The Post Office Department adopted an unusual policy in the inauguration of Air Mail Route 71; official cachets were provided for the first flights in each direction on both the Montreal leg and the Ottawa leg of the route. To facilitate amendments to Civil Aeronautics Board route certificates (which required the signature of the President of the United States if a route crossed an international border), that portion of the route that crossed the Canadian border was numbered separately as Air Mail Route 71F. 

This cover was carried on the inaugural Air Mail Route 71 flight from Syracuse, New York to Washington, DC (where it was backstamped) and is listed in the Contract Air Mail Flights (CAM) Section of The American Air Mail Catalogue as 71S9.

Eastern Air Lines absorbed Colonial Airlines on June 1, 1956. Colonial Airlines had operated for more than 25 years without a passenger fatality.