HMS Chaser (D32)

HMS Chaser (D32/R306/A727) was an American-built Attacker-class escort carrier that served with the Royal Navy during the Second World War.

HMS Chaser in 1945
History
United States
Name:	Mormacgulf Mormacdove Breton
Namesake:	Moore-McCormack Lines, Inc. Breton Sound, Louisiana
Operator:	Moore-McCormack Lines, Inc. (intended)
Ordered:	as a C3-S-A1 hull MC-162[1]
Awarded:	9 September 1940
Builder:	Ingalls Shipbuilding, Pascagoula, Mississippi
Cost:	$7,412,192
Yard number:	295
Way number:	3
Laid down:	28 June 1941
Launched:	19 June 1942
Acquired:	27 March 1943
Renamed:	Breton, 26 December 1941
Reclassified:	ACV, 20 Aug 1942 CVE, 15 July 1943
Identification:	Hull symbol: AVG-10 ACV-10 CVE-10
Fate:	Transferred to the Royal Navy, 9 April 1943
United Kingdom
Name:	Chaser
Namesake:	One that chases or purses another
Acquired:	9 April 1943
Commissioned:	9 April 1943
Identification:	Pennant number: D32 R306 A727
Fate:	Returned to USN, 12 May 1946
United States
Name:	CVE-10
Acquired:	12 May 1946
Stricken:	3 August 1946
Fate:	Sold for merchant use, 20 Dec 1946
General characteristics
Class and type:	Bogue-class escort carrier (USA) Attacker-class escort carrier (UK)
Displacement:	8,390 long tons (8,520 t) (standard) 13,980 long tons (14,200 t) (full load)
Length:	465 ft (142 m) (wl) 495 ft 8 in (151.08 m) (oa) 440 ft (130 m) (fd)
Beam:	69 ft 6 in (21.18 m) wl 82 ft (25 m) (fd) 111 ft 6 in (33.99 m) (extreme width)
Draught:	23 ft 3 in (7.09 m) (mean) 26 ft (7.9 m) (max)
Installed power:	2 × Foster-Wheeler 285 psi (1,970 kPa) boilers 8,500 shp (6,300 kW)
Propulsion:	1 × Allis-Chalmers steam turbine 1 × Screw
Speed:	18 kn (33 km/h; 21 mph)
Complement:	646 officers and enlisted
Armament:	2 × 4 in (102 mm)/50 caliber MK 9 guns 4 × twin 40 mm (1.57 in) Bofors anti-aircraft guns (AA) (4×2) 8 × twin 20 mm (0.79 in) Oerlikon AA cannons 10 × single 20 mm Oerlikon AA cannons
Aircraft carried:	24
Aviation facilities:	1 × hydraulic catapult 2 × elevators
Service record
Operations:	Battle of the Atlantic, Arctic convoys (1943–45)
Victories:	Sank U-472, U-366, U-973 (1944)

Acquired by the United States Navy for conversion to a Bogue-class escort carrier; she was transferred to the Royal Navy and commissioned as Chaser on 9 April 1943, under the Lend-Lease agreement. She spent most of her career escorting convoys in Arctic, she transferred to the British Pacific Fleet in March 1945.

Construction

Chaser was laid down on 28 June 1941, under a Maritime Commission contract, MC hull 162, by Ingalls Shipbuilding, in Pascagoula, Mississippi, as Mormacgulf. Her name was changed to Mormacdove on 5 December 1941.[1] She was launched on 19 June 1942, sponsored by Mrs. Eugene T. Oates. After she was acquired by the US Navy, she was renamed Breton and designated AVG-10. On 20 August 1942, she was reclassified ACV-10. On 9 April, she was again reclassified, now CVE-10, and transferred to the Royal Navy under the Lend-Lease program and commissioned as HMS Chaser.[2]

Design and description

There were eleven Attacker-class in service with the Royal Navy during the Second World War. They were built between 1941 and 1942, by Seattle-Tacoma Shipbuilding Corporation, Ingalls Shipbuilding, and Western Pipe & Steel shipyards in the United States.[3]

The ship had complement of 646 men, who lived in crew accommodation that was significantly different from the arrangements that were normal for the Royal Navy at the time. The separate messes no longer had to prepare their own food, as everything was cooked in the galley and served cafeteria style in a central dining area. They were also equipped with a modern laundry and a barber shop. The traditional hammocks were replaced by three-tier bunk-beds, 18 to a cabin, which were hinged and could be tied up to provide extra space when not in use.[4]

Chaser had an overall length of 495 ft 8 in (151.08 m), a beam of 69 ft 6 in (21.18 m) and a draught of 24 ft 8 in (7.52 m). She displaced 14,170 long tons (14,400 t) at full load. Power was provided by two boilers feeding steam to a turbine driving one shaft, giving 8,500 bhp (6,300 kW), which could propel the ship at 18 kn (33 km/h; 21 mph).[5]

