The Hearne class brought in the first major upgrade to Antarctican destroyers for over 20 years. The change was from single to twin turrets for the main armament. The ships would keep the same hull but change the layout in many ways. Just one being going from two funnels to one which altered the look of the ships. A larger bridge was required to fit the full, larger director than that fitted to earlier classes.



The class was ordered in two groups of ten so that as with the earlier Muller class they could have five ship flotillas providing their own leader. This lasted till 1936 when the first of the new Ronne class Leaders were completed and matched with five of the Hearne or Muller class to have a six ship flotilla. With the Captain Noble class also being available for use as Flotilla Leaders, the numbers were altered to four destroyers and a leader.



The 40mm refits the class started receiving in late 1941, brought the ships right up to date. With one quad and four twin 40mm mountings replacing the previous 2 pounder and 20mm AA guns, space also had to be found for the radar predictors for each mounting. Where the twin 20mm had been sited above 'A' turret, a Hedgehog ASW mortar was fitted. Three different search and targeting radar were fitted on the masts and lastly the 5" gun director received its own radar assistance.

 

Displacement	1,700 tons standard, 1,950 tons full load
Length	359 ft
Breadth	36 ft
Draught	13 ft
Machinery	2 shaft, steam turbines, 40,000shp
Speed	35 knots
Range	6,000 miles at 10 knots
Armament	As completed 6 x 5" (3x2) 4 x 2pd (1x4) 6 x 20mm (1x2, 4x1)	Refits to 1942 6 x 5" (3x2) 12 x 40mm AA (1x4, 4x2) 1 x Hedgehog
Torpedoes	8 x 21" (2x4)	8 x 21" (2x4)
Complement	135	150
Notes	Hearne Clay Robinson Louis Armstrong Pep Greb Johnson Langford Duran Leonard Charles Moore Mayweather Wilde Paquiao Attell Ross Hagler Whittaker