The success of the converted CVEs led to a fresh design being prepared 'from the keel up', using a mercantile design as a basis but tailoring it to meet OVE needs, rather than adapting a hull on the slipway. These adaptations were more concerned with ease of construction than any radical improvement in operational capability. In all, 50 units of the 'Casablanca' class (CVE.55104) were authorized late in 1942. Although the flight deck was short (500 ft/152.4 m by 108 ft/32.9 m), two lifts and a catapult were provided, and as there were two propeller shafts there was greater manoeuvrability than with one shaft. To speed up manufacture, triple-expansion steam machinery was chosen, but in other respects the 'Casablanca' design took the best of the 'Sangamon', 'Bogue' and 'Prince William' classes, and was a considerable success.
The USS St Lò (CVE.63) was laid down as the Chapm Bay (AVG.63) at Henry Kaiser's Vancouver shipyard in January 1943, but in April she was renamed Midway in honour of the recent battle, and entered service under that name in October 1943. The name was then allocated to a much bigger carrier, as it was considered too important for such a minor warship, and on 15 September 1944 CVE.63 became the USS St Lô. The little carrier had already made two ferry trips out to the Pacific and had supported the amphibious landings in Saipan, Eniwetok, Tinian and Morotai. In October 1944 she formed part of 'Taffy Three1, part of the vast armada which fought the Battle of Ley te Gulf, 'Taffy Three', the most northern group of escort carriers covering the amphibious landing, had already suffered a gruelling bombardmen from Japanese surface warships for the best part of 3 hours during the morning of 25 October 1944. After a lull of about 1 hour the kamikazes made a low-level attack, five Zeros coming in at low level before climbing rapidly to 1525m (5,000ft) and then diving straight onto the flight deck. One of a pair attacking the Fanshaw Bay suddenly switched to the St Lo, striking her flight deck aft. The two bombs slung underneath the Zero set off gasoline, bombs and ammunition in the hangar, and wrecked the ship.
The kamikaze hit at 10.53, and five minutes later a huge explosion devastated the carrier. She sank about 1 hour later, with 100 dead and many injured, the first American ship sunk by kamikaze attack.
Specification USS St Lò (CVE.63) Displacement: 7,800 tons standard, 10,400 tons full load Dimensions: length 156.13m (512ft 3 in) overall; beam 39,92 m (108 ft 0 in) over flight deck; draught 6.86 m (22 ft 6in) Machinery: 2-shaft vertical tripleexpansion delivering 6715 kW (9,000 ihp) Speed: 19 knots Armour: none Armament: one 127-mm (5-m) AA, eight twin 40-mm Bofors AA and 20 20-mm AA guns Aircraft: (October 1944) 17 Grumman F4F Wildcat fighters and 12 Grumman TBF Avenger torpedo-bombers Complement: 860 officers and enlisted