The first British Liberators had been ordered by the Anglo-French Purchasing Board in 1940. After the Fall of France the French orders were in most cases transferred to the United Kingdom. The RAF found, as did the US, that global war increased the need for air transports and early type bombers and seaplanes were converted or completed as cargo carriers and transports. LB-30As were assigned to transatlantic flights by RAF Ferry Command, between Canada and Prestwick, Scotland. The first Liberators in British service were ex-USAAF YB-24s converted to Liberator GR Is (USAAF designation: LB-30A). The aircraft were all modified for logistic use in Montreal. Changes included the removal of all armament, provision for passenger seating, a revised cabin oxygen and heating system. Ferry Command's Atlantic Return Ferry Service flew civilian ferry pilots, who had delivered aircraft to the UK, back to North America. The most important role, however, for the first batch of the Liberator GR Is was in service with RAF Coastal Command on anti-submarine patrols in the Battle of the Atlantic.