AA armament of Decoy and Tenedos in April 1942?

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Rob Stuart
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AA armament of Decoy and Tenedos in April 1942?

Post by Rob Stuart » 22 Apr 2021 12:37

The destroyers HMS Decoy and HMS Tenedos were present on 5 April 1942 when Japanese aircraft attacked Colombo. Tenedos was sunk but Decoy was not hit. Would anyone happen to know their anti-aircraft outfits? Did Tenedos have nothing but a single 2-pounder pom pom? Did Decoy have two such weapons, plus a 12-pounder or something similar?

TIA.

EwenS
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Re: AA armament of Decoy and Tenedos in April 1942?

Post by EwenS » 22 Apr 2021 20:59

Rob
I can't confirm Tenedos but Thanet from the same flotilla had only a single 2pdr in Jan 1942. (see Warship 2015 Night Action off Malaya)

Decoy, I can't track anything definitive. There is a photo purporting to date to 1939 that shows her with a 3" gun between the funnels, which was supposed to be her original AA armament. That was supposed to be replaced in 4 of the D class by 2pdr singles and in the other 4 by quad 0.5" but I've nothing to say which ship got what.

Given that all her wartime refits were at Malta, it is possible that Decoy never received a 3" gun in place of the aft torpedo tubes.

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Re: AA armament of Decoy and Tenedos in April 1942?

Post by Rob Stuart » 23 Apr 2021 17:06

Ewen,

I belatedly recalled yesterday afternoon that all of the warships hit during the raid on Colombo submitted reports on the damage sustained and so on, and upon checking my notes I see that the report from the CO of Tenedos, in ADM 199/623, states that the ship’s AA armament consisted of 1 single-barrel Mark II pom-pom (as your info indicates), 2 Oerlikons and an unspecified number of machine guns. (I would assume the machines were all .303 inch weapons.)

Concerning Decoy, I see now that the Wiki article at https://en.wikipedia.org/wiki/C_and_D-c ... ifications, which seems fairly well researched, says that (in reference to the D class as a group). "Beginning in May 1940, the after bank of torpedo tubes was removed and replaced with a QF 12-pounder Mk V anti-aircraft gun, the after mast and funnel being cut down to improve the gun's field of fire. Four to six QF 20 mm Oerlikon cannons were added to the surviving ships, usually replacing the 2-pounder or .50-calibre machine gun mounts between the funnels. One pair of these was added to the bridge wings and the other pair was mounted on the searchlight platform." (In Tenedos and Vampire the searchlight was moved forward to make room for AA guns to occupy its original position, so presumably this was also done for Decoy and her sisters.) However, Decoy may or may not have received all these changes by April 1942, so hopefully I can find out a bit more, and your response will help in this refard.

Thanks,

Rob

EwenS
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Re: AA armament of Decoy and Tenedos in April 1942?

Post by EwenS » 24 Apr 2021 16:33

Rob
I'll have another go at posting a reply seeing as my first effort has been lost in the ether!

The Wiki article gives a reasonable overview of the changes made to the A to I class ships. What it doesn't do is give a timescale for those changes. The latter part of 1940 sees mainmasts removed and generally 3" guns in place of after TT in most ships refitted in the UK. But were ships refits carried out overseas to the same standard? Maybe not, see my comments about Defender below. While Oerlikons were available from late 1940, they were in very short supply until 1942 (in Nov 1940 there were only supposed to be 100 fitted to ships at sea in the entire RN). For example the cruiser Hermione didn't receive her first 5 until a Nov 1941 refit at Gibraltar with Naiad getting hers a couple of months earlier. Ships in the Med in 1941 were sometimes using captured Italian equipment and / or passing weapons to and fro as ships arrived or left the Med for the Indian Ocean. It seems to me that if any of these early destroyers serving in the Indian Ocean in April 1942 got them then they were lucky ships indeed.

Decoy left the UK in late 1934 and didn't return until Oct 1942 when she underwent conversion to an escort destroyer and being passed to the RCN. She came out of that refit with a typical escort destroyer armament incl 6 Oerlikons, no 3" and only 3x4.7" and Type 271 radar on the bridge in place of the directors and a single set of TT. But I've no idea what she went in with, although I doubt it included 6 Oerlikons. In between most of her refits / repairs were overseas, being Malta from the outbreak of war. She wasn't refitted during her time in the IO from March 1942.

