Private First Class Ainsworth was a member of Company G, 3rd Battalion, 7th Marines, 1st Marine Division. He was Killed in Action while fighting the enemy at the "Punchbowl" in North Korea on 19 June 1951.

Ainsworth was awarded the Purple Heart, the Combat Action Ribbon, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.