Review of Aviation Lubricating Oil Specification

MIL-L-6081 specification for the oil using mineral oil as base oil could not meet the requirement.US Air Force set MIL-L-7808 specification for the oil takingⅠtype diol ester base stocks as base oil in 1951,and evolved it to MIL-PRF-7808 L in 1997.Along with the development of air engine′s thrust weight ratio to high level,the aviation lubricating oil numbered MIL-L-7808 specification occurred sludge during use,which caused the friction and wear of engine components.So the aviation engine oil needed to further improve its thermal stability.US navy prepared MIL-L-23699 specification for the oil which was typically made with polyol ester base stocks in 1963.It was upgraded to MIL-PRF-23699 F in 1997.SAE developed MIL-PRF-23699 F to the latest SAE AS 5780 specification in 2007.In this paper,the driving force and performance requirement for MIL-PRF-7808 L and SAE AS 5780 were presented mainly.With the development of the airplane to high speed and high performance,the compound with excellent thermal and oxidational stability,such as perfluoropolyether etc.,maybe meet the specification requirements of future aviation lubricating oil.