This metric SAE Aerospace Information Report (AIR) details a ball-on-cylinder (BOC) test device and specifies a method of rating the relative lubricity of aviation turbine fuel samples. The BOC produces a wear scar on a stationary steel ball by forcing it with a fixed load against a fuel wetted steel test ring in a controlled atmosphere. The test ring is rotated at a fixed speed so its surface is wetted by a momentary exposure to the fluid under test. The size of the wear scar is a measure of the test fluid lubricity and provides a basis for predicting friction or wear problems.
ASTM D5001 is a more contemporary standard for fuel lubricity testing that is currently preferred by the Industry. The AE 5B Committee, therefore, decided to reference ASTM D5001 as the preferred method in ARP1794 and then stabilize ARP1794. Revision A of ARP1794, containing the reference to ASTM D5001, has been published, and the next step is to stabilize the standard.