Z Specification of Gate and Apron Control Management at Airport

Abstract

Modelling of an air traffic control (ATC) system is an open issue and has become a challenging problem due to its complexity and increase of traffic at airports and in airspace. Consequently, automated ATC systems are suggested to improve efficiency ensuring the safety standards. It is reported that the number of collisions that occurred at airports surface is three times larger than in airspace. Further, it is observed that gates and aprons congestions cause significant delays at airports; hence, effective monitoring and guidance mechanisms are required to control ground air traffic. In this paper, formal procedure of managing air traffic from gate to enter in the active area of airport for taxiing is provided using Z notation. An integration of gate and apron controllers is described to manipulate the information for correct decision making and flow management. Graph theory is used for representation of airport topology and appropriate routs. In static part of the model, safety properties are described in terms of invariants over the critical data types. In dynamic model, the state space is updated by defining pre- and postconditions ensuring the safety. Formal specification is analysed using Z/Eves tool.

Calculation Clearance Between Aircraft

“…According to ICAO Annex 14, Aircraft parking position taxiline must be separated from opposite objects with distances not less than specified using the following table: Apron area is used for pre-flight activities including parking, waiting, and maintenance. As there is an association relationship between apron area and gate, hence, apron is needed to be defined as a separate entity which consists of apron identifier and its state [8].…”

Formalizing air traffic control system using agent-based Mobile Petri Nets

“…In this research paper the airspace structure has been transformed into a directed graph where nodes represent zones being controlled by a controller and linking of zones via airway segment by edges as presented in our earlier publications in [13], [15] and [14]. The abstract ATC model is introduced by identifying mobile agents like aircraft and controller.…”

“…III. ABSTRACT MODEL Our earlier publications [13], [15] and [14] have presented model of a computer-based ATC system as shown in figure 1. The controlled airspace defined by International Civil Aviation Organization (ICAO) has been modeled as a directed graph.…”