sentences:  A second permanent army airfield, Albrook Field, opened in 1932 due to France Field becoming too small for the numbers of aircraft being assigned to the Canal Zone, as well as having a poor landing surface; offering no room for expansion, and providing little defense for the Pacific entrance to the Panama Canal.A third airfield, Howard Field was built on the Canal Bruja Point Military Reservation, opening on 1 December 1939.By 1940, a rapid increase in the number of flying squadrons in both the Canal Zone as well as in Panama as a result of the pre–World War II mobilization of the Air Corps warranted a new organization, and the Panama Canal Air Force was created as a major command.