The 'Italian Air Armada', General Balbo's squadron of 24 S.55X flying boats which flew from Orbetello to the Chicago World's Fair and back in July and August 1933. The nearest aircraft has serial (MM)45175 painted at the base of the tailfin. They also had civilian registrations allocated which were chosen for the pilots' names, for example I-BALB for Balbo's MM45174, but the tie-ups are not all known. Photo from: Dan Shumaker collection