14-09-2017, 10:11 AM
In 1968 the Society of Automotive Engineers formed the Aircraft Escape Emission Measurement Committee (E-31) whose burden was the development of acceptable measurement standards for aircraft engine exhaust characterization. The efforts of this committee have led to the issuance of two Recommended Practices for the aerospace sector, ARP 1179 "Measurement of exhaust smoke from aircraft gas turbine" and ARP 1256 "Procedure for sampling and continuous measurement of gaseous emissions from engines aircraft turbine ". These Recommended Practices have been largely adopted by the Environmental Protection Agency and promulgated in the Federal Register Volume 38, Number 136, Tuesday, July 17, 1973. Over the past three years, Pratt & Whitney Aircraft has been measuring emissions of aircraft gas turbine engines using on-line instrumentation systems designed in accordance with these Aerospace Recommended Practices and in response to the operational requirements of a large experimental engineering facility. In addition to an analysis of these systems, this document describes the experience gained from continuous testing programs in support of this test facility, taking into account the specific problems of sampling, sample handling, system accuracy and data logging and reduction.