CAM ships were
They were equipped with a rocket-propelled catapult launching a single Hawker Hurricane, dubbed a "Hurricat" or "Catafighter" to destroy or drive away an attacking bomber. Normally the Hurricane fighter would be lost when the pilot then bailed out or ditched in the ocean near the convoy.[Note 1] CAM ships continued to carry their normal cargoes after conversion.
The concept was developed and tested by the five
To counter this threat, the
The Admiralty had already experimented with this system. They ordered 50 rocket-propelled
The pilots for these aircraft were drawn from the Royal Air Force (RAF). The RAF formed the Merchant Ship Fighter Unit (MSFU) on 5 May 1941 in RAF Speke by the River Mersey in Liverpool. Wing Commander E.S. Moulton-Barrett commanded the unit providing training for volunteer pilots, fighter direction officers (FDOs), and airmen. After training, MSFU crews were posted to Liverpool, Glasgow, or Avonmouth where they assisted in loading their Hurricanes onto the catapults. Each team consisted of one pilot for Atlantic runs (or two pilots for voyages to Russia, Gibraltar, or the Mediterranean Sea), with one fitter, one rigger, one radio-telephone operator, one FDO, and a seaman torpedoman who worked on the catapult as an electrician.
MSFU crews signed ship's articles as civilian crew members under the authority of the civilian
The first four or five ships were taken into Royal Navy service as "auxiliary fighter catapult ships", and later conversions were officially named CAMs and crewed by merchant sailors. The first CAM ship, Michael E, was sponsored by the Royal Navy while the RAF MSFUs were working up. After a trial launch off Belfast, Michael E sailed with convoy OB 327 on 28 May 1941. She was sunk by U-108 on 2 June. The first RAF trial CAM launch was from Empire Rainbow, at Greenock on the River Clyde on 31 May 1941; the Hurricane landed at Abbotsinch. Six CAM ships joined convoys in June 1941. When a CAM ship arrived at its destination, the pilot usually launched and landed at a nearby airfield to get in as much flight time as possible before his return trip. Pilots were rotated out of CAM assignments after two round-trip voyages to avoid the deterioration of flying skills from the lack of flying time during the assignment.
CAM sailings were initially limited to North American convoys with aircraft maintenance performed by the
Eight CAM ships were requisitioned from private owners, two of which were sunk:
- Eastern City
- Michael E (sunk)
- Primrose Hill (sunk).
27 CAM ships were Ministry of War Transport owned Empire ships, ten of which were sunk:
- Empire Burton(sunk)
- Empire Clive
- Empire Darwin
- Empire Day
- Empire Dell(sunk)
- Empire Eve(sunk)
- Empire Faith
- Empire Flame
- Empire Foam
- Empire Franklin
- Empire Gale
- Empire Heath
- Empire Hudson (sunk)
- Empire Lawrence (sunk)
- Empire Moon
- Empire Morn
- Empire Ocean
- Empire Rainbow (sunk)
- Empire Ray
- Empire Rowan (sunk)
- Empire Shackleton (sunk)
- Empire Spray
- Empire Spring (sunk)
- Empire Stanley
- Empire Sun
- Empire Tide
- Empire Wave (sunk).
- The trolley receiving bar was removed at dawn.
- The airmen started the aircraft and warmed up the engine at intervals.
- The pilot climbed into the aircraft when enemy aircraft were reported.
- The ship hoisted the international flag code F when the decision was made to launch. (CAM ships were usually stationed at the head of the outboard port column of a convoy so they could manoeuvre into the wind for launch.)
- An airman removed the pins, showed them to the pilot, and took them to the Catapult Duty Officer (CDO).
- The pilot applied 30 degree flaps and 1/3 right rudder.
- The CDO raised a blue flag above his head to inform the ship's master of his readiness to launch.
- The ship's master manoeuvred the ship into the wind and raised a blue flag above his head to authorise the launch. (The ship's master stood on the starboard bridge wing to avoid the catapult rocket blast which sometimes damaged the portside of the bridge.)
- The CDO waved his blue flag indicating he was ready to launch upon a signal from the pilot.
