Following a distinguished 22-year career at sea, which included sailing around Cape Horn seven times (three times under sail), Noonan contemplated a new career direction. After learning to fly in the late 1920s, he received a "limited commercial pilot's license" in 1930, on which he listed his occupation as "aviator." In the following year, he was awarded marine license #121190, "Class Master, any ocean," the qualifications of a merchant ship's captain. During the early 1930s, he worked for Pan American World Airways as a navigation instructor in Miami and an airport manager in Port-au-Prince, Haiti, eventually assuming the duties of inspector for all of the company's airports.