below the flight deck. Her armament consisted of three single-mounted 4 inch dual purpose anti-aircraft guns—two forward and one aft—and fifteen 20 mm cannon on single or twin mounts. She had the capacity for fifteen aircraft, which could be a mixture of Grumman Martlet or Hawker Sea Hurricane fighter aircraft and Fairey Swordfish anti-submarine aircraft. Service history On 18 April 1942, Avenger started flight deck landing training with four Fairey Swordfish aircraft of 816 Naval Air Squadron, Fleet Air Arm. The exercise had to be curtailed when her engines broke down. Repaired by 30 April 1942, she joined the escort for convoy AT 15 to cross the Atlantic to Britain. During the crossing the Swordfish of 816 Squadron provided anti-submarine patrols. On 4 May, two aircraft lost the convoy in heavy weather and requested a homing beacon from Avenger. She was unable to help, not having the correct equipment, and both aircraft and crews were reported missing. When Avenger arrived in Britain the Fleet Air Arm had a shortage of Martlet fighter aircraft, so a small number of Royal Air Force Hawker Hurricanes were converted into Sea Hurricanes. Avenger was chosen to test their deck landing ability on escort carriers. The tests, flown by Eric "Winkle" Brown, were successful, and the Sea Hurricane equipped 802 Naval Air Squadron and 882 Naval Air Squadron, with 12 aircraft assigned to Avenger. They were joined by three Fairey Swordfish and five crews from 825 Naval Air Squadron. Convoy PQ 18 On 3 September 1942, Avenger, under the command of ex-Swordfish pilot Commander Anthony Paul Colthust, left Britain for Iceland to take part in Convoy PQ 18. The weather was cold, and in heavy seas one of her Sea Hurricanes broke its restraints and was lost over the side. The ship was located at sea by a Luftwaffe Focke-Wulf Condor, and shortly after arriving in Iceland, Avenger was subjected to a bombing attack by another Condor. Both of the bombs it dropped missed the ship, but two houses ashore were demolished. In their determination for PQ 18 to be a success, the Royal Navy created the largest escort force ever assembled for an Arctic convoy up until that time. Under command of Rear-Admiral Robert Burnett, the force included Avenger—the only aircraft carrier—which was joined by the anti-aircraft cruiser and 16 fleet destroyers, plus the normal complement of close support sloops, corvettes, and minelayers. Avenger