Having retired from work as a Quality Assurance Manager in the nuclear power industry, Phil Butler continued his research in the United Kingdom's aviation heritage. Phil's interest in aviation started while he was at school. He was in the Air Cadets and was an early member of the Merseyside Aviation Society in his home city of Liverpool. During his membership of the Society he contributed to its Journal and was involved in the research, editing and production of a number of books published by the Society, such as a directory of airfields in the British Isles, the history of aviation in Ireland, the history of Liverpool Airport, registers of British Gliders, of 'Class B' registered aircraft, and of the 'Air Min' aircraft, the last of which formed the nucleus of this current book.