13262 Corporal Douglas Isbister Cooper, 1917-5/12/1942.

Douglas Cooper's death is mentioned but briefly in stories available on my go-to source, "Papers Past."  It required a search of other sources and using the date and the Official History of the NZ Medical Services in the Middle East and Italy to find the circumstances around his end:

Sinking of SS Chakdina

On 5 December two ships with two escort vessels left Tobruk for Alexandria at 5.30 p.m. The larger of the two, the SS Chakdina, under arrangements made by ADMS Tobruk, Colonel Fulton, carried 380 wounded, including 97 New Zealanders. These wounded had been held up inside Tobruk and the decision had been made to evacuate them by sea to base hospitals in Egypt. Most of the ninety-seven wounded New Zealanders on board were stretcher cases and were put in the aft hold between decks.

Just as the moon was rising, a little after nine o'clock, the Chakdina, which was not a hospital ship, was attacked by a torpedo-carrying aircraft. Approaching at a height of barely 50 feet, the plane released a torpedo which exploded in one of the aft holds. Immediately the ship began to sink by the stern and in three and a half minutes it had disappeared.

Of those below deck — for the most part prisoners and the seriously wounded — few were able to escape. The men on deck had a better chance of fending for themselves, but many, too, were drowned, some by the upsetting of lifeboats, others by the suction of the sinking ship. For the wounded trapped in the aft hold there was small chance of escape, but there were several remarkable escapes when the exploding boilers caused an upward surge of water that thrust some to the surface. These and others were picked up by ships of the convoy which carried out rescue work for two hours despite continued air attacks. Eighteen of the New Zealand wounded were picked up by the destroyer Farndale, and possibly some by the Thorgrim, but up to 79 were drowned. This was the only major misfortune in the evacuation of wounded in 2 NZEF during the war, and the decision to use the Chakdina as a hospital ship, without markings, appears unjustifiable.

Major Williams, OC 4 Field Hygiene Section, and three members of the ADMS's staff were on board, one of the staff being amongst the missing.

Douglas Isbister Cooper is recorded as having volunteered for the Army at the beginning of 1940, described as "university student." He was conferred with a Bachelor of Arts by the University of Otago in June of 1941. In January of 1942 he was listed as "missing, believed drowned."

The "Chakdina," as mentioned, was an armed boarding vessel which had been commandeered by the British for the evacuation of wounded form the besieged port of Tobruk.  There must have been not time or resources to mark the ship with lit Red Cross markings which would have shown it was not a combat vessel. An Italian torpedo bomber sank the ship at 9.35pm, December 5th. The "Chakdina" sank very quickly and about 400 men drowned, including prisoners of war who were on board.

Oamaru Cemetery.