The Lockheed L-188 Electra is an American turboprop airliner built by Lockheed. First flown in 1957, it was the first large turboprop airliner built in the United States. Initial sales were good, but after two fatal crashes that led to expensive modifications to fix a design defect, no more were ordered. With its unique high power-to-weight ratio, huge propellers and very short wings (resulting in the majority of the wingspan being enveloped in propwash), large Fowler flaps which significantly increased effective wing area when extended, and four-engined design, the airplane had airfield performance capabilities unmatched by many jet transport aircraft even today—particularly on short runways and high field elevations.  Jet airliners soon supplanted turboprops for many purposes, and many Electras were modified as freighters.

No cachet was provided for mail carried on the inaugural flight.

This cover was carried on the September 8, 1960 American Airlines’ Air Mail Route 4 inaugural Electra Jet flight from Rochester, New York to LaGuardia Airport in New York (where it was backstamped).