JOINT WINTER RUNWAY FRICTION MEASUREMENT PROGRAM (JWRFMP): INTERNATIONAL RUNWAY FRICTION INDEX (IRFI) VERSUS AIRCRAFT BRAKING COEFFICIENT (MU)

This is a Joint Winter Runway Friction Measurement Program (JWRFMP) report on aircraft and ground friction measuring device (GFMD) research and data collection as related to the capability of a runway surface to provide aircraft wheel-braking action during winter operations. The project was led by Transport Canada and the National Aeronautics and Space Administration, with support from National Research Council Canada, the U.S. Federal Aviation Administration, the Norwegian Air Traffic and Airport Management (now Avinor), France's Direction gnrale de l'aviation civile, and organizations and equipment manufacturers from Austria, Canada, France, Germany, Norway, Scotland, Sweden, Switzerland, and the United States. The data was used to compare the International Runway Friction Index (IRFI) of the GFMDs with the Aircraft Braking Coefficient (Mu). During the year 2000, ASTM E 2100 standard "The International Runway Friction Index" was issued. The use of IRFI reduced the standard error in measured friction of GFMDs from as high as 0.2 (without IRFI) to an average under 0.05. IRFI correlations to the aircraft reduced the variations of the slopes of the correlations by 50 percent as compared to GFMDs without IRFI.