First flight cover
On May 15, 1918, the first US regularly scheduled air mail route was inaugurated from Washington, DC, to Philadelphia and New York City. The air mail rate was twenty-four cents per ounce, and these flights marked the first use of the 24-cent red and blue combination air mail and special delivery stamp.
From Washington, Lt. George L. Boyle, piloting Curtiss plane no. 38262, pictured on the 24-cent air mail stamp issued on May 13, started from the Potomac Park Polo Grounds, which is located south of the city. Boyle carried one large pouch of mail weighing 140 pounds (about 6,600 covers), of which approximately 300 were for Philadelphia, 3,300 for New York City, and about 3,000 for redistribution to other points. The plane crashed about twenty-five miles south of Washington, Boyle having accidentally followed a branch railroad instead of the main line tracks to Baltimore and Philadelphia.
This mail (along with 1,330 other pieces that were picked-up from special red, white, and blue letter boxes) was flown on May 16 by Lt. James C. Edgerton to Philadelphia. The additional pieces were canceled on May 16, 1918, and some have "9 AM," "10 AM," or "11 AM" with the "1918" below. Perhaps a dozen or more covers are known with "May 16 / First Flight" in the cancellation.
Lt. H. Paul Culver flew the Philadelphia to New York mail, consisting of about 350 letters and cards weighing about twenty pounds. About 200 pieces were for distribution in the New York City area, and the rest was for points outside New York.
On the southbound flight from New York, Lt. Torrey H. Webb, with 2,457 pieces of mail and several packages and newspapers weighing 144 pounds, left Belmont Park at 11:30 a.m. and arrived at Bustleton, the Philadelphia terminus, at 12:30 p.m., from whence Lt. Edgerton flew to Washington with 136 pounds of mail.
Washington applied the cancellation in black and magenta; Philadelphia used black and blue-black; New York used magenta, purple, and black. A blue cancel on Washington covers and a carmine cancel on New York covers were reported many years ago but have not been seen in recent times.
The cover shown here, addressed to Malcolm H. Ganser, Philadelphia, bears the magenta, circular postmark used on the first airmail flight, reading, "AIR MAIL SERVICE WASH. N.Y. PHILA. / MAY 15, 1918 / FIRST TRIP" canceling two 12-cent Franklin stamps, used instead of the 24-cent airmail stamp.