Key.Aero Network
Register Free

Page 1 of 2 12 LastLast
Results 1 to 30 of 40

Thread: Who invented C/N?

  1. #1
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213

    Who invented C/N?

    I am wondering about the origins of the term C/N for Constructor's Number. It has been suggested that it was first coined by Air Britain to describe the serial number assigned to an airframe by its manufacturer and to differentiate that number from a subsequent "serial number" as assigned by the military. So who was first to use it and when?

  2. #2
    Join Date
    May 2012
    Location
    Preston, Lancashire
    Posts
    341
    I would assume that this followed on from ship-building practice, where the builder would allocate a 'ship number' or 'yard number'.

  3. #3
    Join Date
    Jun 2014
    Location
    Cheltenham, Canada
    Posts
    89
    German manufacturers used 'werke' numbers that differed from tail/service numbers during WW1. I do not know what British practise was during this time period.

    Regards
    John

  4. #4
    Join Date
    Nov 2008
    Location
    Lancashire
    Posts
    887
    I'm sure that Ron is not suggesting that manufacturers lacked such a system before Air Britain existed, merely the use of the actual term C/N for clarity, in place of the variety of such terminology.

    However, as far as I know there was no German service numbering system that existed alongside manufacturing werke numbers, at least until late in the war when the system was standardised to avoid duplication. I suspect this is confusion with the radio call sign (four letters) issued to all German aircraft, which differed from the letter/number/two letters carried by operational units.

  5. #5
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    Thanks to all who have responded.

    Graham assumes correctly that I am trying to ascertain the origins of the term "C/N" as a descriptor for the serial number issued by the manufacturer.

  6. #6
    Join Date
    Aug 2004
    Location
    Not far from here!
    Posts
    1,731
    C/n was used by the aviation registration body in the U.K. pre WWII. The term certainly was not introduced by Air-Britain! If you use the CAA site and look at the following link to the first card recording the registration for example of G-ACTF you will find the term “Constructor’s Number” already in use.

    https://cwsprduksumbraco.blob.core.w...r/G-ACTF-1.pdf
    "Be who you are and say what you feel because those who mind don't matter and those who matter don't mind."(Mary Baker Eddy)

  7. #7
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    Consul

    Thank you for that most helpful response. Am I interpreting that document correctly if I deduce that the form (C.A. 113) was introduced by the Air Registration Board in October 1938 (10/38) and that the details for G-ACTF were retrospectively transcribed from a register to the new card (the stamp on the card is illegible). This would date the earliest documented use of "Constructor's No." at October 1938 but presumably it could have been in use earlier. Do we know what term was used in the preceding "Register"? We have at least eliminated the Air Britain furphy.

    Rgds

  8. #8
    Join Date
    Dec 2008
    Posts
    855
    hi morning,
    a interesting question, I've just had a look on the CAA site G-INFO, when I entered G-EASD the aircraft details have serial number E5. Further down the entry is view registration details, and again view entry for pre 1986, this gives the photocopy of the original registry card which then gives construction number E5 registered 26-3-20...
    The entry for G-EAAE a HP.O/400 ex airforce is on the aircraft details page its given as serial number HP16, and its pre 1986 original card its c/n number is D8350, its RAF serial...

    regards,
    jack...

  9. #9
    Join Date
    Apr 2012
    Location
    Leavesden
    Posts
    520
    For HP O/400 G-EAAE the 'HP.16' is it's Fleet Number, nominally in the Handley Page Transport fleet, but the list also includes a number of aircraft that HP sold overseas (possibly intended for local HP-sponsored airlines). This was used briefly as the company had become impatient with the international efforts to regularise civil registrations, and found the use of the original RAF serial unwieldy (and highlighting the war-like origins of the aircraft was unwelcome). As HP invented and re-invented their airline aspirations, and as O/400 derivatives proved themselves rather fragile in airline service, a number of their aircraft became 'bitsas' (i.e. bits of this, bits of that) and I don't think there was ever at that time a single 'works' number that was separate from an externally visible identity.

  10. #10
    Join Date
    Dec 2008
    Posts
    855
    hi,
    thanks LaztB for the extra info always useful. My 2 examples were of the earliest civil registrations I could find, and from the CAA cards of these 2 registered in 1920, the card has construction no. printed on...


    regards,
    jack...

  11. #11
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    Thanks everyone for the ongoing contributions. It would appear that the earliest recorded use of "Constructor's No." is the ARB card Form C.A. 113 which was introduced in October 1938 (See Post #6). Evidently many aircraft which were registered much earlier than 1938 were transcribed to this new card and their identities recorded in the column headed "Contructor's No." These identities may or may not have been classified as Constructor's Numbers before they were transcribed to the new card. The objective now is to find a reference to Constructor's No. earlier than 1938.

    I am also interested to know if the term was ever used by an American manufacturer.

  12. #12
    Join Date
    Mar 2013
    Location
    Sydney, NSW, Australia
    Posts
    81
    Hi Ron et al.

    Trevor Boughton's Man and Aerial Machines had an article plus follow-ups on this subject many years ago. It covered British, Australian and American aircraft. I will dig it up and have a look...
    Let your soul stand cool and composed before a million universes – Walt Whitman
    http://vhjet.com

  13. #13
    Join Date
    Dec 2008
    Posts
    47
    A lot of people (including some in this thread) refer to something called a "construction number".
    Is this simply a corruption of "Constructor's Number" or does it have any valid basis? . .

  14. #14
    Join Date
    Mar 2013
    Location
    Sydney, NSW, Australia
    Posts
    81
    You could say the answer to that lies in what the constructor puts on the plate. Some read 'serial number'. Some read 'construction number'. Both are constructor's numbers.
    Let your soul stand cool and composed before a million universes – Walt Whitman
    http://vhjet.com

  15. #15
    Join Date
    Dec 2016
    Posts
    114
    Probably started with the first cars being made maybe?

