Airways were the Handley Page HP42 and HP45 four-engined bi-planes Hannibal G-AAGX series and Heracles G-AAXC series. In 1938 the first four-engined monoplanes, Armstrong Whitworth Ensign series (G-ADSR) came into service. In November 1938 the Chamberlain government decided that Imperial Airways , which served Empire routes, should be merged with British