by De Havilland of England.

"de Havilland Australia - Wikipedia"

Also, if you could measure the overall length it might help eliminate some aircraft types as it would be too large or small.

 

[PEPA44]

Hey PEPA44,

Where was this blade from? The reason I ask is that the DHA stamp may be specific to De Havilland Aircraft of Australia. The A in the DHA would be to differentiate the usual DH over xx in a circle or sharp-cornered triangle of De Havilland Aircraft of England from the De Havilland Aircraft of Australia. I noticed what look like a couple of inspection stamps shaped like upside-down triangles with rounded corners on the flange of the propeller, and I think these are indicative of De Havilland in Australia. According to Wikipedia, De Havilland of Australia began manufacturing propellers in late-1930s, for use domestically and by De Havilland of England.

"de Havilland Australia - Wikipedia"

Also, if you could measure the overall length it might help eliminate some aircraft types as it would be too large or small.

Thanks for your message.
The blade comes from Metz in France and is about 1.80 m long.

Have a nice Sunday Thomas.

 

[ThomasP]

A 1.8m (~5'11") long blade would indicate an approximately Ø3.81m (Ø12' 6") propeller (I think).

One pre- and early-war aircraft that used a DH Ø12' 6" prop was the Fairey Battle light bomber. I am sure that there are several other aircraft types that used this size DH prop.

 

[Geoffrey Sinclair]

Information received,

Clearly a dH blade and on first view looks to me like a hydromatic. Given the blade length it is clearly from a bomber.

In respect of the Australian company supplying blades to Britain. I have not found a reference to this in any of the Air Ministry or dH documentation and history that I have read and would be surprised if this happened to any significant degree or at any time after 1940 although this is not to say it did not occur.

I have previously seen 'DHB' inspection stamps and wonder if 'DHA' and 'DHB' differentiated between Enfield and Lostock?

Unfortunately the full blade number is corroded, although it seems to me that the numbers 800 form part thereof. If so the two initial options are P55800 (RH bracket)or P455800(RH hydromatic), with a full diameter of 13ft. Also note the '/C' after the number 800.

According to my listings the particular aircraft on which this (hydromatic P455800/C) blade was used is the Lancaster III with Merlin XX/20/24/28 engines.(One of my references states blade drawing number P455800/A was also used).

As a passing comment, shortened versions of this blade were used on the Wellington.

 

[PEPA44]

A 1.8m (~5'11") long blade would indicate an approximately Ø3.81m (Ø12' 6") propeller (I think).

Information received,

Clearly a dH blade and on first view looks to me like a hydromatic. Given the blade length it is clearly from a bomber.

In respect of the Australian company supplying blades to Britain. I have not found a reference to this in any of the Air Ministry or dH documentation and history that I have read and would be surprised if this happened to any significant degree or at any time after 1940 although this is not to say it did not occur.

I have previously seen 'DHB' inspection stamps and wonder if 'DHA' and 'DHB' differentiated between Enfield and Lostock?

Unfortunately the full blade number is corroded, although it seems to me that the numbers 800 form part thereof. If so the two initial options are P55800 (RH bracket)or P455800(RH hydromatic), with a full diameter of 13ft. Also note the '/C' after the number 800.

According to my listings the particular aircraft on which this (hydromatic P455800/C) blade was used is the Lancaster III with Merlin XX/20/24/28 engines.(One of my references states blade drawing number P455800/A was also used).

As a passing comment, shortened versions of this blade were used on the Wellington.

Many thanks Geoffrey for the identification.

Thanks also to Thomas for advanced on identification.

Stéphane

 

[elbmc1969]

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