Study on Aircraft Altitude Keeping up Accuracy using an Altitude Surveillance System
1994 Volume 1994 Issue 80 Pages 1-17
Details
1994 Volume 1994 Issue 80 Pages 1-17
This paper presents the statistical results of the aircraft SSR Mode-C altitude keeping accuracy using an altitude suveillance system (ASS) which was developed by the Electronic Navigation Research Institute from 1988 to 1990.
Because of a steady increase of air traffic delays in recent years, ICAO started to consider the reduction of the vertical separation from 2,000ft to 1,000ft between FL 290 and FL 410 for increasing cruise levels. Based on the collision risk assessment, ICAO RGCSP concluded in 1988 that the application of a 1,000ft vertical separation minimum was technically feasible if the air system perfomance is monitored. This ASS was developed to realize a concept of the monitoring system subject to this conclusion.
SSR data of 40,000 flight hours were processed and checked by the ASS and then the assigned altitude deviations (AAD) were detected and stored in a database in 1991. This AAD database was statistically analyzed in 1992. The average AAD was-2.1ft and the standard deviation was 47.9ft. The most influential factor to AAD was the aircraft type, the next factor was the airline operation. The difference of cruising altitudes was the least significant factor.
