Crater-class cargo ship

The Crater-class cargo ship were converted EC2-S-C1 type, Liberty cargo ships, constructed by the United States Maritime Commission (USMC) for use by the US Navy during World War II. The designation 'EC2-S-C1': 'EC' for Emergency Cargo, '2' for a ship between 400 and 450 ft long (Load Waterline Length), 'S' for steam engines, and 'C1' for design C1.

The class was named for the lead ship of its type, USS Crater (AK-70), with most ships in the class being named for astronomical bodies. Its 65 hulls were among the largest US Navy cargo ship classes.

The ships were propelled by a reciprocating steam engine using a single screw with a power of 2500 hp shaft.

Notable incidents

 * USS Aludra (AK-72) 	Lost in action from Japanese torpedo on 23 June 1943 south of Makira island.
 * USS Deimos (AK-78) 	Damaged by torpedo, 23 June 1943, then abandoned and scuttled south of Makira island.