A33N Engine Completes FAR-33 150 Hour Endurance Test
Cobra Aero finished endurance testing on the A33N 33cc, two-stroke, EFI engine. The 150 Hour Profile run followed standards established by the Federal Aviation Regulations, Part 33. Cobra conducted the test at their facility in Hillsdale, Michigan. Power4Flight’s Mark Johnson assisted Cobra with setting up the EFI system.
Completion of the test required 4 design revisions before a full 150 hour run was completed. The 4th engine configuration finished the run with all systems fully operational. The post run tear-down showed the piston to be in very good condition considering it had 180 hours (30 hours prior to the test) of run time on it. The crankshaft assembly as well as the top and bottom-end rod bearings showed no signs of abnormal wear.
Overall the final results provided great confidence in the endurance of this engine. The main change being explored is a different air filter because the one used in the test had an average life-span of 44 hours.