Donald was a Flying Officer for the RCAF in World War II. He trained at Victoriaville, Quebec and St. Eugene, Ontario, and received his wings as a fighter pilot at Uplands, Ontario. He was killed in a flying accident in England. An Ottawa newspaper published this story on him:

“FO. D. M Eastman Killed in Crash

FO. Donald Mervyn Eastman, R.C.A.F., was killed in a flying accident overseas on Saturday, June 9, according to word received by his parents, Mr. and Mrs. J. M. Eastman, of 241 Carling avenue.

The 21-year-old Air Force officer, a Glebe Collegiate graduate, had been attending Macdonald College at Ste. Anne de Bellevue at the time of his enlistment. After training at Victoriaville, St. Eugene and Uplands and getting his wings as a fighter pilot, he went overseas, and had just completed fighter operational training on Spitfires a short time before VE-Day. From a reserve pool for replacements he had volunteered for Pacific duty.

FO. Eastman was a member of St. James United Church. He was an enthusiastic skier, fishermen and hunter.

In addition to his parents to mourn his loss a sister, Doris, and a grandmother, Mrs. E. B. Eastman, all of Ottawa.”

His parents tombstone in Ontario mentions that he was “Killed on active service, overseas”.