BRAKING FRICTION COEFFICIENT AND CONTAMINATION DRAG OF A B727 ON CONTAMINATED RUNWAYS

This report summarizes the results of Federal Aviation Administration (FAA) B727 aircraft performance tests on winter contaminated runways at the Jack Garland Airport in North Bay, Ontario, Canada. The purposes of the tests were to measure the drag due to the runway surface contaminant and to determine the aircraft braking coefficient. The tests were conducted under a multi-year collaborative agreement among Transport Canada, the National Aeronautics and Space Administration (NASA), the FAA and the National Research Council Canada (NRC). The results of the unbraked tests for contaminant drag showed that the aircraft drag on snow-covered surfaces was essentially constant over a wide range of ground speeds. These results agree with test results on other aircraft, such as the NRC Falcon 20 and DH Dash 8, but differ significantly from conventionally accepted methods of determining contaminant drag. The results of the limited braking tests showed a predictable relationship between aircraft braking coefficient and the James Brake Index (JBI), agreeing with previous test results of the NRC Falcon 20, a smaller aircraft with similar landing gear configuration. It is recommended that further tests be conducted with the B727 on additional contaminated surfaces to confirm these results, and that tests be conducted on aircraft with multiple wheel bogies to determine whether differences exist.