Hawker dataplate and constructor numbers

Thanks for posting !  Could you confirm whether that plate in the nose gear bay or the main undercarriage bay?

It would be great to see a picture of this Hunter if you have one.

Cheers

DD

There is a Peruvian Air Force Hawker Hunter F.Mk.52 preserved at a local park in Lima. The plate reads 41H-670691

P&P, ref your #41. The machine represented would have been Gloster built. It must be make believe. Very poor for a place like Duxford. I have never seen G1 or 40H before. A CCF connection? I doubt it very much and certainly not for that early production machine.

Interesting Philip that the floats on the Supermarine have a further /B7 number, I wonder if this is Shorts?

P&P, ref your #37 post, what evidence do you have for Gloster using G3? All Gloster Hurricane material I have found so far uses G5. It is easy to confuse a ‘3s’ and ‘5s’ in the style of lettering used in the 1920s to 1940s; could that be where G3 has slipped in?

Thank you Sirs. So far :

B1 – Bristol Aeroplane
S2 – Saunders Roe
G3 – Gloster Aircraft
S4- Armstrong Whitworth

41H – Hawker Aircraft

Who else was making Service aircraft in the UK in 1928 ?

Westland, Vickers, Supermarine, Fairey, Handley Page… any photos with a Component Log number showing on a Component on the right hand side…

S2 is Saunders-Roe

S4 was Armstrong Whitworth

DD

Just a further hypothesis on Component Log numbers, where 41H refers to Hawker Aircraft. By finding a number of high resolution original images of 1930’s service aeroplanes the code B1/xxxxx can be seen on Bristol Bulldogs and G3/xxxxx on Gloster built Hart biplane components or Gloster biplanes. So do these codes refer to Air Ministry designations for ‘approved’ suppliers, where Bristol Aeroplane was first on the list, Gloster third and Hawker 41st, understanding that Sopwith Aircraft may have been number 2, but by the time the post WW1 Hawker Aircraft company was formed from the bones of Sopwith, there were already 40 other suppliers on the list. Was Sopwith S2/ or S4/? In general, these codes are displayed on the right hand side of interwar aircraft, on all major components : fin, rudder, mainplanes, ailerons. Has anybody seen any photos of interwar aircraft with Component Log numbers displayed that could elevate or enervate this theory.

Noice.

Another one

Tag on Jack Macdonalds Demon scarf ring.

Hi P and P

I was just clarifying for the sake of standardisation of terms,aviation having muchly its own language and terminology.

The GAF paperwork you referred to in post #30 would possibly be more usually called Component Record Card or Component Log Card in the UK.
The various Hangars I worked in over the years usually referred to them as Log Cards although of course we did not always use the ‘official’ name for things.

A Release Note for older aircraft might be termed as…

Release Note = Certificate stating that the material or component to which it relates complies with appropriate standards and is therefore suitable for use.

rgds baz

Bazv, thanks for clarification – I will rephrase the intent of the information as being ‘Release Serial number’, in that the corresponding 41Hxxx number provided traceability.

GAF Canberra paperwork is not on a form titled ‘Release Notes’ but a blank card with a number, a component description, eg Rudder, and record of operations done to that component, which I have taken the liberty to call a Release Note, but should more accurately be called a Manufacturer’s record.

Just to re clarify some of the details from the last 5 years or so.

Every separate reasonably major assembly will have 41H in its unique component/item SERIAL number – clearly marked as Serial Number in the image posted in post #28.
A release note would normally be something totally different.

In the UK for Hawker items it would be fairly normal for a reworked/reconditioned component to have a letter ‘R’ added in to to the serial number to denote repair/rework/recondition,I am now retired so cannot go looking at interesting components any more LOL.

