The Development of an Aviation Fuel Thermal Stability Test Unit

A test unit has been developed by Rolls-Royce for the U.S. Navy to use in evaluating fuel thermal deposition typically found in various aircraft engine components. Although the current Jet Fuel Thermal Oxidation Tester (JFTOT) provides a qualitative thermal stability evaluation, it may not be able to predict in-service problems. Conditioning and testing of the fuel under realistic conditions is crucial if one is to predict deposit formations accurately. Engine fuel deposit evaluations and evidence from unpublished Rolls-Royce laboratory rig tests were used to help design a test unit that would address fuel stability problems in current or future aircraft. The Aviation Fuel Thermal Stability (AFTS) test unit embodies test modules that were selected with extensive fuel systems experience to enable the evaluation of thermal deposition in various fuel components using properly conditioned fuel. The test modules are controlled and results are recorded by a computer. This paper includes a review of the AFTS test unit design and preliminary test results thereof.