Method of and system for avoiding collisions between aircraft

Claim 1

A method of avoiding collision between aircraft carrying navigational equipment for the periodic transmission, during a recurrent time slot individually allotted to each aircraft in a given area, of data relating to altitude, course and speed of the respective aircraft and for plotting from received data the flight paths of nearby aircraft, comprising the steps of: monitoring aboard a given aircraft the flight paths of other aircraft communicating with said given aircraft; upon detecting aboard said given aircraft a presumed flight path of another aircraft crossing that of said given aircraft with a minimum closing time less than a predetermined safety threshold, initiating a direct exchange of messages at an accelerated rate between said given aircraft and said other aircraft; determining aboard said given aircraft, from said direct exchange, the distance D of said aircraft from said given aircraft and the variation ΔD of said distance D from one exchange cycle to the next; calculating aboard said given aircraft a passing distance s from the parameters D and ΔD; and taking collision-avoiding measures upon said passing distance s having less than a predetermined magnitude.

Claim 2

A method of avoiding collision between aircraft carrying navigational equipment for the periodic transmission, during a recurrent time slot individually allotted to each aircraft in a given area, of data relating to altitude, course and speed of the respective aircraft and for plotting from received data the flight paths of nearby aircraft, comprising the steps of: monitoring aboard a given aircraft the flight paths of other aircraft communicating with said given aircraft; upon detecting aboard said given aircraft a presumed flight path of another aircraft crossing that of said given aircraft with a minimum closing time less than a predetermined safety threshold, initiating a direct exchange of messages at an accelerated rate between said given aircraft and said other aircraft; determining aboard said given aircraft, from said direct exchange, the distance D of said aircraft from said given aircraft and the variation ΔD of said distance D from one exchange cycle to the next; calculating aboard said given aircraft a passing distance s from the parameters D and ΔD; and taking collision-avoiding measures upon said passing distance s having less than a predetermined magnitude.

Claim 7

A system for avoiding collision between aircraft carrying navigational equipment for the periodic transmission, during a recurrent time slot individually alloted to each aircraft in a given aircraft, of data relating to altitude, course and speed of the respective aircraft and for plotting from received data the flight paths of nearby aircraft, comprising: message-analyzing means aboard a given aircraft for determining, from data transmitted by nearby aircraft, the presence of another aircraft on a possible collision course with said given aircraft; calculating means connected to said message-analyzing means for computing a minimum closing time between said given aircraft and said other aircraft; switchover means controlled by said calculating means for initiating a direct exchange of messages at an accelerated rate between said given aircraft and said other aircraft, upon detection of a minimum closing time less than a predetermined safety threshold; arithmetic means connectable by said switchover means to said message-analyzing means for ascertaining the relative distance of said given and other aircraft from said direct exchange and determining a passing distance from said relative distance and its variation with time; and alarm means triggerable by said arithmetic means upon said passing distance falling short of a predetermined magnitude for alerting the crew of said given aircraft to the need for collision-avoiding measures.

Claim 8

A system for avoiding collision between aircraft carrying navigational equipment for the periodic transmission, during a recurrent time slot individually alloted to each aircraft in a given aircraft, of data relating to altitude, course and speed of the respective aircraft and for plotting from received data the flight paths of nearby aircraft, comprising: message-analyzing means aboard a given aircraft for determining, from data transmitted by nearby aircraft, the presence of another aircraft on a possible collision course with said given aircraft; calculating means connected to said message-analyzing means for computing a minimum closing time between said given aircraft and said other aircraft; switchover means controlled by said calculating means for initiating a direct exchange of messages at an accelerated rate between said given aircraft and said other aircraft, upon detection of a minimum closing time less than a predetermined safety threshold; arithmetic means connectable by said switchover means to said message-analyzing means for ascertaining the relative distance of said given and other aircraft from said direct exchange and determining a passing distance from said relative distance and its variation with time; and alarm means triggerable by said arithmetic means upon said passing distance falling short of a predetermined magnitude for alerting the crew of said given aircraft to the need for collision-avoiding measures.