Achates DD

The complete A-I classes built on a year by year basis with one letter per year for naming, slowly replaced the older destroyers of the S-W classes as the Royal Navies premiere destroyers. My biggest problem with these ships is the low angle 4.7" gun that was retained by the Royal Navy right through to the much later S class of 1943. The RN did not even upgrade the mounting to an AA mounting. All of these destroyers AA capability was severely reduced. My aim in this AU is to rid the RN of the idiots that kept this policy going past 1933-34 when the DP guns of 4" and 4.5" were introduced. Even the single 4.7" AA mounting used on the Nelson type may have been better, but that mounting looked too heavy for use on destroyers. To this end the A-G class destroyers are going to need a revamp 1938+ to get rid of the 4.7"s and replace them with either single or twin DP guns.

War modifications (from Wiki)

(This information is a guide only from that other timeline we do not talk about here) It is unlikely that the early war losses Codrington, Acasta, Acheron and Ardent received any major alterations. In 1941 the surviving ships had the after funnel cut down in height and the after torpedo tubes replaced by a First World War era QF 3-inch (76 mm) 20 cwt anti-aircraft gun on mounting HA Mk. IV; a somewhat token addition. More of an improvement was landing 'Y' gun and the minesweeps and fitting Asdic and racks and throwers for a 10-pattern depth charge salvo, 70 rounds being carried. Two 20 mm Oerlikon guns were fitted, one in each bridge wing. Achates had 'A' gun replaced by a Hedgehog anti-submarine (A/S) mortar and had the centimetric Radar Type 271 for detecting surfaced U-boats. Others had metric Radar Type 286F or 290 added, the former of which had a fixed antennae array and required the ship to be turned to change the bearing down which it scanned. By 1942, the Canadian ships generally had 'B' and 'Y' guns removed, Radar Type 286 added, no torpedoes, a 12 pdr gun, six single 20 mm Oerlikon guns and stowage for 141 depth charges.

The four Southern African ships were completed in early 1931 and were transferred to SAN as escorts to the new battlecruiser Transvaal. The ships were used during their war service as escort command ships to the older M, R, & S class destroyer escorts. The Beagle shown above was typical of the SAN 'B' class destroyer conversions.

By 1943, Antelope had Radar Type 271, and Type 286 and 290 sets, where fitted, were replaced with Type 291. The 12 pounder gun was removed around 1943 and High Frequency Direction Finding (HF/DF, or "huff-duff") was generally added. The single 20 mm guns in the wings were replaced by Mark V powered mountings for twin weapons, the singles replacing the ancient 2 pounder guns amidships. In 1944 Active, Anthony and Antelope receiving a pair of 6 pounder / 10 cwt QF Mark I guns on a Mark I* mounting in lieu of 'B' gun. This automatic weapon was fitted for dealing with E-boats on east coast duties.

Most of the classes kept at least one set of four torpedo tubes as it was felt that the escorts may be needed to launch a torpedo attack on a Germanic States raider. As gun armed only DD's they would have been made mincemeat of, with torpedoes they had teeth that had to be respected.

Achates as ASW destroyer with Hedgehog forward and more depth charges aft and replacing after torpedo tubes.

Displacement	1400 tons std, 1900 tons full load
Length	321 ft
Breadth	33 ft
Draught	12 ft
Machinery	2 shaft steam turbines, 38,000shp
Speed	35 knots
Range	6000 miles at 15 knots
Armour	nil
Armament	2/4 x 4" (4x1, 2x2, 2x1) 4 x 2pd (1x4) 2 x 40mm (1x2) 2/4 x 20mm (1/2x2) 1 x Hedgehog (on some)
Aircraft	nil
Torpedoes	4/8 x 21" (1/2x4)
Complement	150
Notes