Halcyon-class minesweeper

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HMS Britomart (J22)
HMS Britomart secured to a buoy in Plymouth Sound
Class overview
Operators:  Royal Navy
Preceded by: Racecourse class
Succeeded by: Bangor class
Subclasses: reciprocating / turbine-engined
Planned: 22
Completed: 21
Lost: 9 (+1 constructive total loss)
Retired: 12
General characteristics for Reciprocating
Type: fleet minesweeper
Displacement: 815 tons (828 tonnes)
Tons burthen: 1,370 tons (1,391 tonnes)
Length: 245 ft 9 in (74.90 m) o/aii
Beam: 33 ft 6 in (10.21 m)
Draught: 9 ft (2.7 m)[1]
Propulsion: 2 × Admiralty 3-drum water-tube boilers, vertical compound reciprocating steam engines on 2 shafts, 1,770 ihp
Speed: 16.5 to 17 kn (31 km/h)
Range: 7,200 nmi (13,330 km) at 10 knots (19 km/h)
Complement: 80
Armament:

2 × QF 4 inch Mk.V (L/45 102 mm) guns
1 × mounting CP Mk.II
1 × mounting HA Mk.III

8 × .303 inch (7.7 mm) Lewis machine guns
General characteristics (Niger, Salamander)
Tons burthen: 1,330 tons (1,351 tonnes)
Length: 245 ft 3 in (74.75 m)
Propulsion: Vertical triple-expansion, 2,000 ihp
Speed: 17 knots (31 km/h)
Armament:

2 × QF 4 inch Mk.V (L/45 102 mm) guns, single mounts HA Mk.III
4 × .5 inch Mk.III (12.7 mm) Vickers machine guns, quad mount HA Mk.I

8 × .303 inch (7.7 mm) Lewis machine guns
Notes: Other characteristics as per reciprocating ships
General characteristics (turbine)
Displacement: 815 - 835 tons (828 - 848 tonnes) /
1,290 - 1,350 tons (1,310 - 1,372 tonnes) full load
Propulsion: 2 × Admiralty 3-drum water-tube boilers, Parsons steam turbines, 1,750 shp (1,305 kW) on 2 shafts
Speed: 16.5 knots (31 km/h)
Notes: Other characteristics as per Niger / Salamander

The Halcyon class was a class of 21 oil-fired minesweepers (officially, "fleet minesweeping sloops") built for the British Royal Navy between 1933 and 1939. They were given traditional small ship names used historically by the Royal Navy and served during World War II.

Design[edit]

There were 21 ships in the Halcyon class, built in two groups; the first using reciprocating steam engines, with steam turbines in the latter. They were generally smaller versions of the Grimsby class escort sloops. Niger and Salamander of the reciprocating group used vertical triple expansion engines, instead of the vertical compound engines of their sisters. As a result of the increased installed power they had a half knot speed advantage, even though they used slightly shorter hulls. The turbine ships used the same shorter hulls as Niger and Salamander, but with lower installed power, speed dropped back to 16.5 knots (31 km/h).

Gleaner, Franklin, Jason and Scott were completed as unarmed survey vessels, Sharpshooter and Seagull being converted to follow suit. They were all re-armed and deployed in their original role on the outbreak of war. Seagull had the first all-welded hull built for the Royal Navy.[2]

Service history[edit]

Halcyons served in Home waters, at Dunkirk, on Arctic convoy duty, and in the Mediterranean.

On 3 February 1940 Sphinx (Cdr. J. R. N. Taylor, RN) was sweeping an area 15 miles (24 km) north of Kinnaird Head when attacked by enemy aircraft. A bomb pierced the fo'c'sle deck and exploding destroying the fore part of the ship. She remained afloat and was taken in tow by Halcyon but steadily flooded and capsized and sank. The wreck was later washed ashore north of Lybster and was sold for scrap. The Commanding Officer and forty of the men were killed in the explosion.

Skipjack (Lt.Cdr. F. B. Proudfoot, RN) was attacked and sunk by a force of German dive-bombers off De Panne, Belgium on 1 June 1940. On board Skipjack were between 250 and 300 soldiers just rescued from the Dunkirk beaches during Operation Dynamo. Eye witness William Stone said "she just disappeared".[3]

Halcyons were pressed into service as anti-submarine escorts; this task slowly decreasing as the ships specifically designed for this task, such as Flower class corvettes, came off the slips. Halcyons accompanied most of the Arctic Convoys, serving both as minesweepers and anti-submarine escorts. Several spent extended periods working out of Soviet naval bases in Northern Russia, such as Murmansk. Four Halcyons were lost during this period.

Hebe and Speedy served in the Mediterranean as part of the 14th/17th Minesweeper Flotilla based in Malta. The minesweepers saw action during the Malta Convoys, Operation Torch, and Operation Corkscrew. Hebe was lost to a mine off Bari, Italy on 22 November 1943.

Friendly fire losses[edit]

As the Allied armies advanced following the invasion of Normandy, Britomart, Hussar, Jason and Salamander were assigned to the 1st Minesweeping Flotilla (1MF) clearing Axis minefields north of Normandy to open additional ports to supply the advance. On the afternoon of 27 August 1944, they were sweeping off Cap d'Antifer in preparation for the battleship Warspite and monitors Erebus and Roberts to engage Le Havre coastal artillery delaying the advance of Canadian troops.[4]

The headquarters officer assigning the minesweeping project to 1MF neglected to inform the Flag Officer British Assault Area (Rear‑Admiral Rivett‑Carnac), who was responsible for defending the invasion beaches from E-boats operating out of Le Havre. 1MF was observed on a southwesterly leg of the minesweeping operation and assumed to be German ships proceeding to attack Allied shipping off the invasion beaches. The Admiral's staff requested No. 263 Squadron RAF and No. 266 Squadron RAF to attack the presumed enemy ships. The squadrons responded with 16 Typhoons armed with 20 mm cannon and High Explosive "60 lb" RP-3 unguided rockets. RAF pilots identified 1MF as probably friendly shipping, but upon questioning their orders were told the Royal Navy had no ships in the area.[4]

In a well-executed attack out of the sun at 13:30, the Typhoons sank Britomart (Lt. Cdr. Nash, MBE, RNR) and Hussar (Lt.Cdr. A. J. Galvin, DSC, RNR); and Salamander was damaged so far beyond economical repair she was written off as a constructive total loss. Eighty-six British sailors were killed and 124 more were injured. 1MF identified the Typhoons as friendly, and poor visibility into the sun prevented early recognition of the impending "friendly fire". Jason established radio contact to terminate the attack.[4]

Ships in class[edit]

Reciprocating group[edit]

Turbine group[edit]

References[edit]

  • British and Empire Warships of the Second World War, H. T. Lenton, Greenhill Books, ISBN 1-85367-277-7
  • Warships of World War II, by H. T. Lenton & J. J. Colledge, Ian Allen Ltd, ISBN 0-7110-0202-9

External links[edit]