The World’s first dedicated aviation engine oil
The rapid development of aviation during the 1920s and 1930s, enabled by the invention of more powerful engines, saw aircraft flying faster, further, and higher. However, the oils used to lubricate these engines originated from those developed for cars, with vegetable oils, usually castor oil, the most common.
As engine performance increased, along with higher temperatures and pressure, there was an urgent need for lubricating oils specifically designed to meet the needs of aircraft engines. In 1931, Shell Aviation responded to this challenge with the introduction of AeroShell, the first lubricant exclusively designed for this new generation of engines. This high-quality mineral oil was tested extensively in collaboration with Shell customers and passed the stringent tests required by the aircraft industry and the new generation of airlines. AeroShell solved most of the problems associated with existing castor oils, allowing recirculation of the oil, drastically reducing oil consumption, and ensuring metal parts were protected by a thin oil film.
In 1934, Rolls-Royce and Imperial Airways, after extensive testing, declared that AeroShell was the officially approved oil for use in their engines. Writing to Shell to approve the new oil, Rolls-Royce said: “We have to inform you that we have recently carried out a 100-hour test on one of our ‘Kestrel’ engines using AeroShell oil of your manufacture. The condition of the engine after the test was found to be excellent and the use of AeroShell oil for all aero engines of our manufacture is now approved by us.” Imperial Airways also approved AeroShell for use in all its aircraft the same year, with many others soon following suit.
However, throughout the 1930s, engine performance and size were increasing so rapidly that further advances in lubrication were needed to protect the engines and ensure aircraft safety. The new class of air-cooled engines needed an oil that gave them complete freedom from issues like ring-gumming, excessive sludging, and corrosion of any special bearing materials.
Shell responded again with the development AeroShell Oil 100, a new grade of engine lubricating oil. This lubricant quickly obtained the approval of the Bristol Aeroplane Company, whose Pegasus engine powered the Short Empire flying boats of Imperial Airways. This exceptional aircraft, with its ability for long transoceanic and transcontinental flying, helped open-up the airways from Europe to Africa and the Far East.
Wonderfully nostalgic and elegant baggage stickers from Imperial Airways, Deutsche Lufthansa, KLM, and Air France overlap each other on an advertisement from a 1937 edition of Shell Aviation News magazine. The headline reads: “They all use AeroShell lubricating oils,” showing just how widespread use of the range of engine oils had become.
Shell’s support for the aviation industry and engine manufacturers continued over the following decades with the development of its range of lubricants for both piston and turbine engines. When civil aviation went supersonic with Concorde, Shell worked with Rolls-Royce to develop Aeroshell Turbine Oil 555, an advanced synthetic oil capable of engine protection at greater combustion temperatures and load-carrying requirements of supersonic flight.
Shell Aviation Magazine, 1931-1938.
Shell News, March 1951, p. 8-10.
Shell Aviation News, February 1938.
aircraft engine development (pilotfriend.com)
R. van Egmond and A. Westra, Shell and aviation. The story of more than a century of collaboration. Shell International B.V., 2019, p. 80-81|
Shell Aviation News, 1975 and 1976.
Shell historical archives.
Shell supports de-Havilland in engine testing for the world’s first passenger airliner.