Hospital Ships (AH)

Photograph of hospital ship

National Archives #80-G-K-17386

The function of hospital ships was to transport wounded personnel to a place of safety.  However, most hospital ships, particularly in the U.S. Navy, were as capable of treating the wounded as most shore facilities.  U.S. hospital ships invariably were equipped with modern operating rooms and medical laboratories and carried large quantities of medical supplies.

Under international law, hospital ships were immune to attack or seizure but could be diverted or detained under certain circumstances.  They were required to fly the Red Cross along with their national flag and to be painted gleaming white and marked with the Red Cross and green strakes.  At night, they were required to be brightly illuminated.  They could carry no armament, ammunition, or other contraband and were to sail independently of military forces.

Both sides violated the rules at times, but there is little evidence that the Allied violations were deliberate.  The most serious Allied violation occurred when the Awa Maru was sunk by the U.S. submarine Queenfish. The commander of Queenfish had neglected to carefully read the communications outlining the route of the Awa Maru and attacked by radar during foggy conditions, apparently unaware that his target was a hospital ship.   He was relieved of command and received a Letter of Reprimand.  The United States initially agreed to replace the ship, but reneged when evidence came forward that the ship was carrying contraband at the time of the torpedoing.

The most notorious Japanese violation was the sinking of Australian hospital ship Centaur by I-177 on 14 May 1943. The ship was clearly marked and brightly lit and visibility was good when it was torpedoed, with the loss of 268 passengers. Other serious violations involved the Op Ten Noort, a Dutch hospital ship.  The Japanese repeatedly violated international law in connection with this ship, and there is no question that this was deliberate rather than negligent. 

There were also a number of kamikaze attacks on U.S. hospital ships later in the war. For example, on the evening of 28 April 1945, Comfort was hit by a kamikaze that circled the fully illuminated and properly marked hospital ship once before diving into its superstructure and killing the entire surgical staff.

American commanders in the Pacific were deeply suspicious of the heavy hospital ship traffic under the Japanese flag, a suspicion that was confirmed by the spy network at Singapore and by decoded Japanese messages showing the Japanese were attempting to use the hospital ships to transport troops. However, the great secrecy surrounding cryptanalysis meant that the Allied commanders could neither act on nor publicly disclose this violation, which did not come to light until the 1990s (Weinberg 1944).

However, both sides usually respected the hospital ship convention.  For example, Solace was present during the attack on Pearl Harbor but was untouched.  The famous film footage of Arizona exploding was filmed from her deck. Likewise, an old coastal steamer, Mactan, was dressed in hospital colors during the seige of Bataan and transported a load of casualties to Australia unmolested by the Japanese, who had been notified of its sailing via Swiss diplomats. The voyage took a miserable 27 days, during which the wounded suffered from ants infesting the ship (and getting into the bandages), an engine breakdown, and a violent storm and barely missed being caught in the raid on Darwin. At the end of the trip, the Mactan was ruled "entirely unseaworthy."

Japanese hospital ships

Hikawa Maru

U.S. hospital ships

Comfort class

Haven class

Solace class

Dutch hospital ships

Op Ten Noort


Australian War Memorial (accessed 2010-1-26)

Blair (1975)

Cowdrey (1994) (accessed 28 December 2006)

Gilbert (1989)

Morison (1959)

Thompson (2005)

Weinberg (1994)

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