She had the operating capacity for up to 24 aircraft, which could be a mixture of anti-submarine and fighter aircraft; the British Hawker Sea Hurricane and Supermarine Seafire naval fighters, Fairey Swordfish torpedo bomber or the American-supplied Grumman Martlet and Vought F4U Corsair fighters or Grumman Avenger torpedo bomber could be carried.[6] The exact composition of the embarked squadrons depended upon the mission. Some squadrons were composite squadrons for convoy defence and would be equipped with both anti-submarine and fighter aircraft,[7] while other squadrons working in a strike carrier role would only be equipped with fighter aircraft.[8] Aircraft facilities were a small combined bridge–flight control on the starboard side and above the 450 ft × 120 ft (137 m × 37 m) flight deck,[9] two aircraft lifts 42 ft × 34 ft (13 m × 10 m), and nine arrestor wires. Aircraft could be housed in the 260 ft × 62 ft (79 m × 19 m) hangar below the flight deck.[6] When employed as an aircraft transport she could carry 90 aircraft.[10]

A typical twin 40 mm Bofors anti-aircraft gun mounting on the Attacker-class.

The ships armament concentrated on anti-aircraft (AA) defence and consisted of eight 40 mm (1.57 in) Bofors guns in twin mounts and ten 20 mm (0.79 in) Oerlikon cannons in single and eight in twin mounts.[6] In addition, she had two 4 inch (102 mm)/50 caliber Mk 9 guns.[10]

Chaser was designed to accompany other ships forming the escort for convoys.[11] The anti-submarine aircraft employed were initially the Fairey Swordfish and later the Grumman Avenger, which could be armed with torpedoes, depth charges, 250 lb (110 kg) bombs or RP-3 rocket projectiles.[12] As well as carrying out their own attacks on U-boats, these aircraft identified their locations for the convoy's escorts to mount an attack.[13] Typically anti-submarine patrols would be flown between dawn and dusk. One aircraft would fly about 10 mi (16 km) ahead of the convoy, while another patrolled astern. Patrols would last between two and three hours, using both radar and visual observation in their search for U-boats.[14]

Chaser also had a secondary role, providing oil and provisions for her accompanying destroyers. This could be a lengthy process and was done on the move. It took 40 minutes from firing a line across to the destroyer to start pumping oil, while it took another two hours to pump 98 tons of oil and a further 35 minutes to disconnect the hose pipe and secure the equipment.[15]

Service history

After workup in the Chesapeake Bay area, Chaser embarked 845 Squadron, which had been formed in the US, on 23 June 1943, for passage across the Atlantic. She crossed the Atlantic in company with Convoy HX 245, arriving at the Clyde on 6 July 1943.[16][17]

On 7 July 1943, there was an explosion in Chaser's boiler room. She was repaired at Rosyth Dockyard. On 29 October, with her repairs completed, she returned to the Clyde, where she was allocated to the Western Approaches Command. She embarked 835 Squadron equipped with Fairey Swordfish and Sea Hurricanes for workup. On 29 November, Chaser returned to the Clyde for further defect rectification. These repairs would continue for the remainder of the year.[16][17] Upon the return to active duty she was attached to the Home Fleet for convoy duty on the Russian convoy route, embarking 816 Squadrons, equipped with Swordfish and Grumman Wildcats, and sailed for Scapa Flow.[17]

Arctic duty

On 22 January 1944, Chaser joined Convoy JW 57, which had left Loch Ewe the previous day, for escort to the Kola Inlet. She was the first escort carrier assigned to provide protection for large convoys as they steamed to Russia.[18] Chaser's Wildcats helped to drive off German aircraft shadowing the convoy, while her Swordfish made several unsuccessful attacks against German submarines.[19] On 24 February, one of Chaser' Swordfishes spotted the submarine U-713 on the surface and called up the destroyer Keppel which sank the U-boat with depth charges.[20] A second submarine U-601 was sunk by a shore based flying boat, while one escorting destroyer, Mahratta was sunk by a U-boat. None of the 43 merchant ships comprising the convoy was hit by the 14 U-boats deployed in two patrol lines against the convoy.[19][21]

Chaser joined the return convoy, RA 57 of 33 merchant ships, on 2 March.[22] On 4 March, one of Chaser's Swordfish caught U-472 on the surface. U-472 was unable to defend itself as its anti-aircraft guns were iced up, and the Swordfish attacked with bombs and rockets, damaging the submarine, and then called up the destroyer Onslaught which finished off the submarine with gunfire.[23][24][25] The next day, a Swordfish from Chaser attacked and sunk U-366 with rockets, at 72°10′N 14°44′E in the Arctic, northwest of Hammerfest, Norway.[23][25][26] On 6 March, radio signals from a submarine were detected by HF/DF and a Swordfish was sent to investigate. The Swordfish spotted the submarine and attacked with rockets, sinking U973 at 70°04′N 5°48′E in the Norwegian Sea, northwest of Narvik, Norway.[25][26] One merchant ship was sunk.[22]

After returning to Loch Ewe on 10 March, Chaser dragged her anchor and ran aground on 13 March, being towed off the next day. She had her hull repaired and was refitted at Rosyth and was then modified for service as a ferry carrier with the Pacific Fleet at Belfast.[16][27]

