 The prototype, named "Antarès", entered service with "Escadrille E8" of the French Navy in September 1939, flying its first patrol mission over the Atlantic on 20 September 1939.Additional large orders for Potez-CAMS 141s were placed shortly after the start of the war, with delivery expected from June 1940, but these orders were cut back owing to changing priorities and the realisation that the loss rate of long range flying boats was very low.No production aircraft had been completed by the time of the Armistice in June 1940, with "Antarès" being evacuated to Port Lyautey in Morocco.