During World War II, the RAF's Air Rescue Service (ASR) played a key role in rescuing thousands of highly trained Allied aircrews by carrying out rescue operations around the British Isles and other war-torn seas. Working closely with the Royal Navy, the ASR used both aircraft and speedboats to carry out its missions. One of the most famous was the British Power Boat Company Type 2 63 ft HSL, known as the "Whaleback" - "whale back" because of its distinctive curved deck. Another, equally frequently used term was the "Spitfire ASR". The unit, designed in 1937 by Hubert Scott-Paine, entered service in mid-1940. Initially, the defensive armament consisted of two Armstrong-Whitworth anti-aircraft turrets, each with a single Vickers machine gun. After the fatal Dieppe raid in August 1942, when many units were destroyed, it was decided to install two additional machine guns, one on each side, and a 20 mm gun in the rear, specially reinforced for assembly purposes. The armour, especially of the cabins, was also expanded, and although this naturally increased the weight of the unit, it nevertheless developed a fully satisfactory top speed of 36 knots thanks to the 500 hp Napier Sea Lions (a redesigned aircraft engine) and had a range of about 500 miles at an average speed of 25 knots. The crew consisted of 9 people, including the captain and medical staff. ASR bases were mainly located on the southeast coast of Great Britain, known as Hellfire Corner, due to the large number of accidents caused by constant air battles over the English Channel and the North Sea. Initially, the ASR rescue units were painted in bright yellow and black colors for better visibility, however, due to the increasing frequency of attacks by German aviation, it was deemed necessary to use gray camouflage. In 1944, the ASR RAF had at its disposal more than 300 fast lifeboats, which made it possible to cover the entire coast of Great Britain and many other important areas in the Mediterranean or even the Indian Ocean. Also, Malta, after the attacks of 1941, decided to establish the ASR base in the same year and by December 1942 alone, 125 valuable crews had been saved.