VTS has two main factors; service water and management level which have several elements respectively. As the measures to quantify these elements which are sometimes quantitative, the concept of “evaluation score” is introduced. With these evaluation scores, the water factor and the factor of management for a specified VTS can be characterized as the sum of evaluation scores of each element with which “WATER INDEX” and “MANAGEMENT INDEX” can be defined.

Analysis is made on relation between WATER INDEX and MANAGEMENT INDEX. The results indicate that MANAGEMENT INDEX is considerably dependent on WATER INDEX.

Airport Surface Surveillance System (ASSS) is being developed at Electronic Navigation Research Institute (ENRI). ASSS can display a digital target that carries a data block consisting of aircraft call sign, aircraft type and other aircraft information on ASDE display by automatically detecting targets from ASDE raw video signal. It is necessary to measure and analyze quantitatively ASDE signal to improve the performance of target detection and tracking.

We made the measurement of ASDE signal reflected by aircraft at Sendai airport using a prototype radar signal recorder which can store ASDE signal into a magnetic optical disk as digital signals. As a result of the ASDE signal analysis, following things were quantitatively revealed:

1) On LIN-signal output from the linear amplifier of ASDE, the reflected signal of aircraft has very high strength compared with that of runway or taxi way,

2) while on LOG-signal output from the logarithmic amplifier of ASDE, the difference in the reflected signal strength between the above two is comparatively small, therefore the target detection is more difficult.

The ACAS II operational evaluation in Japan has been conducted as part of international cooperative activities since 1990. The results have been reported at the ICAO/SICAS (SSR Improvement and Collision Avoidance Systems) panel and the working group meetings to exchange the information among countries participating in the evaluation. Since many unnecessary alerts were detected in such evaluations, ACAS II logic was improved from version 6.0 to 6.04A and its improvement was completed in Japan before the beginning of 1995. After the evaluation, the ICAO SARPs of the ACAS II were implemented on November 9, 1995, and the official operation of ACAS II in Japan started on January 4, 1996. While the SICAS panel recommended the international standards, it asks any countries to continue operational monitoring.

This paper presents the results of ACAS II operational evaluations/monitoring from January 1, 1995 to January 31, 1996. In this period, 242 RAs were reported. The proportion of the aircraft equipped with ACAS II of major airlines in Japan is 64%. The total flight hours in this period is about 389,000 hours. The proportion that pilots followed the RA is about 80%. In 65% cases, pilots thought that the RAs were necessary and available. Pilots also gave comments that the RA was consistent with ATC in roughly 50% cases. However, in about 20% cases, pilots described that the RA was inconsistent with ATC. With regard to the altitude deviation, 70% of ACAS maneuver resulted in the altitude deviation within 700ft, but in about 15% cases, the deviation exceeded 1000ft.

These results have contributed to the ICAO/SICASP for deciding its future activities.

MMI (Man-Machine Interface System) was developed as a data link communication device for Oceanic ATC (Air Traffic Control) to evaluate its specification and functions on the assumption that a satellite data link service is introduced in Oceanic ATC fields. Prior to the development, we investigated a present air traffic controller's work load and ATC phraseologies in order to classify Oceanic ATC data link messages. In regard to the development, several modifications were conducted according to the results of evaluation tests in cooperation with air traffic controllers. This paper reports the development of MMI and results of evaluation test.