ILS FLIGHT INSPECTION POSITIONING SYSTEM TEST AND EVALUATION.

Positioning accuracy data show that the two standard deviation measures of dispersion were 0.03 deg in the initial part of the ILS approach. In the near area of the approach, the FIPS performance may have exceeded the capability of the measurement instrumentation. Static tests near the threshold produced a two standard deviation measure of dispersion of 0.01 deg and less. The flight inspection aircraft, measuring for effects on the commissioned ILS, report that the FIPS installation has no measurable influence on the ILS. With respect to providing guidance for flight inspection use, the FIPS produces courses, flyable simultaneously by a pilot when used in conjunction with a standard ILS. The conclusion is reached that the interferometer technique used is feasible as an accurate measurement system. Some redesign and improvements to the feasibility hardware are suggested. Author