  16. #16
    Join Date
    May 2005
    Location
    Aerospace Valley
    Posts
    4,466
    US were certainly using it by 1933
    If anybody ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me: It's all balls. RJM.

  17. #17
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    US were certainly using it by 1933
    ZRX61 Please clarify. Using what by 1933?

  18. #18
    Join Date
    Mar 2010
    Posts
    1,552
    Construction/Constructor's Number and Serial Number are NOT the same thing: c/n (whichever version you choose) refers to a manufacturer's sequence number, assigned by them.

    Serial number is usually the term used to indicate an in-service identifier for military aircraft in the same way as 'registration letters/marks/numbers' indicate civilian versions of same.

    Serial number is also the term used to describe components of an aircraft which usually have a finite service life assigned to them.

    Back on-topic I recall as a spotty pre-teen being told about 'con numbers' by an elder member of LAAS (remember them?), but at the time having no idea what it referred to. Nowadays in the industry we seem to use the term 'MSN' rather than c/n.

  19. #19
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    Construction/Constructor's Number and Serial Number are NOT the same thing
    Sorry Sabrejet but I can't agree with you there. There are many cases where the same number is described as a serial number or a constructor's number.

    Serial number is also the term used to describe components of an aircraft
    or indeed the entire airframe!

    It could be speculated that the use of "serial" to denote an identity assigned by the manufacturer as well as an identity assigned by a military customer created the circumstance where somebody decided to coin the term "Constructor's Number" to eliminate any confusion.

    My latest research into Australian government issued registration and airworthiness forms indicates that the term "Constructor's No." was in use as early as 1921. This suggests to me that British use of "Constructor's No." would have been earlier than 1921.

    The term "Manufacturer's Serial Number" was in Australian use (for an American aircraft) as early as 1941.

    Rgds
    Last edited by Ron Cuskelly; 22nd June 2018 at 23:00.

  20. #20
    Join Date
    Dec 2007
    Location
    BOLTON Lancs
    Posts
    1,757
    Apologies for being "picky" but surely the question should read, when did the term "constructors number" come into use.
    It is not a matter of "inventing" it.....

  21. #21
    Join Date
    Mar 2013
    Location
    Sydney, NSW, Australia
    Posts
    81
    Sabrejet, I agree with some of your comments, but not all of them. Serial number does not necessarily apply to the military equivalent of the civilian registration; it may be true in some services but in fact not for the RAF and RAAF. if you look at the record cards and such things, the form actually says registration (although often something like just 'aircraft'). The point is that the usual identifiers on the aircraft are actually registrations; The UK and Australian boards developed out of the same systems, and you have civil and military registrars and registrations.

    What you say about component serial numbers is absolutely true and extends to aircraft as well, and it just depends on what the manufacturer calls it. The point being what 'serial' means; these numbers are sequential and relate generally to the production sequence. Normally, an aircraft serial or construction number never changes, where as the registration, military or civilian, can change.

    Obviously I'm making generalisations and there are exceptions within the UK and Australia, and in some other countries this system just doesn't apply.
    Let your soul stand cool and composed before a million universes – Walt Whitman
    http://vhjet.com

  22. #22
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    Planemike

    The thread title "Who invented C/N?" was intended to catch your attention as indeed it did! The original post ended with the question:

    So who was first to use it and when?
    Thus far there have been many helpful replies for which I am thankful.

    Rgds

  23. #23
    Join Date
    May 2005
    Location
    Aerospace Valley
    Posts
    4,466
    ZRX61 Please clarify. Using what by 1933?
    Construction numbers.
    If anybody ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me: It's all balls. RJM.

  24. #24
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    ZRX61

    Can you please provide an example of the US using "Construction Number" by 1933? That would be a significant contribution to the discussion.

  25. #25
    Join Date
    Jan 2000
    Location
    Angels one-five over North Bucks.
    Posts
    10,775
    In use in 1928 in the UK

    Mark

    "...the story had been forensically examined and was deeply impressive. I knew that the whole story was a load of myth and baloney…"

  26. #26
    Join Date
    May 2005
    Location
    Aerospace Valley
    Posts
    4,466
    If anybody ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me: It's all balls. RJM.

  27. #27
    Join Date
    Mar 2004
    Location
    Dublin
    Posts
    275
    I the case of the Avro Cadet (1935) in the Irish Air Corps museum, the plate refers to the Manufacturers number.
    Tony K

  28. #28
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    ZRX61

    Thank you for that link to Joe Baugher's excellent site. There are plenty of instances of MSN but I can't find any instances of C/N. Am I missing something?

    Mark

    Thanks for that document. Can you read the form number at top left? If the form number incorporates a printing date I expect it may predate 1928.

  29. #29
    Join Date
    May 2005
    Location
    Aerospace Valley
    Posts
    4,466
    MSN is the same as a CN. Sometimes it listed as MSN, other times as CN.
    If anybody ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me: It's all balls. RJM.

  30. #30
    Join Date
    Dec 2004
    Location
    Brisbane, Australia
    Posts
    213
    ZRX61

    I'm afraid you have missed the point of the discussion. The objective was to establish who first coined the term "Constructor's No" or "C/N".

    That MSN and C/N represent the same number is well established. You appeared to be claiming American use of the term "C/N". I'll be very surprised if anyone can establish the use of "C/N" by an American agency or manufacturer.

    Rgds

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

 

- Part of the    Network -

KEY AERO AVIATION NEWS

MAGAZINES

AVIATION FORUM

SHOP

 

WEBSITES