The President of the United States of America takes pleasure in presenting the Distinguished Flying Cross to Commander Donald Bartram MacDiarmid, United States Coast Guard, for heroism and extraordinary achievement in aerial flight as Pilot and Co-Pilot of a PBM type plane while carrying out conclusive experiments concerning Open Sea Seaplane Operations off the coast of California during the early part of 1945. Participating in forty-five open sea landings and take-offs in all types of weather, Commander MacDiarmid successfully brought his plane to its base each time, sustaining only minor damages. Making scientific observations throughout his experiences, he compiled these into a lucid and comprehensible form in the first authoritative information concerning landing and take-offs of airplanes at sea. His work has been an invaluable source of information and guidance for airmen who need to land airplanes at sea, his outstanding skill and devotion to duty in carrying out his hazardous work reflect the highest credit upon Commander MacDiarmid and the United States Naval Service.