The son of a doctor, Mendis was educated at S. Thomas' College. He joined the newly formed Royal Ceylon Air Force as its fifth recruit as a Cadet Officer. On 8 August 1951, Mendis and Cadet Officer D. De S. Seneviratne were sent to Britain for their training at RAF College Cranwell. After graduating on 6 April 1954, Mendis specialized in De Havilland Vampires until he returned home.
Career
When the government decided to deploy more transports instead of the Vampires, Mendis trained for Airspeed Oxfords and later took command of the newly formed No. 2 Squadron. Later he would become a flying instructor and command the Royal Ceylon Air Force Flying School. Graduating from Defense Services Staff College, Wellington, India, he was appointed Senior Air Staff Officer at Air Force Headquarters, and in 1968 he attended the Imperial Defence College in London. Upon his return in 1969 he was made Chief of Staff, and was made Commander of the Air Force in January 1971. Three months later, the RCyAF was mobilized for combat for the first time when the 1971 JVP Insurrection began. Though unprepared for a full-scale insurrection, with limited aircraft, under Mendis' command, the Air Force responded effectively. At first, it carried out troop and supply transport to stations under attack, then it turned to ground attacks. The insurrection was brought under control in two months. Following the insurrection, military spending was drastically cut as a result of major economic problems faced by the country. As a result, Mendis was forced to create Helitours with Air Force planes and pilots to finance the operation of the Air Force. One of his major contributions to the Air Force was the creation of the current management structure, including the board of management. He established the Air Force Academy at SLAF China Bay for officer training and the Electronic Maintenance and Training school at SLAF Ekala, Trade training School at SLAF Katunayake for ground crew training. He retired from service in 1976 as an Air Marshal.
Later work
After retiring he went on to work as Chairman, Air Ceylon; Commissioner General, Civil Defence and Aviation; member, Reserve Affairs Council and Chairman, Civil Aviation Authority of Sri Lanka. For his service to the country he was awarded the title Deshamanya from the Government of Sri Lanka and in 2007 he was promoted to the rank of Air Chief Marshal along with 9 other former service chiefs.
Family
He married Charmaine in 1957, and they had 3 children. One of his grandsons is a midshipman at the US Naval Academy who graduated with the Class of 2010.
