From mid-1942 to 1945, Conn ceased all production of musical instruments for civilian use to manufacture flat & mounted compasses, altimeters, gyro-horizon indicators, and other military instrumentation. A special application of Conn's "Coprion" process—creating seamless brass bells by depositing copper on a mandrel—was to manufacture silver bearing inserts for the Wright Cyclone airplane engines. In winter 1946-47, production was again interrupted, by a 15-week labor strike. The loss in sales from those disruptions and increased competition from other manufacturers such as Selmer (Paris) and King (H. N. White) caused a serious decline in Conn's status as a major band instrument manufacturer. Conn first responded by expanding their lines of electronic musical products, developing the "Connsonata" electronic organ in 1946. They later developed the "Connstellation" model wind instruments to revitalize those product lines (28M alto saxophone with help from Santy Runyon, 1948, and brass instruments, mid-1950s). The Connstellation brasswinds remained a premium line through the 1960s.