Air Service, United States Army David Endicott Putnam (December 10, 1898 – September 12, 1918) was an American flying ace of World War I.

He is described in the camp newspaper Seen and Heard as “Modest and unassuming, yet genial and a good mixer, of high moral standard; he was without question the most popular boy in the camp.”[citation needed] Becket director, Henry W. Gibson affirms that: “The sense of fair play, of consideration for the other fellow, of physical bravery, of moral courage—all of these qualities were given a chance to express themselves in his camp life.” Henry Gibson recalled that Putnam approached him at his tent and said, "I am going across the seas to get in the big fight."

When the United States entered the war, Putnam joined the United States Army Air Service as a first lieutenant and briefly assumed command of the 134th Aero Squadron before joining the 139th Aero Squadron as a flight commander.

He wrote to Henry Gibson, director of Camp Becket-in-the-Berkshires, where Putnam had been a camper and counsellor, "Can you imagine anyone falling 20,000 feet, nearly four miles, smashing a machine to kindling wood and only getting a broken tooth out of it all?

During his time abroad, Becket director, Henry W. Gibson corresponded with Putnam until the former received a returned letter in his name, with the words ‘deceased’ written on the envelope.

Gibson never opened it, and later used it to illustrate in the camp chapel service: we must never delay telling what is on our hearts before it is too late.

Putnam shot down thirteen confirmed planes, but unconfirmed totals range from twenty-six to thirty in German territory.