The Ca.101 was a small trimotor used mainly by the Italian air force. I-ABCQ flew with a company from Milan, La Voce del Cielo (The Voice from Heaven), with four large loudspeakers mounted downward in the cabin and driven by four underwing generators. Patented by the Plane Speaker Co from the USA, the system was reportedly quite effective from altitudes of 3000 to 4000 feet. Whether used for Fascist propaganda or not, the aircraft is probably seen here during a July 1933 visit to the Netherlands where Verkade biscuits were advertised from the sky. Photo from: Nationaal Archief (Netherlands)
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