USS Sangamon (AVG/ACV/CVE-26), was a US Navy escort carrier of World War II. Originally built as Esso Trenton, one of twelve tankers built by a joint Navy-Maritime Commission design. This design was later duplicated and designated a T3-S2-A1 oiler. She was acquired by the Navy in October 1940, and renamed Sangamon, for use as a fleet oiler. In 1942, she converted into the lead ship of the . Originally classified as an "Aircraft Escort Vessel", and designated AVG-26, in February 1942, she was reclassified as an "Auxiliary Aircraft Carrier", ACV-26, in August 1942. When the US Navy had another major reclassification on 15 July 1943, Sangamon was again reclassified, this time as an "Escort Carrier", CVE-26. She was named after the Sangamon River, in Illinois.

Construction Esso Trenton was laid down by the Federal Shipbuilding and Dry Dock Company, in Kearny, New Jersey, MC hull 7, on 13 March 1939, and launched on 4 November 1939.

Civilian service Esso Trenton was delivered on 14 December 1939, to her new owner and operator, Standard Oil of New Jersey, for runs from Gulf Coast ports to the East Coast.

Service history Nearly a year after being put into service, Esso Trenton was acquired by the United States Navy, on 22 October 1940, and renamed Sangamon. She was classified, AO-28, one of 35 fleet oilers, and commissioned on 23 October 1940.

Fleet oiler service After service off the West Coast and in Hawaiian waters, Sangamon shifted to the Atlantic Fleet, in the spring of 1941, and through the Neutrality Patrol period. She once again carried fuel from the Gulf Coast oil ports to bases on the East Coast, and now, Canada and Iceland. On 7 December 1941, she was at Naval Station Argentia, Newfoundland, offloading her cargo. Within the week, she started south again to renew her schedule on a tighter time frame.

Conversion to escort carrier In early 1942, she was selected for conversion to an "Aircraft Escort Vessel" (AVG). On 11 February, she arrived in Newport News, Virginia. Three days later, she was reclassified AVG-26; and on 25 February, she was decommissioned and conversion was begun at the Newport News Shipbuilding and Drydock Co.

During the spring and summer, the need for auxiliary carriers, later called escort carriers, increased. Work on Sangamon, three other Cimarron-class oilers, and 20 C-3 merchant hulls was continued and sped up. In August, Sangamon, the first of her class was ready. Her conversion had added a flight deck that was long and wide, two center mounted elevators, a hangar deck, an aircraft catapult, sonar gear, aircraft ordnance magazines, workshops, and stowage space for aviation spares. Her accommodations had been enlarged to house her increased complement and embarked aviation personnel. Her /51 caliber guns, had been reduced to two and mounted at the fantail, she retained her four twin mount Bofors guns, and increased her Oerlikon cannons to twelve single mounts, from four twin mounts, to increase her anti-aircraft defense. On 20 August, she was again reclassified, as an "Auxiliary Aircraft Carrier", ACV-26; and five days later, she was recommissioned.

Sangamon and her three sister T3 conversions were considered very successful escort carrier designs, larger and more stable than the smaller C3-derived ; additionally, they retained substantial oil bunkerage, useful in refueling destroyers in company. The late-war purpose-built escort carriers were derived from the Sangamons.

WWII service history 1942

Shakedown in Chesapeake Bay and off Bermuda followed a return to the yard for repair and improvements to her ventilation system. On 25 October she sailed east with Task Force 34 (TF 34) to provide air cover for Operation Torch, the invasion of North Africa. Assigned to the Northern Support Force, she arrived off Port Lyautey, on 8 November. Prior to and during the landings, and subsequent action, her air group, Composite Squadron 26 (VC-26) flew combat air patrol (CAP), anti-submarine patrol (ASP), and ground support missions. At mid-month, she got underway to return to Norfolk, where, after repairs, she sailed for Panama and the Pacific.

1943 By mid-January 1943, Sangamon had arrived at Éfaté, New Hebrides. As a unit of Carrier Division 22 (CarDiv 22), she operated in the New Caledonia—New Hebrides—Solomon Islands area for the next eight months. With her sister ships, and , she provided protection for resupply convoys en route to Guadalcanal and for the assault forces moving on the Russell Islands.

Redesignated CVE-26 on 15 July 1943, Sangamon shifted her base of operations from Efate, to Espiritu Santo, in August, and in September, she returned to the United States for an overhaul at Mare Island. There she received more modern equipment for her flight deck and a combat information center.

On 19 October, she departed San Diego, with VC-37 embarked and sailed for Espiritu Santo. She got underway from the latter on 13 November, rendezvoused with Task Force 53 the next day, and on 20 October, arrived in the Gilberts to support the assault on Tarawa Atoll. During the first two days of this operation, her planes struck enemy positions on the island. Then, through 6 December, they were sent out on CAP and ASP missions to protect the escort carrier group and the target area.

1944

Sangamon set course to return to San Diego. In early January 1944, she trained off southern California, and on 13 January, sailed west. Steaming via Pearl Harbor, she pushed on toward her next amphibious operation, the assault on Kwajalein in the Marshall Islands. For this operation Sangamon was part of a task group with two other carriers, and , with Sangamon serving as the flagship.

