 After four months of the mail being flown by the Army, all flight operations were taken over by the USPOD's Aerial Mail Service on August 12, 1918, using a fleet of six purpose built JR-1B mail biplanes designed and constructed by the Standard Aero Corporation of Elizabeth, New Jersey, and flown by civilian pilots hired by the Post Office Department.After a number of "pathfinder" flights made in September, November, and early December, the first flight providing scheduled east-west service between New York and Chicago occurred on December 17, 1918.Flight operations moved 9 miles northeast to the College Park Air Field.