Just to close this off in case anybody looks at this in 2035 :

1. After looking through boxes of historical Release Notes used in the construction of Australian GAF (English Electric) Canberras from the 50’s, it is evident that great volumes of paperwork, identified by a Release Note number, were retained for each removable structure in the Canberra. It is surprising that these Release Notes remain for RAAF Canberras, as it is reasonable to assume a Constructor or Service would dispose of these once an airframe was obsolete. They take up a lot of room and serve no commercial purpose. A number of boxes of these are, however, to be found in the Archives of ANAM Moorabbin in Australia. For the sake of resolving the Hawker question, the keeping of Release Notes for removable/replaceable structures such as fins, rudders, ailerons AND fuselage is hypothesised to be British Constructor practice.

2. After looking at numerous historic photographs of prewar Hawker biplanes, where sufficient resolution exists, 41Hxxxx numbers are painted on the underside of all removable upper and lower wings and elevators and on the starboard side of rudder, fin and fuselage near the cockpit. It is hypothesised that the 41Hxxxx number is the Release Note number.

3. This hypothesis is supported by the finding of small dataplates on the remains upper and lower wings, elevators, fins, rudders, displaying the 41Hxxxx numbers, example pictured below. Data plates show Release Note and relevant drawing and Issue number, consistent with traceability. These plates have been identified on Hawker biplane remains in the UK, NZ and Australia. Where up to 11 individual, removable structures may be provided on each biplane, all with 41H Release Note numbers, a production run of 2,851 biplanes would require 31,361 Release Note numbers, in between other Hawker products. An Australian Demon Scarff ring exists which shows a 41Hxxx dataplate fixed to the Scarff ring, so there may be more numbers generated. This scale of number helps to reconcile the larger Fuselage dataplate numbering sequences, where sequential numbers are allocated from a Release Note register, but two biplanes built side by side during the same period may have up to 22 numbers of difference on a Fuselage dataplate. In general, a sequential Release Note register would issue numbers or blocks of numbers roughly aligning with blocks of Production. In general a Mk I Hurricane Release Note may be 41H100xxx, a 1935 Hind is 41H56xxx and a 1930 Hart might be 41H18xxx.

4. Within this Release Note system, a Hawker biplane identity may be defined by a list of 11 Release Note numbers, or for simplicity, a Master Release Note number for fuselage, being the Constructor’s Number, repeated in paint on starboard side fabric near the pilot’s position, and on the brass larger dataplate fixed on the portside under the instrument panel, in case of fire.

5. The Hawker Drawing Office handbook, in dealing with the allocation of drawing numbers, rules that a Drawing Number Register be kept, where numbers are allocated ‘first in, best dressed.’ No blocks of drawing numbers are reserved for particular aircraft. Australian Demons were retrofitted as trainers after 1936, with Australian Demon remains showing 1935 some parts as A56xxx while later retrofitted trainer parts show A91xxx, beginning to fall within Henley and Hurricane part numbering blocks, supporting this sequential allocation of drawing numbers. It is hypothesised that Release Note numbers followed the same rule, as it is simple and functional.

6. In order to confirm these theories, the finding of original Hawker Release Notes, and the matching of these to a high resolution, starboard photograph of a Hawker biplane displaying painted 41H numbers would be required. Alternatively a Production Office Book detailing Release Note number allocation practice in the period 1929-1939.

7. High resolution images of Hawker biplanes manufactured for the Persian government show the same Farsi script painted in the positions of 41H Release Note numbers. In this case, for a limited production run, Hawkers seems to have adopted a Release Note system where each elevator, rudder, aileron, wing and fuselage is numbered with the same Persian Service Number, for simplicity. For modern restorations of Hawker biplanes used in some foreign services, marking these components with foreign service numbers appears to be historically accurate.

8. For Australian Demons, based on high resolution images, 41H numbers within a ‘band’ of numbers appears to be historically accurate. A remnant fin, remanufactured by 2 Aircraft Depot in Sydney, has its own 2AD Release Note number in place of the usual 41H number. A remnant Avro Cadet fin, serviced by Clyde Engineering in Sydney, has a painted CECxxx (Clyde Engineering Company) in place of the usual 41H number on a Demon fin. This supports the hypothesis that 41H numbers are Release Note numbers, a system adopted by RAAF 2AD and CEC for traceability.