At 16:51, on 25 January, during routine flight operations, an F6F-3 Hellcat (Bureau number 40845) from fighter squadron VF-37 failed to hook a wire on landing, broke through the barriers, and crashed into parked planes on the forward flight deck. Its belly tank, torn loose, skidded forward, spewing flaming fuel. Fire soon spread among the planes. It raged along the flight deck and flames beat up over the bridge, making ship control extremely difficult. The carrier was turned out of the wind, so that the fire could be fought. By 16:59, it was under control. Seven of the crew died in those eight minutes. Seven others were seriously injured, and of the 15 who jumped over the side to escape the flames, 13 were picked up, two were missing. The accident also destroyed four Hellcats and a SBD Dauntless was knocked overboard. Later the same day, a TBM Avenger crashed into parked aircraft while landing, damaging beyond repair three SBD Dauntless' and another TBM, fortunately without serious injuries.

The next day, 26 January, Sangamon collided with Suwannee. This was at low speed; no personnel were injured on either ship and Suwannee bore the brunt of the damage, with of her flight deck buckled. However the damage was not significant enough to prevent either carrier from continuing air operations.

Temporary repairs were made at sea, and from 31 January, to mid-February, Sangamon supported the assault and occupation of Kwajalein. She then moved on to Enewetak, where her planes covered the landing forces from 17 to 24 February. On the latter date, she departed the Marshalls, and headed back to Pearl Harbor, to complete repairs.

On 15 March, Sangamon got underway again. Departing Hawaii, she rendezvoused with Task Group 50.15 (TG 50.15), the fast carrier force support group, on 26 March. For the remainder of the month, and into April, she escorted that group as it operated north of the Admiralty Islands, to refuel and resupply the fast carrier force, after it had conducted strikes on the Palaus. In early April, Sangamon retired to Espiritu Santo, and at mid-month, sailed for New Guinea. Briefly attached to the 7th Fleet, she covered the landing at Aitape, from 22 to 24 April; retired to Manus Island for two days, then returned to the Aitape area where she conducted patrols until 5 May.

Sangamon then returned to Espiritu Santo, where she departed on 19 May. Rehearsals for the Marianas campaign followed, and on 2 June, she sailed for the Marshalls. Rendezvousing with TF 53 en route, she covered that force to Kwajalein, then to the Mariana Islands. From 17 to 20 June, she guarded the force as it steamed to the east of Saipan, as a backup force for TF 52, which was then engaged in the assault on and the occupation of the island.

After the Battle of the Philippine Sea, Sangamon was detached from TF 53. On 21 June, she joined TF 52, and into July, she conducted operations in support of the occupation of Saipan. On 4 July, she steamed for Eniwetok; arrived on 7 July; and sortied again on 10 July. From 13 July to 1 August, she covered the bombardment groups engaged in the capture of Guam. On 4 August, she returned to Eniwetok, where on 9 August she proceeded to Manus Island, where she was anchored for almost a month.

On 9 September, Sangamon departed Seeadler Harbor and steamed for Morotai. There, from 15 to 27 September, she again covered Allied assault forces. After the initial waves had landed, her planes shifted from combat support to bombing and strafing missions to destroy Japanese airfields on nearby Halmahera.

Sangamon again anchored in Seeadler Harbor, on 1 October. Twelve days later, she sortied with TG 77.4, the escort carrier group of the Leyte invasion force. That group, composed of 18 escort carriers, was broken down into Task Units 77.4.1, 77.4.2, and 77.4.3 (TU 77.4.1, 77.4.2, and 77.4.3), and referred to as "Taffy 1, 2, and 3", respectively. During the operation, they would steam to the east of Leyte Gulf: Taffy 1, including Sangamon, was off northern Mindanao; Taffy 2 off the entrance to Leyte Gulf; and Taffy 3 off Samar.

Prior to the 20 October landings on Leyte, Sangamon launched regular flights in support of the advance units of the invasion force and sent strikes against Leyte and Visayan Islands airfields. On 20 October, her planes covered the landing forces and the ships in the transport areas. That day, she also came under enemy air attack and took a hit at the main deck level. The bomb, dropped by an A6M5 Zero, tore a section of plating loose, then fell into the sea and exploded some away from the carrier.

Enemy airfields again became Sangamons primary targets in the days immediately following the landings. On 24 October, however, her planes fought off waves of Japanese aircraft over the landing area. Early on 25 October, two flights took off: one toward the Mindanao Sea to locate and finish off Japanese survivors of the Battle of Surigao Strait, the other toward Leyte, for CAP missions. About an hour later, Sangamon received word that Taffy 3, to the north, had been attacked by the Japanese Center Force which had transited San Bernardino Strait during the night.

Battle off Samar

Within a half-hour, Sangamons CAP flight had been diverted to Samar, and she had launched another smaller group to further aid the attacked unit. Soon thereafter, at about 07:40, as Taffy 1 planes were being recovered, rearmed, and launched, the unit became the target of the first strike of the Kamikaze unit.

took the first hit, and as her flight and hangar decks blazed, was attacked. Antiaircraft fire from Suwannee scored on the planes, which then dived toward Sangamon. A 5-inch shell from Suwannee finished one plane only from Sangamon. By 07:55, had joined the fight, and, as Santees crew brought her fires under control, sent a torpedo into that luckless CVE. Minutes later, Suwannee was hit by a "Zero" forward of the after elevator.