1923 Tubular Skeleton Bomb carrier and bombs?

[Mattoo]

Hello, this is my first posting here and might be back with a few more questions like this as I am creating illustrations for a book on interwar aircraft.

In this instance I have this unproduced Supermarine drawing from 1923 showing a tubular skeleton bomb carrier with a 250lb and 500lb bomb attached. Can anyone identify the two bombs and the bomb carriers?

I have the Putnam Armament of British Aircraft and also the Air Ministry Details of Aerial Bombs 1918 (IWM reprint). The latter includes a drawing of the mark 1 250lb bomb but it states it is already obsolete (1918) - indeed the Supermarine drawings shows a slightly different bomb and fins.
There is no 500lb bomb listed in the book but there is a mark 1 520lb bomb which matches quite closely that shown in the Supermarine drawing. However again it states it is already obsolete by 1918 - and this drawing is from 1923.

Any ideas on identifying and how I might find further reference on the two bombs and bomb carrier would be most welcome. Even finding modern day existiing examples of the tubular bomb carrier for reference has proven quite difficult.

 

[butterfly]

Hi,
I am just looking through a book 'bombs gone' by Wing Commander John A. MacBean and Mahor Arthur S. Hogben.
In it it says;
An Air Staff requirement for a GP bomb or series of bombs was first presented in 1921 and, in April 1922, a development programme was approved for a range of this type. It was stated that a provisional range of 50, 120, 250 and 500lb bombs would help to standardize type and shape, simplify design and manufacture, and provide a reasonably efficient weapon against all types of unarmoured or lightly protected targets.....

it goes on to say that;

In 1925 a small number of 250 and 500lb bombs existed, albeit inert-filled. Dropping trials showed that their tragectory and stabilitiy in flight was superior to existing war-time bombs of similar weight.

So it would seem from this that the drawing is an early reference to these bombs? ...and that at the time of the drawing they were still in the experimental stage?

not sure if this helps, but it is at least a start...

regards Kev

 

[Bonnex]

From Armament Training Manual AP1243 Part II Bombs, Pyros, Bombsights etc 1927

 

[Mattoo]

Thanks guys. The Mark II 250lb bomb you've got there Bonnex looks very close indeed. That will do me!

The Mark I 520lb looks like the one in the 1918 Air Ministry book and this is where I got stuck as the forward part of the cylindrical stay(?) would interfere with the mechanism (crutch?) as shown in the Supermarine drawing. So Butterfly, you may well be right in that what we have here is an experimental 500lb bomb in the drawing. Unless I can find a picture of that I may have to adapt it to the 520lb Bonnex has shown.

Thanks very much indeed!

 

[eodda]

The GP series of bombs referred to in 'Bombs Gone' were more streamlined than those of the WW1-style designs shown above. I think that Bonnex has got it right: the bombs shown in the Supermarine drawing are schematic outline shapes to show how typical bombs of the period would fit onto the two carriers. The purpose of the brackets at the nose and tail of the 520lb bomb may well be auxiliary crutches (the main one seems to be at the release unit), but they may also have been to prevent the arming vanes of the pistols/fuzes from rotating in flight, in which case they would have interferred with the arming vanes on purpose.

I have a reprint of AP908 - Particulars of Aircraft Armament, dated 1925, which shows both the RAF 520 lb and the RL 520 lb bombs to be in service at that time.

Regards

eodda

 

[butterfly]

According the the book 'Bombs Gone' the trials with the 500lb bomb appear to have been carried out a good deal later than when the concept was approved in 1922. The info within the book gives no specific dates, but does say that certainly it was after 1927......(and I suspect it was much later than this) - this may explain why there is no mention of it in the book Bonnex has posted from 1927. It would appear the 500lb bombs were still undergoing tests - I think things only speeded up with the storm clouds gathering before WW2.

I wish you luck with your illustrations....
regards Kev

 

[Mattoo]

Okay thanks, I'll stick with the Bonnex recommendations and make amendments to that extra crutch on the 500lb carrier - I might just remove it as it gets in the way.

That brings me to the next point. I've made a good search of Hendon and Duxford for existing carriers of this type so that I could get some photos, but without any luck. In all contemporary photos they're painted black and almost impossible to make anything out. Any recommendations for existing examples?

 

[Bonnex]

There were a considerable number of experiments conducted on aerial bombs during the 1920s. The 1927 Armament Manual represents the in-Service state-of-play for that time but changes were inevitable during the next several years. I commend you to read the Annual Reports of the Ordnance Committee for the inter-war period which are available at The National Archives under SUPP 6.

Royal Air Force Aircraft Bombs are generally not(*) an area of study for me but I am interested in them up to about 1926 when the responsibility for them passed from the Royal Army Ordnance Corps to the RAF's own Armament Officers (Info on this subject always welcome).


Thanks

(*) With the exception of MD1 designs

 

[butterfly]

Okay thanks, I'll stick with the Bonnex recommendations and make amendments to that extra crutch on the 500lb carrier - I might just remove it as it gets in the way.

That brings me to the next point. I've made a good search of Hendon and Duxford for existing carriers of this type so that I could get some photos, but without any luck. In all contemporary photos they're painted black and almost impossible to make anything out. Any recommendations for existing examples?

Hi Mattoo,
I was just wondering about the comment you made about 'removing' part of the carrier from the drawing....given that this drawing is from a date you are intending to cover, do you think this is wise? I have learnt over time that just because something doesnt fit into the 'box' it doesnt mean to say that it wasnt accurate...........at the same time I have also learnt that not everything that you come across is 100% accurate. One thing I can be sure of is that at the date of the drawing the concept of a 500lb bomb had been accepted, either the drawing is showing how a 500lb bomb would fit or that the 500lb bomb closely resembled the 520lb bomb of earlier date - or - that the label ought to read 520lb bomb and not 500lb (an error perhaps??)
As someone pointed out the added crutch could be for holding the fuzing mechanism, removing it from your illustration would make the drawing inaccurate, would it not? Hopefully there may be a photograph out there that helps fill in the blanks??

again all the best with everything - Kev

 

[Mattoo]

Hello,
I'm just making the best of what I have, which is wise only in the context of the time available (I have about a dozen images to do) and that these are secondary elements, it's more about the planes. It should also be noted these are just concept drawings and a long way from construction drawings. Many of the drawings are very shoddy indeed.
At the moment I'd either have to alter the Mk.I 520lb bomb and guess what the 500lb might have looked like or alter the carrier to fit the 520lb drawings available.

I'll see if there's any easy way at getting at the Annual Reports of the Ordnance Committee but I've been on those wild goose chases before with stuff from Kew.

cheers
Matt