Abstract:
An apparatus and method for displaying weather and other hazard information to a pilot with additional content which helps a pilot avoid no-fly-zones and to prepare a new flight path through a group of widely scattered thunderstorms. The display shows a no-fly-zone around the storm and the no-fly-zone is depicted differently, depending upon variables, such as distance from the aircraft, velocity of the storm being tracked and others.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to avionics, and more particularly relates to hazard avoidance systems, and even more particularly relates to electronically providing a flight crew member with information relating to “no-fly zones” (NFZs), around dynamic hazards. 
     BACKGROUND OF THE INVENTION 
     In the past, designers of avionics displays and hazard avoidance systems have endeavored to achieve a reduction in pilot workload and/or an increase in safety of flight. One area of concern has been the avoidance of weather hazards along a flight path. Pilots have, in the past, received weather reports from ground-based weather services via data link, etc. These reports have typically been textual reports describing areas of predicted severe weather. 
     While these data-linked textual reports of predicted areas of severe weather have clear advantages, they also have significant drawbacks. 
     The cockpit can become, at times, a very busy place. For example, during times when weather forces a deviation from a predetermined flight plan, a pilot is often quite busy in avoiding the storm and determining a new flight plan. These problems are compounded when the storm being avoided is part of a widely scattered group of thunderstorms. The motion of the storms and the aircraft add complexity to the flight planning procedure. Avoiding a nearby storm may put the pilot on a new path, which could intercept one or more additional storms. 
     Consequently, there exists a need for improved methods and apparatuses for providing and displaying information to a flight crew member regarding predicted future dynamic hazards and their geographic limits. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an improved means for assisting a pilot with avoiding a group of dynamic hazards. 
     It is a feature of the present invention to utilize an improved weather radar display with NFZs shown disposed about hazard areas. 
     It is an advantage of the present invention to provide a representation of areas to avoid which are very quickly discernable to a busy pilot. 
     It is another feature of the present invention to include a representation of a predicted or future location of a storm cell and an avoidance zone about the predicted location of the storm. 
     It is another advantage of the present invention to provide for increased ability to develop a safe flight path through a group of storm cells. 
     It is yet another feature of the present invention to include variably sized NFZs, where the size of the NFZ is made larger as the radial distance between the hazard and the position of the aircraft increases. 
     It is yet another advantage of the present invention to provide for the capability of reducing pilot workloads at critical times, by permitting the pilot to better understand where storm cells may be at varying times in the future so as to avoid unwanted future interception. 
     It is still another feature of the present invention to provide a computer-generated display and autopilot controlled flight path through a group of storm cells. 
     It is still another advantage of the present invention to further reduce the pilot&#39;s workload by removing or reducing the effort required to determine a new flight path through a group of storm cells. 
     The present invention is an apparatus and method for aiding a flight crew member with navigating an aircraft through a group of storm cells, which apparatus and method are designed to satisfy the aforementioned needs, provide the previously stated objects, include the above-listed features, and achieve the already articulated advantages. The present invention is carried out in a “pilot speculation-less” manner in a sense that the undesirable levels of speculation by a pilot in determining current and prospective unsafe areas in which not to fly an aircraft, has been greatly reduced. 
     Accordingly, the present invention is a multi-mode weather radar/FMS/multi-function display, together, in some applications, with an autopilot system which simultaneously display NFZs for current dynamic hazards and/or provides a graphic representation of future fixed and variably sized NFZs for dynamic hazards located at variable ranges, as well as providing computer-generated flight paths and aircraft control along those flight paths. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention may be more fully understood by reading the following description of the preferred embodiments of the invention, in conjunction with the appended drawing wherein: 
     FIG. 1 is a simplified representation of a display of the present invention, wherein several storm cells are shown with NFZs around them. The dashed lines refer to projected locations of the storm cell and the projected location of the NFZs. 
     FIG. 2 is a simplified representation of an alternate display mode of the present invention, wherein the storm cells are provided with a velocity vector and a variably sized NFZ. 
     FIG. 3 is a simplified block diagram view of a system of the present invention. 
