Aircraft boundary transition warnings and auto alerting

Abstract

In combination with a Geographic Information System (GIS), 3-dimensional shapes may be used to designate or identify blocks of airspace. These shapes may be defined in many ways including lat/long, local coordinates, or FAA transmitted directions for TFRs and ADIZs. These restricted areas and zones may be modeled using suitably modified AirScene™ software from Rannoch Corporation. AirScene™ software can locate various aircraft in the vicinity of restricted airspace, determine whether the aircraft is about to enter restricted airspace, and issue a warning to the pilot of such aircraft that restricted airspace is about to be violated. Such a warning can be audible (e.g., radio communication message) or visual (e.g., graphic display or even a flashing light or text message) and is much less distracting than having a laser shining in the cockpit. Since the AirScene™ system is ground-based, ground personnel can also be advised if restricted airspace is being violated, or even about to be violated.

1 . A method of providing information indicating the relative proximity of an aircraft to restricted airspace, comprising the steps of: 
 determining position of the aircraft,    determining boundaries of restricted airspace local to the aircraft position,    generating at least one aircraft alert zone representing a region surrounding the aircraft,    determining whether the aircraft alert zone intersects boundaries of the restricted airspace, and    indicating whether an aircraft alert zone has intersected boundaries of the restricted airspace.    
     
     
         2 . The method of  claim 1 , wherein the step of determining position of the aircraft comprises the steps of: 
 receiving radio signals from the aircraft at a plurality of receiver sites,    time-stamping the radio signals when received at the receiver sites, and    determining aircraft position through multilateration of the time-stamped radio signals from the receiver sites.    
     
     
         3 . The method of  claim 1 , wherein the step of determining position of the aircraft comprises the steps of: 
 receiving altimeter data from the aircraft radio signals, and    correlating the altimeter data from the aircraft radio signals with aircraft position determined through multilateration.    
     
     
         4 . The method of  claim 1 , wherein the step of determining position of the aircraft comprises the steps of: 
 receiving radar data from an air traffic control system indicating aircraft position, and    correlating the aircraft position data from the air traffic control system with aircraft position determined through multilateration.    
     
     
         5 . The method of  claim 1 , wherein the step of determining boundaries of restricted airspace local to the aircraft position further comprises the steps of: 
 receiving restricted airspace data from a restricted airspace database, and    converting the restricted airspace data into a three-dimensional model of restricted airspace for a given region of interest.    
     
     
         6 . The method of  claim 5 , therein the restricted airspace data comprises at least one of Temporary Flight Restrictions (TFR) and Air Defense Identification Zones (ADIZ) data.  
     
     
         7 . The method of  claim 5 , wherein the step of generating at least one aircraft alert zone representing a region surrounding the aircraft further comprises the step of: 
 generating at least one alert zone surrounding the aircraft so as to provide one or more warning levels of impending intersection with a restricted airspace.    
     
     
         8 . The method of  claim 7 , wherein the at least one aircraft alert zone corresponds to the aircraft position so as to indicate when the aircraft has entered restricted airspace.  
     
     
         9 . The method of  claim 7 , wherein the step of determining whether the at least one aircraft alert zones intersects boundaries of the restricted airspace further comprises the steps of: 
 generating a three-dimensional model of the at least one aircraft alert zones, and    comparing the three-dimensional model of the at least one aircraft alert zones with the three-dimensional model of restricted airspace to determine whether any of the at least one aircraft alert zones intersect any portion of the restricted airspace.    
     
     
         10 . The method of  claim 9 , wherein the step of indicating whether any of the at least one aircraft alert zones has intersected boundaries of the restricted airspace further comprises the step of: 
 generating an alarm indicating that an aircraft alert zone has intersected the restricted airspace.    
     
     
         11 . The method of  claim 9 , wherein the step of indicating whether an aircraft alert zone has intersected boundaries of the restricted airspace further comprises the step of: 
 generating a visual display showing an aircraft alert zone and boundaries of the restricted airspace.    
     
     
         12 . The method of  claim 9 , wherein the step of indicating whether an aircraft alert zone has intersected boundaries of the restricted airspace further comprises the step of: 
 displaying on an in-cockpit display, position of the aircraft relative to boundaries of restricted airspace.    
     
     
         13 . A system of providing information means for indicating the relative proximity of an aircraft to restricted airspace, comprising: 
 means for determining position of the aircraft,    means for determining boundaries of restricted airspace local to the aircraft position,    means for generating at least one aircraft alert zone representing a region surrounding the aircraft,    means for determining whether the aircraft alert zone intersects boundaries of the restricted airspace, and    means for indicating whether an aircraft alert zone has intersected boundaries of the restricted airspace.    
     
     
         14 . The system of  claim 13 , wherein means for determining position of the aircraft comprises: 
 a plurality of receiver sites for receiving radio signals from the aircraft,    means for time-stamping the radio signals when received at the receiver sites, and    a processor for determining aircraft position through multilateration of the time-stamped radio signals from the receiver sites.    
     
     
         15 . The system of  claim 13 , wherein means for determining position of the aircraft comprises: 
 a receiver for receiving altimeter data from the aircraft radio signals, and    a processor for correlating the altimeter data from the aircraft radio signals with aircraft position determined through multilateration.    
     
     
         16 . The system of  claim 13 , wherein means for determining position of the aircraft comprises: 
 an air traffic control system for indicating aircraft position, and    a processor for correlating the aircraft position data from the air traffic control system with aircraft position determined through multilateration.    
     
     
         17 . The system of  claim 13 , wherein means for determining boundaries of restricted airspace local to the aircraft position further comprises: 
 a restricted airspace database for providing restricted airspace data, and    a processor for converting the restricted airspace data into a three-dimensional model of restricted airspace for a given region of interest.    
     
     
         18 . The system of  claim 17 , therein the restricted airspace data comprises at least one of Temporary Flight Restrictions (TFR) and Air Defense Identification Zones (ADIZ) data.  
     
     
         19 . The system of  claim 17 , wherein means for generating at least one aircraft alert zone representing a region surrounding the aircraft further comprises: 
 a processor for generating at least one alert zone surrounding the aircraft so as to provide one or more warning levels of impending intersection with a restricted airspace.    
     
     
         20 . The system of  claim 19 , wherein the at least one aircraft alert zone corresponds to the aircraft position so as to indicate when the aircraft has entered restricted airspace.  
     
     
         21 . The system of  claim 19 , wherein means for determining whether the at least one aircraft alert zones intersects boundaries of the restricted airspace further comprises: 
 a processor for generating a three-dimensional model of the at least one aircraft alert zones, and    a processor for comparing the three-dimensional model of the at least one aircraft alert zones with the three-dimensional model of restricted airspace to determine whether any of the at least one aircraft alert zones intersect any portion of the restricted airspace.    
     
     
         22 . The system of  claim 21 , wherein means for indicating whether any of the at least one aircraft alert zones has intersected boundaries of the restricted airspace further comprises: 
 an alarm for indicating that an aircraft alert zone has intersected the restricted airspace.    
     
     
         23 . The system of  claim 21 , wherein means for indicating whether an aircraft alert zone has intersected boundaries of the restricted airspace further comprises: 
 a visual display showing an aircraft alert zone and boundaries of the restricted airspace.    
     
     
         24 . The system of  claim 21 , wherein means for indicating whether an aircraft alert zone has intersected boundaries of the restricted airspace further comprises: 
 an in-cockpit display for displaying position of the aircraft relative to boundaries of restricted airspace.