Pacific duty

On 14 February 1945, Chaser left Britain on the first part of the journey to join the British Pacific Fleet, arriving in Sydney in May 1945,[27] where she was attached to the 30th Aircraft Carrier Squadron.[28] She was designated as a replenishment carrier, tasked with ferrying replacement aircraft to the forward areas where they could be transferred to the operational carriers.[27] Chaser ferried aircraft to support British Pacific fleet operations during the invasion of Okinawa and operations off Japan in July–August 1945.[27] Owing to a shortage to dedicated tankers, Chaser was also used to refuel other ships.[27]

Following the Japanese surrender in August 1945, she transported Allied prisoners of war homeward.[2]

Decommissioning

The escort carrier was returned to the United States Navy at Norfolk, Virginia on 12 May 1946,[27][2] and the ship was struck from the US Navy list on 3 August 1946.[2] She was sold to the Waterman Steamship Co. on 20 December 1946 and later resold to the Netherlands.[2]

Merchant service

She was renamed Aagtekerk in civilian service and was later renamed E Yung. The ship foundered on 4 December 1972, and was salvaged and then scrapped in Taiwan.[16]

FAA squadrons

Fleet Air Arm Squadrons stationed on Chaser[29]

Squadron	Dates	Aircraft type
835	November 1943 – December 1943	Fairey Swordfish Mks.II/Hawker Sea Hurricane
816	April 1943 - September 1943	Fairey Swordfish Mks.II/Grumman Wildcat Mk.V
899	August 1943 - October 1943	Supermarine Seafire L.III

References

1. MARCOM.
2. DANFS - Breton.
3. Cocker 2008, p. 79.
4. Poolman 1972, pp. 74-75.
5. Cocker 2008, pp. 80-81.
6. Cocker 2008, p. 80.
7. Poolman 1972, p. 98.
8. Morison 2002, p. 342.
9. Poolman 1972, p. 57.
10. Hobbs 1996, p. 73.
11. Poolman 1972, p. 155.
12. Poolman 1972, p. 135.
13. Cocker 2008, p. 147.
14. Poolman 1972, p. 79.
15. Poolman 1972, p. 102-103.
16. Hobbs 1996, p. 74.
17. Hobbs 2013, p. 141.
18. Ruegg & Hague 1993, p. 61.
19. Roskill 1960, pp. 270–271.
20. Kemp 1997, pp. 171–172.
21. Ruegg & Hague 1993, pp. 61–62.
22. Ruegg & Hague 1993, p. 62.
23. Blair 2000, p. 515.
24. Kemp 1997, pp. 173–174.
25. Helgason.
26. Kemp 1997, p. 174.
27. Hobbs 2013, p. 142.
28. Hobbs 2017, pp. 166, 253.
29. Sturtivant & Ballance 1994, p. 395.

Bibliography

• Blair, Clay (2000). Hitler's U-Boat War: The Hunted 1942–1945. New York: Modern Library. ISBN 0-679-64033-9.
• "Breton". DANFS. Navy Department, Naval History and Heritage Command. Retrieved 17 December 2020. This article incorporates text from this source, which is in the public domain.
• Cocker, Maurice (2008). Aircraft-Carrying Ships of the Royal Navy. Stroud, Gloucestershire: The History Press. ISBN 978-0-7524-4633-2.
• Helgason, Guðmundur. "HMS Chaser (D 32)". German U-boats of WWII - uboat.net. Retrieved 17 December 2020.
• Hobbs, David (1996). Aircraft Carriers of the Royal and Commonwealth Navies. London: Greenhill Books. ISBN 1-85367-252-1.
• Hobbs, David (2013). British Aircraft Carriers: Design, Development and Service Histories. Barnsley, UK: Seaforth Publishing. ISBN 978-1-84832-138-0.
• Hobbs, David (2017). The British Pacific Fleet: The Royal Navy's Most Powerful Strike Force. Barnsley, UK: Seaforth Publishing. ISBN 978-1-5267-0238-8.
• Kemp, Paul (1997). U-Boats Destroyed: German Submarine Losses in the World Wars. London: Arms & Armour Press. ISBN 1-85409-321-5.
• Morison, Samuel (2002). History of United States Naval Operations in World War II. Urbana, Illinois: University of Illinois Press. ISBN 978-0-252-07062-4.
• Poolman, Kenneth (1972). Escort Carrier 1941–1945. London: Ian Allan. ISBN 0-7110-0273-8.
• "Mormacgulf". United States Maritime Commission. Retrieved 17 December 2020.
• Roskill, S. W. (1960). The War at Sea 1939–1945: Volume III: The Offensive Part I: 1st June 1943 – 31st May 1944. London: Her Majesty's Stationery Office.
• Ruegg, Bob; Hague, Arnold (1993). Convoys to Russia 1941–1945. Kendal, UK: World Ship Society. ISBN 0-905617-66-5.
• Sturtivant, Ray; Ballance, Theo (1994). The Squadrons of the Fleet Air Arm. Tonbridge, Kent, UK: Air Britain (Historians) Ltd. ISBN 0-85130-223-8.