When ordered to deploy to Europe, most units reported to the Aviation Concentration Center at Garden City, New York, which was the primary port of embankment. Units there were loaded onto transport ships for the transatlantic crossing. Liverpool, England and Brest, France were the primary ports of disembarkation, although other ports were used. Some aero squadrons arriving in England received additional training from the Royal Flying Corps (later Royal Air Force (RAF)), then were attached to RAF squadrons and deployed with them to France. Others received training and were sent to Winchester, Hampshire where they awaited their cross-channel transfer to France, using the port of Southampton.