An extract from: The Golden Age of Flying Boats by Peter Pigott
Updated: Sep 21, 2020
https://www.burntash.eu/flying-boats-golden-age

Through the war some 650 BOAC staff were employed at Poole on the flying boat services. At first, the Imperial Airways/ BOAC office was in the billiard room at the Antelope Hotel in the High Street. In mid-1942, the staff were moved to better quarters at the Poole Pottery, where there were four cubicles suited to Immigration examination and the main showroom for the Customs Hall.
In 1942, the flying boats were returned to Hythe temporarily — to give the Navy use of Poole Harbor to launch a diversionary attack on the Normandy coast, in case the North African landings failed. Customs were put in a hotel half a mile away from Hythe with Immigration officials in its greenhouse. On 23 March 1943, a BOAC PBY Catalina, G-AGDA, crashed on landing outside Poole during a training flight, killing 3 of the 6 onboard. During the build-up for “Operation Overlord” and D-Day, in May 1944, the flying boats were again removed from Poole, this time to the RAF flying boat base at Pembroke Dock, returning in September. Beginning 18 September 1945, RAF Sunderlands brought to Poole Harbor the prisoners of war held by the Japanese — those that would not have survived the journey home by ship. Through the coming months, the mercy flights from the Far East were to arrive at Poole almost daily.
The “phony war” from September 1939 to April 1940 allowed for some respite. The airline continued with flights to Rome, Brindisi, Athens and Alexandria while Italy was still neutral. With wartime requirements, the flying boats were given red, white and blue recognition stripes and now as part of BOAC on 1 April 1940, Lee-Elliott’s “Speedbird” would be added under the aircraft’s name.
The government of Australia was more precipitate about the war — it stipulated that the six Qantas flying boats — Coogee, Corio, Coorong, Carpentaria, Coolangatta and Cooee — should be kept south of Singapore and made available for Royal Australian Air Force (RAAF) use. With a frontline that extended from New Guinea to the New Hebrides, a few flying boats were to be impressed into service with the RAAF’s 11 Squadron. After negotiations with London, the BOAC flying boats Centaurus and Calypso that were at Rose Bay were commandeered and Coorong and Corio given in exchange. Centaurus was designated A18-10.6 in the RAAF and armed with under wing bomb racks capable of carrying 500-lb bombs, together with two former World War One Lewis guns mounted each side of the rear freight compartment, and a machine gun on top of the hull. Initially put on patrol, as the Catalinas became more plentiful, Centaurus and Calypso were used more as passenger carriers, assisting in evacuations.
In contrast, in 1940, with the German surface raiders Orion and Komet sinking shipping in the South Pacific, the government of New Zealand would use TEAL’s two S.30 flying boats Aotearoa and Awarua for military purposes. On loan to Imperial Airways since March 1939, they were flown to New Zealand to begin a scheduled service across the Tasman Sea, between Auckland and Sydney. Having sent its own small air force to Britain, New Zealand relied heavily on the two TEAL flying boats for maritime reconnaissance, putting one on an hour’s standby, even while continuing to maintain the scheduled air service to Sydney. Crews of both aircraft were part of the Royal New Zealand Air Reserve; gun mounts and bomb racks were installed on both aircraft as was the early use of radar. When the Pan American Clipper flights resumed in July 1940, with the number of Americans transiting through Auckland to Australia, this impacted on the TEAL flights.
The British government’s priority was an air service to the United States, its lifeline for influence and military purchases and with Pan American about to close its northern route through Botwood, it considered alternatives.2 The Empire flying boats barely had the range to make the Lisbon-Bathurst (Banjul) route to cross the Atlantic to Natal, and while Spain did grudgingly allow refueling at Las Palmas in the Canary Islands in 1940, given the strong fascist influence in its government, this could not be relied on.
The S.30 flying boats Cabot and Caribou, with their inflight refueling capability on Atlantic crossings, were chosen until the S.26 “G-class” became operational. But before this could happen, in an ill-conceived decision, the military impressed both into RAF service, arming them with machine gun posts. The three “G-class” flying boats were also taken over and equipped with power-assisted rear gun turrets.