Another ship in the same position was Defender. There are plenty of photos of her around taken at the time of her sinking in July 1941. She had lost the mainmast, acquiring a short mast on the searchlight platform instead, and had the after funnel cut down as per Wiki. But she had quad 0.5" on the bridge wings and a 3" gun between the funnels, thereby retaining both sets of TT. She retained the searchlight but with no platforms for AA weapons abreast it. She did however have a platform overhanging the after TT just in front of X gun. What was on that I can't tell. Possibly a single Oerlikon or 2pdr. Definitely not what Wiki considers her outfit to be however.

Going back to Decoy for a moment, I've seen one source that says she may only have had 3x4.7" before her 1942/43 refit. Now on 13/11/40 she was bombed at Alexandria and Y mount was damaged along with much of the stern area. So there is a question. Was it removed and never replaced?

So the bottom line is that at present it is very hard to say with any certainty exactly what her armament was in April - Sept 1942, unless you can find something in her Ships Log.

At present I've now exhausted my resources about her.
Ewen

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Re: AA armament of Decoy and Tenedos in April 1942?

Post by Rob Stuart » 25 Apr 2021 22:42

Ewen, thanks very much for the follow-up.

A member of another forum has provided the following info:

Possible armament of HMS Decoy, after Lenton:

4x1 4.7in, 2x1 2pdr AA, 2x4 .5in and 5x1 .303in AA machine guns, 1 12pdr AA gun, 1x4 TT

Lenton says D class originally had 2x4 TT but that in 1941 (?) the after bank of torpedo tubes was replaced by the 12pdr and aft funnel was shortened and the mainmast was struck to improve that weapon's sky arcs

He also says that the .5in AA machine guns in the bridge wings were replaced by two 20mm AA but doesn't say when this was done



Based on his input and yours, I'm leaning toward saying the following in the article I'm slowly drafting on the attack on Colombo:

Little Information is available on the anti-aircraft outfit of the other destroyer present, Decoy, but she may have had one 12-pounder, two single-barrel 2-pounder guns of an unknown mark, two quad .5 inch machine guns, and five .303 inch machine guns.

I'm using the phrase "may have had" in view of the uncertainty about when Decoy was fitted with which guns.

If you have any further comment, please feel free to share it.


Many thanks,

Rob

EwenS
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Re: AA armament of Decoy and Tenedos in April 1942?

Post by EwenS » 26 Apr 2021 16:02

Rob
I would look at it this way. The AA armament of the D class on completion was supposed to be a single 3” between the funnels plus quad 0.5” on the bridge wings. But due to delays in producing the latter 4 ships (not Decoy) got the 2x2pdr in lieu. All per Wiki. I have trouble believing Lenton with 2x2pdr AND 2xquad 0.5”. That is a very heavy light AA battery for any RN pre war destroyer.

In theory the 3” originally fitted was supposed to have been removed pre war, but the photo evidence from Defender shows that might not be true for all ships.

We know that aft torpedo tubes were being replaced by 3” guns as a general rule (but not Defender).

And we know that single 20mm were becoming available in the Indian Ocean area in spring 1942 (see Tenedos)

So my best bet would be 4x4.7”, 1x3” (either between the funnels like Defender or in place of the aft torpedo tubes, probably the latter), 2 quad 0.5” in the bridge wings and either 4 or 8 TT depending on where the 3” was mounted. Then maybe a couple of 20mm if there is no 3” gun between the funnels, either in place of it or on platforms alongside the searchlight. I just don’t see single 2pdr and quad 0.5” at that time.

I did come across a photo of one of the E class supposedly taken in March 1942 in the IO which only showed quad 0.5” between the funnels (plus there would have been the 3” in place of the after TT) as the only light AA armament. And another by late 1942 had 2 singles added.

Incidentally by way of comparison the new L, N & P ships were arriving in theatre at that time fitted (or in some cases refitted with) 4x20mm singles. That is about the heaviest you will get at that time.

It is interesting to note that while Dorsetshire had 9 single 20mm at the time of her sinking, Cornwall had none. All goes to show how lucky Tenedos was if she really did get 2, or perhaps just an indication of increasing availability.

