Abstract:
The present invention provides a method and system for displaying critical navigational data on a primary flight display to a pilot of an aircraft. The method includes providing an image representative of weather information on a primary fight display and superimposing an image representative of a terrain warning indicator over at least part of the image representative of weather information.

Description:
RELATED APPLICATION(S) 
       [0001]    This application claims the benefit of U.S. Provisional Application Ser. No. 60/765,528, filed on Feb. 6, 2006, the entire teachings of which are incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    For the most part, Electronic Flight Information Systems (EFIS) have replaced conventional aircraft electromechanical flight instruments for displaying primary flight and navigational data to an aircraft pilot or a member of the aircrew. EFIS systems present all information necessary for a current phase of flight in a compact display. An EFIS system typically includes an engine indication and crew alerting system (EICAS) display, a multi-function display (MFD), and a primary flight display (PFD). 
         [0003]    The EICAS displays information about an aircraft&#39;s systems, such as the fuel, electrical systems, and propulsion systems. An EICAS display typically mimics conventional round (circular) gauges while supplying digital readouts of the measured parameters. 
         [0004]    The EICAS improves situational awareness by allowing aircrew members to view complex information in a graphical format. The EICAS also can alert the aircrew members to unusual or hazardous situations. For example, if an engine begins to lose oil pressure, the EICAS can sound an alert (alarm), switch the display to the page with oil system information and outline the low oil pressure data with a red box. Unlike conventional round gauges, a user can set many levels of warnings and alarms. 
         [0005]    The MFD displays navigational and weather information received from multiple systems. Typically, an MFD is “chart-centric”, where aircrew members can overlay different information over a map or chart. For example, MFD overlay information can include an aircraft&#39;s current route plan, weather information, restricted airspace information, and aircraft traffic information. The MFD can also view non-overlay types of data (e.g., current route plan) and calculated overlay types of data (e.g., the glide radius of the aircraft, given current location over terrain, winds, and aircraft speed and altitude). 
         [0006]    As with the EICAS, the MFD can display information about aircraft systems, such as fuel and electrical systems. The MFD can improve a pilot&#39;s situational awareness by changing the color or shape of the data to alert aircrew members to hazardous situations (e.g., low airspeed, high rate of decent, terrain warnings). 
         [0007]    The PFD displays all information critical to a flight, including airspeed, altitude, heading, attitude, vertical speed and yaw. The PFD improves a pilot&#39;s situational awareness by integrating this information into a single display instead of six different analog (conventional) instruments, thereby reducing the amount of time necessary to monitor the instruments. 
         [0008]    As with the MFD, the PFD increases situational awareness by alerting aircrew members to unusual or potentially hazardous conditions by changing the color or shape of the display and/or by providing audio alerts. 
       SUMMARY OF THE INVENTION 
       [0009]    Although these systems provide increased situational awareness, a need exists to combine weather information and terrain warnings onto a Navigation Display (ND), (e.g. a PFD) to provide the pilot with a navigational aide for avoiding these conditions. 
         [0010]    The present invention provides a method and system for displaying critical navigational data on a primary flight display to a pilot of an aircraft. The method includes providing an image representative of weather information on a primary fight display and superimposing an image representative of a terrain warning indicator over at least part of the image representative of weather information. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0011]    The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. 
           [0012]      FIG. 1A  is an illustration of a Primary Flight Display (PFD) showing the flight status of an aircraft on the top half and a navigation status on the bottom half, the navigation status including weather information. 
           [0013]      FIG. 1B  is an illustration of a PFD showing the flight status of an aircraft on the top half and a navigation status on the bottom half, the navigation status including terrain caution information overlaid with weather information. 
           [0014]      FIG. 1C  is an illustration of a PFD showing the flight status of an aircraft on the top half and a navigation status on the bottom half, the navigation status including terrain warning information overlaid with weather information. 
           [0015]      FIG. 2A  is an illustration of a Multi-Function Display (MFD) showing the position of an aircraft and terrain information proximate to the flight path of the aircraft. 
           [0016]      FIG. 2B  is an illustration of a MFD showing the position of an aircraft and terrain information and warnings proximate to the flight path of the aircraft. 
           [0017]      FIG. 3A  is an illustration of a MFD showing the position of an aircraft, and terrain information and weather information proximate to the flight path of the aircraft. 
