Alexander Macomb was laid down on 18 February 1942, under a Maritime Commission (MARCOM) contract, MCE hull 36, by the Bethlehem-Fairfield Shipyard, Baltimore, Maryland, and was launched on 6 May 1942.

[4] The Alexander Macomb sailed from New York City, where she loaded her cargo of 9,000 LT (9,100 t) of tanks, aircraft, and explosives destined for the Soviet Union, to join Convoy BX 27 for Halifax, on her maiden voyage.

[5] On the evening of 3 July 1942, sailing in heavy fog and with the fear of colliding with other ships in the convoy, Alexander Macomb fell behind.

At 12:30, on 4 July, with the rear of the convoy and her escorts in sight, Alexander Macomb was struck between the #4 and #5 holds by a torpedo from German submarine U-215, at 41°48′N 66°35′W / 41.800°N 66.583°W / 41.800; -66.583, causing her cargo of explosives to ignite and burst into flames.

The wreck of Alexander Macomb was discovered in October 1964, by the Risdon Beazley company salvage ship Droxford at position 41°48′N 66°35′W / 41.800°N 66.583°W / 41.800; -66.583.