Marco Polo was a cargo ship built under a US Maritime Commission contract, by the North Carolina Shipbuilding Co., Wilmington, North Carolina. The ship was renamed Mount Hood on 10 November 1943; launched on 28 November 1943; sponsored by Mrs. A. J. Reynolds; acquired by the Navy on loan-charter basis on 28 January 1944; converted by the Norfolk Shipbuilding & Dry Dock Co., Norfolk, Virginia, and the Norfolk Navy Yard; and commissioned on 1 July 1944, Comdr. Harold A. Turner in command. Following an abbreviated fitting out and shakedown period in the Chesapeake Bay area, ammunition shipMount Hood reported for duty to ComServFor, Atlantic Fleet, on 5 August 1944. Assigned to carry cargo to the Pacific, she put into Norfolk, where her holds were loaded. On 21 August, as a unit of Task Group 29.6, she transited the Panama Canal on the 27th, and continued on, independently, via Finschafen, New Guinea. Mount Hood arrived at Seeadler Harbor, in Manus Island of the Admiralty Islands, on 22 September. Assigned to ComSoWesPac, she commenced dispensing ammunition and explosives to ships preparing for the Philippine offensive.
Disaster
At 08:30 on 10 November 1944, a party consisting ofcommunications officer, Lt. Lester H. Wallace, and 17 men left the ship and headed for shore. At 08:55, while walking on the beach, they saw a flash from the harbor, followed by two quick explosions. Scrambling into their boat, they headed back to the ship, only to turn around again shortly thereafter as "There was nothing but debris all around...". Mount Hood, anchored in about of water, had exploded with an estimated of ordnance material on board. The initial explosion caused flame and smoke to shoot up from amidships to more than masthead height. Within seconds, the bulk of her cargo detonated with a more intense explosion. Mushrooming smoke rose to, obscuring the ship and the surrounding area for a radius of approximately. Mount Hoods former position was revealed by a trench in the ocean floor long, wide, and deep. The largest remaining piece of the hull was found in the trench and measured no bigger than. No other remains of Mount Hood were found except fragments of metal which had struck other ships in the harbor and a few tattered pages of a signal notebook found floating in the water several hundred yards away. No human remains were recovered of the 350 men aboard Mount Hood or small boats loading alongside at the time of the explosion. The only survivors from the Mount Hood crew were Lt. Wallace and the 17 enlisted men who had left the ship a short time before the explosion. Two of the crew were being transferred to the base brig for trial by court martial; and the remainder of the party were visiting the base chaplain or picking up mail at the base post office. Charges against the prisoners were dropped following the explosion. The concussion and metal fragments hurled from the ship caused casualties and damage to other ships and small craft within. The repair ship, which was broadside-on to the blast, was the most seriously damaged. All personnel topside on Mindanao were killed outright, and dozens of men were killed or wounded below decks as numerous heavy fragments from Mount Hood penetrated the side plating. Eighty-two of Mindanaos crew died. 22 small boats and landing craft were sunk, destroyed, or damaged beyond repair, while damage to other vessels required more than 100,000 man-hours to repair; a further 371 sailors from ships in the harbor were injured. A board convened to examine evidence relating to the disaster was unable to ascertain the exact cause. After only a little over four months' service, Mount Hood was struck from the Naval Register on 11 December 1944.
The following ships were damaged by the explosion of Mount Hood:
In addition to the above ships, nine medium landing craft and a pontoon barge moored alongside Mount Hood were also destroyed, and 13 small boats or landing craft were sunk or damaged beyond repair.