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Re: AA armament of Decoy and Tenedos in April 1942?

Post by Rob Stuart » 26 Apr 2021 23:12

Ewen,

Could I first of all ask what source you're basing the following comment on:

It is interesting to note that while Dorsetshire had 9 single 20mm at the time of her sinking, Cornwall had none.

Two years ago I wrote a 45 page article on the loss of Cornwall and Dorsetshire, and during the several months I spent researching this subject I found no evidence that either ship had any 20mm guns. My article is at http://www.combinedfleet.com/CornwallDo ... -Adobe.pdf and Table 2 includes the results of my research into their armament at the time of their loss. (The appendices and notes are at http://www.combinedfleet.com/Appendex_1 ... -Adobe.pdf.)

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Re: AA armament of Decoy and Tenedos in April 1942?

Post by EwenS » 27 Apr 2021 08:21

Rob
I lifted the comment about Dorsetshire’s AA armament from Raven & Roberts “British Cruisers of World War 2” Appendix 2: War Modifications p429 which states for Dorsetshire:-

“By early 1942: nine single 20mm fitted”

I’ve usually found that Appendix reasonably accurate when photos are available to back them up. But, I also see Friedman’s comments (p127 of his British Cruisers book) that you reference with the drawing by Alan Raven noting only the additional 2pdr aft.

I can only assume that 30 additional years of research between the two books turned up additional information.

If only the RN had, like the USN, taken more photos of their ships our research life would be so much easier. I’m very much an amateur historian, with only an increasing interest in the IO 1942 period thanks largely to your work (my main interest is 1944/45 in the IO/Pacific theatre), so I’m more than happy to bow to your superior knowledge. When I reflect on that supposed armament fit, it does in fact seem odd, as Cruisers refitting in the U.K. and the USA around that time were only beginning to get 7-9 Oerlikons, let alone a ship 9 months out of her last U.K. refit serving in the quieter areas of conflict at that time.

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Re: AA armament of Decoy and Tenedos in April 1942?

Post by Rob Stuart » 15 Jun 2021 12:19

EwenS wrote:
27 Apr 2021 08:21
Rob
I lifted the comment about Dorsetshire’s AA armament from Raven & Roberts “British Cruisers of World War 2” Appendix 2: War Modifications p429 which states for Dorsetshire:-

“By early 1942: nine single 20mm fitted”

I’ve usually found that Appendix reasonably accurate when photos are available to back them up. But, I also see Friedman’s comments (p127 of his British Cruisers book) that you reference with the drawing by Alan Raven noting only the additional 2pdr aft.

I can only assume that 30 additional years of research between the two books turned up additional information.

If only the RN had, like the USN, taken more photos of their ships our research life would be so much easier. I’m very much an amateur historian, with only an increasing interest in the IO 1942 period thanks largely to your work (my main interest is 1944/45 in the IO/Pacific theatre), so I’m more than happy to bow to your superior knowledge. When I reflect on that supposed armament fit, it does in fact seem odd, as Cruisers refitting in the U.K. and the USA around that time were only beginning to get 7-9 Oerlikons, let alone a ship 9 months out of her last U.K. refit serving in the quieter areas of conflict at that time.
Ewen,

Thanks for the detailed response (and apologies for this rather tardy reply to it).

I have a very favourable view of “British Cruisers of World War 2”, and it was of course an important source for my article. I think I must have been unconvinced that Dorsetshire had any 20mm guns, despite that fact that this book is well researched, because it was such an outlier. There was not even a hint in any other source that it may have had any 20mm guns, let alone nine, and if it had had that many then I can't say why it was apparently still carrying its two quad .5 inch guns in what would have been excellent positions for 20mm guns. In short, I decided to omit any reference to Dorsetshire carrying 20mm guns because their existence was unconfirmed.

For the same reason, I've now deleted all reference to the AA armament Decoy may or may not have been carrying when Colombo was attacked. Your posts in this thread have introduced enough doubt in my mind about what AA guns she may have been carrying that I think it's better to say nothing on that score than to provide unconfirmed info or add a metric ton of qualifications (e.g., "Decoy carried possibly X of this and maybe Y of that").

So thanks for your posts on Decoy. You've helped me avoid being "decoyed" into the minefield of dubious assertions and put me back into the swept channel of confirmed facts approach.

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