From an FAA website: "August 1942..In late 1941, through early 1942, Pan American World Airways, with funding by the Air Corps Airport Development Program, expanded the Pan American 36th Street Airport and constructed a control tower atop the passenger terminal. The Pan Am tower was commissioned June 1942, and staffed by the CAA on August 3, 1942. The old airport was renamed Masters Field and turned over to the Navy. All commercial activities were moved to Pan Am’s 36th Street Airport and general aviation operations were sent to the Sunny South Airport. The tower structure was later moved from atop the terminal and relocated to the Dinner Key Seaplane Base where it served the U. S. Coast Guard until the activity was relocated to the Opa Locka Airport."

"The old airport" referred to above refers to All-American Airport/Master's Field on NW 27th Avenue where Miami-Dade College North Campus is now located. If it was not for World War II and the Navy's takeover of Master's Field, Miami's primary airport would probably be located at Master's Field instead of where Miami International Airport is now located.

Towers #1 and #2 were located at Miami Municipal Airport and Miami Master's Field because Miami Municipal had commercial airline service and Master's Field was about to get commercial service but World War II interrupted those plans.