The Commandante Teste was built as a Seaplane Carrier / Tender, entering service in 1932. This was at a time when the aircraft carrier as a weapon was still very new. A seaplane carrier that could have some aircraft of its own and be able to support the large, long ranged, two and four engined flying boats, would be seen as being of value. Just six years later and the aircraft carrier has proved itself a formidable weapon. All the worlds navies are laying down aircraft carriers and converting other ships as well. The French had seen what the Japanese had done with their seaplane carriers being converted to aircraft carriers and proposed the same should be carried out on the Commandante Teste.
With the large internal hangar the Teste was a natural for conversion.
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