After taking on 7,187 long tons (7,302 t) of Army materiel, she departed for Bordeaux on 4 October in a convoy escorted by cruiser Denver.
On the night of 6/7 October—noted in the Dictionary of American Naval Fighting Ships as "particularly dark and rainy"—the ships were having trouble maintaining their stations in the convoy.
West Gate was sailing in the first column to the starboard of the guide ship, Sagua.

At 02:28 on 7 October, while about 250 nautical miles (460 km) south of Halifax, West Gate's steering gear engine jammed, sending the ship veering sharply to the port.
The crew put the ship's engines at half speed to try to drop out of the convoy.
Lieutenant Spencer, the chief engineer, and his assistant, Lieutenant (j.g.)
Hillery, headed to the machinery spaces to see about effecting repairs.
At 02:30, men on the bridge sighted the red light from the oncoming American, which had been steaming behind and to the port of West Gate.
Though the bridge ordered the engines raised to "full speed ahead" to avoid the collision, there was no time for the engines to respond before American's bow cut into the starboard side of West Gate, near the poop deck.

West Gate's engines were shut down while American backed out of the tangle.
West Gate quickly began to settle and the order to abandon ship was issued.
The chief engineer and his assistant, Spencer and Hillery, remained belowdecks long enough to extinguish the boilers and open safety valves to prevent the explosion of the boilers.
They finished the task just before the aft bulkhead gave way to the inrushing seawater.
Both arrived on deck in time to board lifeboat number 2, which had been held as long as possible for men in the after part of the ship.

Chief Gunner's Mate Michael B. Wallrath, who had assisted in lowering three lifeboats while he remained on board, jumped overboard after seeing to it that all the boats were away.
Wallrath was pulled into lifeboat number 6 just before a wave capsized it and drowned two of its occupants.
Lieutenant commander R. B. Vandervoort, USNRF, West Gate's commanding officer, remained on board until he felt sure that the entire crew had departed the sinking ship.
When he climbed up on the deckhouse to cut free a life raft and leave the ship, he discovered six men huddled on deck.
Vandervoort was able to get the six on the life raft, but the suction caused by West Gate's final plunge pulled him away and below the surface.
After he managed to get back to the surface, he clung to floating wreckage for two hours until pulled aboard the very raft he had missed earlier.
Vandervoort and the six men aboard the raft were rescued by one of American's lifeboats at 06:00, after some 3½ hours in the water.

A total of seven men from West Gate, two from lifeboat six and five others probably killed in the initial collision, lost their lives in the accident.
The U.S. Navy awarded Chief Gunner's Mate Wallrath a Letter of Commendation for his actions during the sinking of West Gate.
After taking on 7,187 long tons (7,302 t) of Army materiel, she departed for Bordeaux on 4 October in a convoy escorted by cruiser Denver. On the night of 6/7 October—noted in the Dictionary of American Naval Fighting Ships as "particularly dark and rainy"—the ships were having trouble maintaining their stations in the convoy. West Gate was sailing in the first column to the starboard of the guide ship, Sagua.
At 02:28 on 7 October, while about 250 nautical miles (460 km) south of Halifax, West Gate's steering gear engine jammed, sending the ship veering sharply to the port. The crew put the ship's engines at half speed to try to drop out of the convoy. Lieutenant Spencer, the chief engineer, and his assistant, Lieutenant (j.g.) Hillery, headed to the machinery spaces to see about effecting repairs. At 02:30, men on the bridge sighted the red light from the oncoming American, which had been steaming behind and to the port of West Gate. Though the bridge ordered the engines raised to "full speed ahead" to avoid the collision, there was no time for the engines to respond before American's bow cut into the starboard side of West Gate, near the poop deck.
West Gate's engines were shut down while American backed out of the tangle. West Gate quickly began to settle and the order to abandon ship was issued. The chief engineer and his assistant, Spencer and Hillery, remained belowdecks long enough to extinguish the boilers and open safety valves to prevent the explosion of the boilers. They finished the task just before the aft bulkhead gave way to the inrushing seawater. Both arrived on deck in time to board lifeboat number 2, which had been held as long as possible for men in the after part of the ship.
Chief Gunner's Mate Michael B. Wallrath, who had assisted in lowering three lifeboats while he remained on board, jumped overboard after seeing to it that all the boats were away. Wallrath was pulled into lifeboat number 6 just before a wave capsized it and drowned two of its occupants. Lieutenant commander R. B. Vandervoort, USNRF, West Gate's commanding officer, remained on board until he felt sure that the entire crew had departed the sinking ship. When he climbed up on the deckhouse to cut free a life raft and leave the ship, he discovered six men huddled on deck. Vandervoort was able to get the six on the life raft, but the suction caused by West Gate's final plunge pulled him away and below the surface. After he managed to get back to the surface, he clung to floating wreckage for two hours until pulled aboard the very raft he had missed earlier. Vandervoort and the six men aboard the raft were rescued by one of American's lifeboats at 06:00, after some 3½ hours in the water.
A total of seven men from West Gate, two from lifeboat six and five others probably killed in the initial collision, lost their lives in the accident. The U.S. Navy awarded Chief Gunner's Mate Wallrath a Letter of Commendation for his actions during the sinking of West Gate.
USS West Gate (ID-3216)