It could also mean the Frederick Douglass - Greater Rochester International Airport. (If you look at the bottom right of the top stamp stamp it says 1936 ROC, New York. (ROC is the 3 letter code for that airport.)
ROC is the airport code for Rochester New York. Doubt there is any connection to China with these, given they are entirely in English and one is dated "1936 ROC NY" at the bottom right. These are some kind of Cinderella. Maybe issued by a philatelic group, or to commemorate some event. Or some company that no longer exists who's initials were "R.O.C."
I did a quick bit of research and found this on German language Wikipedia:
"In the 1930s, pilots in the United States began naming airports using the 2-letter National Weather Service abbreviations. In the 1940s, the number of airports began to exceed the expression (26 × 26 = 676). The airlines therefore started a 3-letter code format. Previous 2-codes were sometimes supplemented with an X at the end. (LA for Los Angeles became LAX.) IATA established the 3-digit codes in the 1960s."
So for that reason, and because the 3-letter codes don't use periods, I think the Rochester solution is a noble failure. I appreciate the effort.
I think these are poster stamps. It also looks like there is a "copyright" symbol before the "1936". "R.O.C." could be the printer or publisher of the stamps or the name of the company that promoted them.
Comments
These are some kind of Cinderella. Maybe issued by a philatelic group, or to commemorate some event. Or some company that no longer exists who's initials were "R.O.C."
"In the 1930s, pilots in the United States began naming airports using the 2-letter National Weather Service abbreviations. In the 1940s, the number of airports began to exceed the expression (26 × 26 = 676). The airlines therefore started a 3-letter code format. Previous 2-codes were sometimes supplemented with an X at the end. (LA for Los Angeles became LAX.) IATA established the 3-digit codes in the 1960s."
So for that reason, and because the 3-letter codes don't use periods, I think the Rochester solution is a noble failure. I appreciate the effort.
Mr Petersen also provided a link to the Poster Stamp Bulletin of May, 1936, highlighting this series.
https://alphabetilately.org/Cisfor/PSB/01-4-1.html?fbclid=IwAR3w-DI9QhqsEM6hKhd_FS7WjvV4B9gKuNMYkB2fiP07AQ_YkrpmpfuxTTU