On September 6, 1994 Ireland issued a set of five "anniversaries" stamps. The set's high value, 52p stamp (Sc #943) commemorates the 75th anniversary of the first non-stop flight across The Atlantic Ocean. The flight was made in June of 1919 in a modified Vickers Vimy bomber aircraft flown from St. John's, Newfoundland to Clifden, Ireland. It was piloted by British aviators John Alcock and Arthur Brown.
From Wikipedia, "The Secretary of State for Air, Winston Churchill, presented them with the Daily Mail
prize for the first crossing of The Atlantic Ocean by aeroplane in less than 72 hours. A small amount of mail was carried on the flight, making it the first transatlantic airmail flight."