1988 36c IGOR SIKORSKY USA AIRMAIL STAMPS IN GOOD UNUSED CONDITION1988 36c Igor Sikorsky AirmailIssue Date: June 23, 1988First City: Stratford, ConnecticutQuantity Issued: 111,550,000Printed by: Bureau of Engraving and PrintingPrinting Method: Lithographed, engravedPerforation: 11Color: Multicolored features Igor Sikorsky, a native of Czarist Russia, who was a leading aircraft designer. Driven out of Russia by the Revolution, he became an American citizen. Sikorsky built the first practical single-rotor helicopter. The craft pictured on the stamp was successfully flown in 1940.