1939 Experimental Route 2001 First Flight Autogiro Airmail Covers — Philadelphia & Camden Matched Pair — Scott C23 — July 6, 1939

These are genuine 1939 first-flight airmail covers from an important event in American aviation and postal history. 

Both envelopes commemorate Experimental Air Mail Route 2001, inaugurated on July 6, 1939, between the main Philadelphia Post Office and Camden Central Airport in New Jersey.

This was not an ordinary airplane route. The mail was carried by a Kellett KD-1B autogiro, operated by Eastern Air Lines. An autogiro was an early rotary-wing aircraft—a technological predecessor/cousin of the modern helicopter. The Smithsonian National Postal Museum confirms that the U.S. Postal Service began this service on July 6, 1939, carrying mail between Camden Airport and the roof of Philadelphia's main post office. 

The service was historically significant because it represented the first scheduled U.S. airmail service using a rotary-wing aircraft, and contemporary accounts described it as the first scheduled rotary-wing mail service of its type. 

 

The cancellations show the two ends of the route:

Philadelphia cover:
PHILADELPHIA, PA. — JUL 6 — 2 PM — 1939

Camden cover:
CAMDEN, N.J. A.M.F. — JUL 6 — 2:30 PM — 1939

The "A.M.F." means Air Mail Field. A historical account of Camden Central Airport specifically describes these two varieties: Camden-cancelled covers represented the inbound trip to Philadelphia, while Philadelphia-cancelled covers represented the outbound trip to Camden. 

Each envelope carries the attractive 6¢ red-and-blue Eagle airmail stamp, generally catalogued as Scott C23, issued in 1938.

Six cents was the appropriate airmail denomination.