Pass-to-Coverage Computation for Arbitrary Gear Configurations in the FAARFIELD Program

The U.S. Federal Aviation Administration (FAA) adopted FAA Rigid and Flexible Iterative Elastic Layered Design (FAARFIELD) as its standard thickness design procedure for airport pavements in September 2009. FAARFIELD incorporates the effects of airplane wander through a computed pass-to-coverage (P/C) ratio. The P/C ratio is computed at the top of the subgrade for flexible pavements and at the pavement surface for rigid pavements. This document describes the FAARFIELDimplemented procedure that allows the computation of P/C ratio for arbitrary gear configurations. This procedure also allows the calculation of pavement thicknesses for arbitrary, user-defined gear configurations. This feature was not available in previous FAARFIELD versions.

DOT/FAA/TC-TN12-47
Author: Izydor Kawa