           [0018]      FIG. 3B  is an illustration of a MFD showing the position of an aircraft, and terrain information and warnings and weather information proximate to the flight path of the aircraft. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]      FIG. 1A  illustrates a primary flight display (PFD)  100  utilizing the concepts of the present invention. The PFD  100  includes multiple windows for displaying mission critical information. For example, the HDG BUG  102  is a heading indicator that shows an overhead illustration of the heading of the aircraft  104  with relation to the ground. The HDG BUG  102  can include an indication of a flight path  110  of the aircraft and image  120  representative of the weather conditions/information. The flight path  110  includes flight legs  112   a ,  1122   b  . . .  112   n  bounded by waypoints  114   a ,  114   b  . . .  114   n . It should be understood that the inventive concepts can be used on any flight display. 
         [0020]    The image  120  representative of weather conditions/information provides the pilot with increased situational awareness and reduces the possibility of accidents associated with flying into severe weather conditions. Weather data/information is received from ground, satellite, weather datalink, radar and other known in-flight weather systems. The intensity of the weather is shown ranging from green to red, wherein green  122  is the lowest intensity (e.g., light rain), yellow  124  is moderate intensity (e.g. light to heavy rain), and red  126  is severe intensity (e.g., heavy rain, thunderstorms). Although the present invention uses green, yellow, and red colors as warning indicators it should be known to one skilled in the art that any colors, patterns, or symbols known in the industry can be used. 
         [0021]    As shown in  FIGS. 1B-1C , a Terrain Awareness System is used to provide the pilot with increased situational awareness and reduce the possibility of accidents associated with Controlled Flight Into Terrain (CFIT). Thus, while the aircraft is in flight, calculations are being made as to the height of the terrain in the aircraft&#39;s flight path  110 . The calculation is generated from a database of terrain heights and the aircraft&#39;s position, as determined by a GPS receiver connected to the EFIS. The calculation may also be generated by ground mapping radar or terrain sensors. If it is determined the aircraft is in danger of CFIT, a terrain warning indication  130  is superimposed over the image  120  representative of weather conditions. 
         [0022]    The terrain warning indication  130  provides a caution indicator  132   a  ( FIG. 1B ) if the aircraft is within one-minute of CFIT and a severe indicator  132   b  ( FIG. 1C ) if the aircraft is within thirty seconds of CFIT. The color associated with the caution indicator  132   a  is yellow, while the color associated with the severe indicator  132   b  is red. The terrain warning indication  130  encompasses the hazardous terrain condition within a set boundary while allowing the pilot to view the image  120  representative of weather conditions. This provides the pilot with optimal situational awareness since the pilot can make a decision based on both hazardous conditions simultaneously. 
         [0023]    The terrain warning indication  130  is shown as a waffle-type like pattern. The waffle-type like pattern includes opaque blocks representative of terrain mapping information and translucent rows and columns for allowing the pilot to view through the terrain warning indication  130 . The opaque blocks can be any shape known for displaying terrain mapping information. 
         [0024]    Although extreme weather conditions and CFIT can be hazardous to an aircraft, there is a greater probability of flying through an extreme weather condition than there is hitting an object. Thus, the image  120  representative of weather conditions is dimmed an amount in relation to the terrain warning indication  130  depending upon the proximity of the aircraft to the hazard. The image  120  representative of weather conditions, for example, can be dimmed by twenty-five percent while the aircraft is one-minute of CFIT. The image  120  representative of weather conditions, for example, can be dimmed by fifty percent while the aircraft is thirty seconds of CFIT. The image  120  representative of weather conditions is not completely turned off because it allows the pilot to make an informed decision based on both hazardous conditions simultaneously. It should be understood that variations to the time and dimming intensity can vary. 
         [0025]      FIG. 2A  illustrates a multifunction flight display (MFD)  200  utilizing the concepts as described with reference to  FIGS. 1A-1C . In one embodiment, an image  210  representative of terrain conditions within the aircraft&#39;s flight path is displayed on the MFD  200 . The height of the terrain is shown ranging from green to red, wherein green  212   a  is no danger (e.g., low terrain), yellow  212   b  is moderate danger (e.g. terrain close to height of aircraft), and red  212   c  is severe danger (e.g., terrain at or above height of aircraft). This embodiment allows the pilot to view actual terrain heights, thereby allowing the pilot to make an informed decision based on the height of the terrain. As shown in  FIG. 2B , the terrain warning indication  130  is displayed if the aircraft is in danger of CFIT. 
         [0026]      FIG. 3A  illustrates a multifunction flight display (MFD)  200  utilizing the concepts as described with reference to  FIGS. 1A-2B . In another embodiment, an image  120  representative of weather conditions and an image  210  representative of terrain conditions within the aircraft&#39;s flight path are displayed on the MFD  200 . This embodiment allows the pilot to view actual terrain heights along with weather conditions, thereby allowing the pilot to make an informed decision on both hazardous conditions simultaneously. As shown in  FIG. 3B , the terrain warning indication  130  is displayed if the aircraft is in danger of CFIT. 
         [0027]    While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.