- The pilot opened full throttle, tightened the throttle friction nut, pressed his head back into the head-rest, pressed his right elbow tightly against his hip, and lowered his left hand as a signal to launch.
- The CDO counted to three, waited for the bow to rise from the trough of a swell, and moved the switch to fire the catapult rockets.
CAM combat launches
|18 July 1941||HMS Maplin||Lt
|Focke-Wulf Fw 200 Condor was shot down by a ship's anti-aircraft guns, just as the Hurricane pilot was about to attack. Everett flew to Northern Ireland and landed at RAF St Angelo.|
|3 Aug 1941||HMS Maplin / OG 17||Lt
|Focke-Wulf Fw 200 Condor shot down; pilot recovered by a destroyer|
|1 Nov 1941||
SS Empire Foam / HX 156
|Focke-Wulf Fw 200 chased off; pilot recovered by HMS Broke|
|26 Apr 1942||SS Empire Morn / QP 12||FO JB Kendal|
|26 May 1942||
SS Empire Lawrence / PQ 16
|Two Heinkel He 111s shot down; Hurricane shot down, pilot wounded and recovered by HMS Volunteer|
|14 Jun 1942||SS Empire Moon / HG 84||PO Sanders||Focke-Wulf Fw 200 chased off; pilot recovered by HMS Stork|
|18 Sep 1942||SS Empire Morn||FO AH Burr||Two Heinkel He 111s destroyed; pilot flew to the Russian Keg Ostrov aerodrome|
|1 Nov 1942||SS Empire Heath / HG 91||FO N Taylor||Focke-Wulf Fw 200 shot down; pilot nearly drowned before recovery|
|28 Jul 1943||SS Empire Darwin / SL 133||FO JA Stewart||Focke-Wulf Fw 200 destroyed; pilot recovered by HMS Leith|
|28 Jul 1943||MV Empire Tide / SL 133||FO PJR Flynn||Focke-Wulf Fw 200 destroyed; pilot recovered by HMS Enchantress|
In total, there were nine combat launches. Nine German aircraft were destroyed (four Condors, four Heinkel 111s and a Junkers 88), one damaged and three chased away. Eight Hurricanes were ditched and only one pilot lost.
As adequate numbers of escort carriers became available, CAM sailings on North American and Arctic Russian convoys were discontinued in August 1942. The aircraft maintenance unit was withdrawn from Archangelsk in September 1942. Catapults were removed from 10 of the 26 surviving CAM ships while the remaining 16 continued to sail with the Mediterranean and Freetown convoys. Headquarters RAF Fighter Command ordered all MSFUs to be disbanded commencing 8 June 1943. The combat launches from homeward bound convoy SL 133 were from the last two operational CAM ships to sail; the last MSFU was disbanded on 7 September 1943. Twelve of the 35 CAM ships had been sunk while sailing on 170 round trip voyages. Two more ships, Cape Clear and City of Johannesburg, were briefly fitted with dummy catapults and aircraft for deception purposes in late 1941.
- Merchant aircraft carrier
- Fighter catapult armed auxiliary ship
- Brodie landing system
- Aviation-capable naval vessel
- ^ Although on several occasoions the pilot was close enough to an airfield to land there instead
- Barker, Ralph (2019). HURRICATS : the incredible true story of britain's 'kamikaze' pilots of world war two. [Place of publication not identified]: SILVERTAIL Books. OCLC 1099529804.
- Hague, Arnold (2000). The Allied Convoy System 1939–1945. Naval Institute Press. ISBN 1-55750-019-3.
- Mitchell, W H, and Sawyer, L A (1990). The Empire Ships. London, New York, Hamburg, Hong Kong: Lloyd's of London Press Ltd. ISBN 1-85044-275-4.
- Pauly, John; Truebe, Carl E.; Wilde, Doug & Wilterding, John H. (2012). "Question 14/48: Catapult Armed Merchant Ships". Warship International. XLIX (2): 160–170. ISSN 0043-0374.
- Wise, James E. Jr. (1974). "Catapult Off – Parachute Back". United States Naval Institute Proceedings.