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Bomb ID

Yes American made bomb, 50lbs MkIII (body absed on the shape of teh French Gros-Andreau bomb of ww1)
BTW the officer is no other than Billy Mitchell
50lbs MkIII.jpg
 
Looks to be one of the 25lb development series. This photo shows up in a number of period documents, but I don't think that this variant with the nose fuze was ever standardized and received a number. There was a lot of work on bombs during the war and the line of development is far from clear. I know that several people on BOCN have spent a lot of time tracking documents on these early bombs, but in my experience many of the the documents are inconsistent with each other and like now many variations were not documented well as they were dropped quickly. In Americas Munitions 1917-1918 Crowell reports that in Dec 1917 70,000 MKII 25lb bombs were initially contracted to be delivered by Martin-Rockwell (M-R) but in June the AEF informed that the bomb was too small to be of any use and the contract was cut down to 40,000 to be used for training of aviators. By Nov of 1918 36,840 were completed. This would seem to indicate that almost immediately development on this size of bomb would have been reduced or stopped, leaving this as a 1918? piece. I have seen recovered examples of these and the 50lb version which were still being expended in training post war, and had been adapted with wire loops around the body to allow for use on racks with two lug suspension systems. Maybe one of the folks that tracks these more closely can chime in with additional info.

IMG_0314.jpg IMG_0313.jpg
 
Thanks guys,
I thought to a 25 or 50 lb but I was surprised by the nose fuze (only saw standard bombs with tail fuze).
 
It is really difficult to tell the specific size from that angle/distance and mounted on the aircraft. The entire series is nearly identical in design so it could easily go either way. My feeling from my items is that it is a 25lb, but I've been wrong before. In my photo above you can see the 25lb, 50lb and on the floor is one of the 100lb.
 
If I understand correctly your problem, you are disturbed with this nose fuze. Effectively, from my document, the HE bombs 25 and 50 lb are tail fuzed, but, a little further, I find a 40 lb incendiary with is nose fuzed. (Document is in the moderation queue of the download page)


Yoda
 

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  • US MK I 40lb Inc-01.jpg
    US MK I 40lb Inc-01.jpg
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If I understand correctly your problem, you are disturbed with this nose fuze. Effectively, from my document, the HE bombs 25 and 50 lb are tail fuzed, but, a little further, I find a 40 lb incendiary with is nose fuzed. (Document is in the moderation queue of the download page)


Yoda

Interesting Yoda.
Same dimensions as 50lb HE.
I found on the web a picture of the sister, 40lb MK II Incendiary

40lb.jpg40lb 2.jpg40lb 3.jpg40lb 2 - Copie.jpg
 


The Mk series were developed on the basis of the French GA MMN bombs
- Gros Andreau bombs were the liquid Anilite explosive was replaced by MMN.
Such bombs became common in 1918 in the French Air service, as they avoided the many problems of the Anilite and its toxic effects for the crews.

The Gros Andreau were available in 10kg (120mm diameter), 25kg (155mm diameter) and 50kg (200mm diameter)

According to the Operational Records of French Bombing Squadrons, The 10kg (120mm) diameter had been the most commonly used in the war and after that the 50kg (200mm)

The GAMMN bombs could be fused in case of horizontal suspension with a Michelin nose fuse installed instead of the Gros Key
(used to puncture the separation between anilite and hydrocarbure inside the bomb at dropping time), or with a tail fuse Michelin No2, the Gros key being replaced by a vertical suspension key.

In 1918 these bombs became respectively 10kg GAMMN 25kg GAMMN and 50kg GAMMN
However only the 50kg GAMMN remained standard issue after 1918.

The bomb rack on the picture is of a type designed for a "50lb and over" order of bombs. The 25lbs typically used a multiple rack, and in any case was relegated after June 1918 strictly to exercise (and remained in such role till the end of the 1920s)
So it is most probably a 50lb or 100lb bomb.

So we may have here a very early Mk series bomb, still very similar to the GAMMN bomb, though the nose fuse looks definitively American

However, it's most probably a 100lb MkI MI as this bombs was, in the early 1930s, equipped with a nose fuse MkVII MI, while the 25bs and 50lbs were simply discontinued and eliminated from the stocks.

This is a drawing of such a bomb from a document by Henry Belot
100lb MkI MI Deminest.jpg

The 50lb had a length of 930mm and a diameter of 155mm (like its French model)
The 100lb had a length of 1257mm and a diameter of 200mm (here too like its French model)

BTW The early Mk series suffered from the same defects of the original GAMMN bombs - too thin metallic envelop, with too much soldering between parts - that led to the French abandoning them for better bombs.
 
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You had me until the suggested identification of the 100lb bomb - At that point I certainly disagree. There is an obvious length discrepancy, in addition you can make a comparison with the 25lb Cooper beside it. Billy Mitchell is identified as 5'11" tall (180cm), weighing 172lbs (78 kg), not small, but not a particularly large man. Making a size comparison with his hand, the bomb in the photograph could arguably be easily picked up with one hand and carried away. It is not the 100lb.
 
Agreed - this is most probably a 50lbs and not a 100lbs - The comparison with Billy Mitchell height is a very good point, as well as with the Cooper bombs behind.

BTW I found this in the Rick Stauber collection at the UXO archives, this is probably the drawing that has inspired Henry Belot

sketch-demobomb-100lbs.jpg
 
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Hello,
Could be this one :

50lb demonstration

50lb demonstration.jpg

The first photo of this post is consistent with a demo drop.
With good eyes the fuze on the bomb could be the MkXIV decribed in the doc
 
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Indeed it looks very similar but - demonstration??? bomb - a demo bomb was always the short form of Demolition bomb in US "technical literature" - from where does this picture comes from and what its text says about it?
 
Official US doc sheet B-2-1-6 (rewriting of a 1930 document ; because of the bad quality, I think diagrams are extracted from the original doc).

Description : BOMB, DEMONSTRATION, 50-LB., MK. I, AND BOMB, DEMONSTRATION, 50-LB., MK. I (Adapted for Old Mk. XIV Nose Fuze)

These bombs utilize the empty bomb cases of the bombs, incendiary, Mk. I. Fitting into the bomb case is
a black iron container which has its cavity, except that taken up by the booster, filled with titanium
tetrachloride. This chemical is a smoke-producing mixture. The bomb body is streamline in shape. The
only difference between the bomb, demonstration, 50-lb., Mk. I, and bomb, demonstration 50-lb., Mk. I
(adapted for the old Mk. XIV nose fuze) is that the nose adapter of the former has the
standard thread for the reception of the fuze, while the nose adapter of the latter has the Lowenherz
thread. For the two types of Mk. XIV fuze. It is used for demonstration and training
purposes only, in accordance with training allowances.
 
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