Lester Joseph Brain, AO, AFC (27 February 1903 – 30 June 1980) was a pioneer Australian aviator and airline executive. Born in New South Wales, he trained with the Royal Australian Air Force (RAAF) before joining Queensland and Northern Territory Aerial Services (Qantas) as a pilot in 1924. He was awarded the Air Force Cross in 1929, after locating the lost aircraft Kookaburra in northern Australia. Having risen to Chief Pilot at Qantas by 1930, he was appointed Flying Operations Manager in 1938. As a member of the RAAF reserve, Brain coordinated his airline's support for the Australian military during World War II. He earned a King's Commendation for his rescue efforts during an air raid on Broome, Western Australia, in 1942, and was promoted to wing commander in 1944.