Introduction 

Research into B-17Es, B-17Fs and and B-17Gs operated by RAF Coastal Command as the Fortress IIA, II and III led me to touch on the 20 B-17Cs acquired by Britain. All 20 Fortress Is were initially assigned to 90 Squadron for what were considered operational trials over Europe. Apart from the knowledge gained in high-level bombing operations, the trials proved notably unsuccessful, as has been comprehensively documented elsewhere. Despite this lack of success, four Fortress Is were dispatched to Egypt, initially on a two-month trial basis, while a further five examples were assigned to Coastal Command for type training and service as hacks. Their use in Egypt and with Coastal Command is covered in the book Boeing B-17 Fortress in RAF Coastal Command Service, noted elsewhere on this site.

Further research into the acquisition, preparation and delivery of the 20 Fortress Is revealed a unique set of circumstances that has received little attention to date. This set of pages endeavours to expand and improve the record.

The Need

By the mid-1930s there was a growing realization among the British authorities that the country’s aviation industry did not have the capacity to supply aircraft to meet the expanding rearmament plans to combat Nazi Germany.

To help address the looming shortfall, the Ministry of Supply dispatched the Weir Mission, headed by Scottish industrialist James G Weir, to visit Canada and the United States to investigate the potential for purchasing suitable aircraft. The Mission sailed to New York aboard the RMS Queen Mary on April 25, 1938, with the majority of members returning on the same vessel a month later. 

Aircraft types to be examined included bombers with a specified range of 2,000 miles and a bomb load of 4,000 lbs, including the Boeing B-17 which, by the time of the Mission’s arrival, had evolved into the B-17D model.

The Mission, which included Air Commodore Arthur T Harris, the future chief of Bomber Command, visited Boeing’s facilities at Seattle in Washington State, where it was limited to viewing the exterior of the B-17. Despite misgivings expressed by Harris regarding the type’s limited defensive armament, the company was subsequently requested to provide a quotation based on an 18-month production run and delivery by air to the United Kingdom.

The Purchase

On December 12, 1940, the United States Army Air Corps (USAAC) released 20 new Boeing B-17C aircraft from a total production of 38, with the condition that USAAC observers would travel to Britain to collect feedback from combat and maintenance crews. The British government purchased the B-17s on a cash-and-carry basis, whereby they paid for the aircraft and their delivery to Britain. Covered by contract A-5077, the 20 B-17Cs were the last of a variety of types contracted from American aircraft manufacturers from September 1939 until Lend-Lease came into effect in March 1941.

The full 38 aircraft were allocated USAAC serials in the range 40-2042 to 40-2079 with the 20 examples assigned to Britain selected at random. These were initially marked with incorrect Air Ministry serials, AM518 to AM537, later revised to AN518 to AN537.

First Steps to Delivery

While the transatlantic ferrying of twin-engined aircraft such as the Lockheed Hudson and Consolidated Catalina to Britain was by now well under way with ____ aircraft delivered, there were few airmen available with the skills to ferry large, four-engined aircraft across the North Atlantic. The solution was to select an initial group of thirty RAF airmen – including first and second pilots, navigators, radio operators and flight engineers – from mostly Coastal Command units and ship them to Montreal, Canada, by way of Halifax at the end of December 1940. These airmen had typically completed their first operational tour and acquired extensive experience in long-distance, over-water flying. 

Following assembly at RAF Uxbridge, the airmen sailed from the Clyde on the troopship SS Léopoldville on December 18, 1940, arriving at Halifax on December 28. Post-convoy escort to Halifax was provided by the battleship HMS Royal Sovereign. The airmen then proceeded by train to ATFERO headquarters in Montreal, arriving on December 31.

Last edit: February 23, 2026