9. To match a Service identity, with a removable component Release Note Dataplate in remains, would require the finding of an original Service Logbook, detailing a Service number and Release Note numbers listed as being incorporated within that airframe. In Australia, original Service logbooks for a range of WW2 Service Aircraft have been found, which detail the identity of removable components. It is hypothesised that this is British practice, which would have extended to Hawker aircraft, but no Australian Demon airframe logbooks have been sighted to date to support this.

10. No-one will really know, unless they are 130 years old.

At the risk of resurrecting an old thread I noticed that the Hawker Cygnet at Cosford bears the c/n 41H/632195. I don’t know if that relates to 1924 or its post-war restoration because G-INFO states it was c/n “1” with G-EBJH as “2”. The Hawker Hart, G-ABMR, is quoted as “H.H.1”
[ATTACH=CONFIG]254720[/ATTACH]

OK looking at a couple of Hawker Squiddeleys finest today…

41H is clearly marked as Serial number on the data plates.

I would deduce from the 5 plates I looked at that…

41H with no prefix would denote the particular item was built at a Main Site (ie not subcontract)

Hawk flying control component marked as…SNo B3-41H-4120328, insp stamp BGA, date 1980

= manufactured at Brough (insp stamp BGA = Blackburn General Aircraft)

Harrier T2 Airbrake marked as FLR-41H – 752326 = manufactured at Folland (Hamble)

Hawk Canopy marked as FLR-41H – xxxxxx (also built at Hamble )

I also checked 2 fuselages… prototype/preproduction only had 6 digit number…production fuselage had 41H prefix (built at Kingston)

rgds baz

dwg number

Having studied drawings, manuals etc for the Hawker Family I have found that even the data plates had a drawing number. These indicated where the plate was to be located, the layout, what was to go on it, what font etc etc. I could obviously be wrong but I am sure that 41H 68118 for the Hawker Hind, for instance, is simply the drawing number for the data plate (68118) in the Hawker Family (41H). 68118 fits nicely into the range of drawings that I have for the bi-planes and in particular the Hind (the Tornado & Typhoon starting around the 99000 mark).

On the dataplates in post 1 there are 5 boxes for information :

Serial Number 41H XXXXX

Drawing No. eg D 59048, relating to location of dataplate on a/c, eg Australian Demon has B57549-1, being gun ring assembly dwg, with dataplate actually affixed to gun ring, and corresponding dwg number listed in Australian Demon specifications.

Date (of acceptance by final inspection?)

Registration, in the case of UK registered a/c of 1930’s vintage, a ‘K’ or ‘L’ code, eg L7191

Inspectors stamp

So I believe that the 41H XXXXX is the construction number, though it cannot be a sequential numbering system as previously posted.
Somewhere in the XXXXX is type variant, factory location and some system for linking an a/c identity back to materials issued for the construction of the a/c, for forensic engineering purposes.
Each spar in the 1930’s aircraft had a separate identity and a separate dataplate that linked back to the raw steel batch used in its manufacture.
No doubt these records were kept as part of a sophisticated quality control system.

If the 41H code continued on to Harriers surely there is somebody still alive that can decode this Rosetta stone.

Ideally somebody has a doorstop which is a big thick book with all this information…… if it is a retired uncle, give him a beer and get him to talk !

DaveR

The data plates do have a drawing number on them, but they are same on each data plate for the same type/Mk of aircraft. I think the numbers referred to in the initial posting (e.g. 68118) are the manufacturer’s construction numbers for each individual machine.

Having studied drawings, manuals etc for the Hawker Family I have found that even the data plates had a drawing number. These indicated where the plate was to be located, the layout, what was to go on it, what font etc etc. I could obviously be wrong but I am sure that 41H 68118 for the Hawker Hind, for instance, is simply the drawing number for the data plate (68118) in the Hawker Family (41H). 68118 fits nicely into the range of drawings that I have for the bi-planes and in particular the Hind (the Tornado & Typhoon starting around the 99000 mark).