AIR MAIL FIELD CANCELLATIONS
Special stations, under the jurisdiction of the local post office, were set up generally near airfields where mail planes would land and depart. This would allow faster transfer of air mail from one plane to the next, provide a facility to hold mail from the local post office ready for airmail service and a location to collect mail from planes which would then be taken to ground facilities for dispatch.
Special cancels were used as postmarks for departing mail and as backstamps showing arrivals. The initials “A.M.F.” are used to reference Air Mail Fields – the term used from 1924-1959 – when the name was changed to Airport Mail Facility.
The American Air Mail Catalogue, to identify a specific A.M.F. cancellation, uses the following methodology:
The first part of the listing uses a three-letter airport code for the airport where the station was located. The second part identifies when the cancel was used, listed in chronological order for that particular cancel. The third represents the type of cancel used. The types of cancels are divided into eight categories.
“SAC” represents the Sacramento, California A.M.F. The “1” indicates the cancel was used between 1925-27 and the “Type 1” indicates the use of a rubber handstamp with a 4-bar killer.
There are also a few ‘stealth’ A.M.F. cancels where the facility did not have an official Post Office Department canceller but functioned as an A.M.F. The AAMC, Fifth Edition, p752 is a good example: -Air mail was accepted at the Albany Airport by post office clerks stationed at the field and cancelled with the regular Albany handstamp canceller and the inaugural cachet in the absence of a regular air mail field cancellation stamp. Such covers cancelled at the airport are identified by the time. “10 A.M.”-
Reference: American Air Mail Catalogue Fifth Edition, Volume Two, pages 501-585. Also p.752 (Albany) ALB 1 Type 6 and 768 (Ft.Worth) GSW 1 Type 6.