    
    
     DETAILED DESCRIPTION 
     Now referring to the drawings wherein like numerals refer to like matter throughout, there is shown in FIG. 1 a display of the present invention, generally designated  100 , having an aircraft  102  shown with a group of concentric iso-range lines  104 . The display  100  is shown depicting a first storm cell current location  110  with a first storm cell current NFZ  112  disposed about it. First storm cell current NFZ  112  can be configured in many ways, including a polygon, an ellipse, a circle (ellipse with co-located foci) or other shapes. The NFZ will preferably be drawn with at least a 20-nautical mile (NM) buffer around the current location of the storm. In practice, the width of the avoidance zone varies with altitude, and to some extent with airline. Also, the avoidance zone can vary with height of storm: if a storm top is above the tropopause, flight crews avoid the storm by greater distances. Weather data has shown that there is probably good reason to give wide berth to very intense storms. A buffer of 15 NM is the rule of some U.S. airlines for flight above 30,000 ft. A preferred embodiment of the present invention may dictate a fixed buffer zone based in part on characteristics of the weather radar, and it could be 20 NM from the yellow (30 dBZ) contour of the storm. The first storm cell current location  110  is identified by the system of the present invention as being a storm cell to be tracked. It is given a temporary identification, and its movement is tracked over time so that predictions of future locations can be accomplished. 
     Second storm cell current location  120  is shown with a second storm cell current NFZ  122  disposed about it. Similarly, third storm cell current location  130  and fourth storm cell current location  140  are shown having third storm cell current NFZ  132  and fourth storm cell current NFZ  142 , respectively, disposed thereabout. FIG. 1, with first storm cell current NFZ  112 , second storm cell NFZ  122 , third storm cell current NFZ  132 , and fourth storm cell current NFZ  142 , all make it easier for a pilot to determine locations which are currently undesirable. By viewing the storms shown in FIG. 1, and referring only to the first storm cell current NFZ  112 , second storm cell current NFZ  122 , third storm cell current NFZ  132 , and fourth storm cell current NFZ  142  (the solid lined ellipses around the solid lined storms), a pilot might conclude that a slight deviation to the left or a bit larger deviation to the right might avoid the problem areas created by the displayed storms. However, such changes could result in an interception of either the first, the third, or the fourth storms at a future time. When the future locations of these storms are graphically provided, shown here by dashed lines, it becomes apparent that the above-mentioned maneuvers could result in an interception of a future NFZ to be associated with these storm cells. More specifically, there is shown a first storm cell future location  114  and a first storm cell future NFZ  116  about it. Similarly, there is shown a second storm cell future location  124  and a second storm cell future NFZ  126  which is further to the right. Third storm cell future location  134 , together with third storm cell future NFZ  136 , are shown having moved to the right such that they may be intercepted by a slight deviation of the flight path to the left. Fourth storm cell future location  144  and fourth storm cell future NFZ  146  depict the location of the fourth storm at a first future time period. Since fourth storm cell current NFZ  142  has a relatively longer radial distance from the aircraft  102 , it will take more time for the aircraft  102  to approach its vicinity. Consequently, a fourth storm cell more distant future NFZ  149  is shown disposed around a fourth storm cell more distant future location  148 . When fourth storm cell more distant future NFZ  149  is considered, it becomes more readily clear that a slight deviation of the flight plan to the right would not be advisable for an extended period. 
     A new flight path  150  is shown in which the aircraft  102  makes a turn to the right on leg  152  to avoid the first and the third storm cells. Then the pilot can return on leg  154  to the original flight path. This approach is particularly beneficial when accurate prediction of the velocity of storm cells is accomplished. However, storms cells can and do change direction and speed. 
     An alternate approach to displaying the trend information and the projected NFZs is depicted in FIG.  2 . This method may be preferred to the method described in FIG. 1 when the necessary confidence in predicting future storm locations is lacking. Many other arrangements are also contemplated as well. The two methods described herein are intended to be examples of the many other variations which are intended to be within the scope of the claimed invention. 
     FIG. 2 includes first storm cell current location  110 , second storm cell current location  120 , third storm cell current location  130  and fourth storm cell current location  140 ; however, the NFZs are drawn differently in FIG.  2 . First storm cell radial distance compensated NFZ  212  is shown with a vector  213  therein. Preferably, the buffer zone provided by an NFZ is larger the further a storm is from the aircraft  102 . Consequently, the separation distance b between second storm cell current location  120  and second storm cell radial distance compensated NFZ  222  is larger than the separation distance a from first storm cell current location  110  to first storm cell radial distance compensated NFZ  212 , because second storm cell current location  120  is located at a greater radial distance from the aircraft  102 . 
     Similarly, fourth storm cell radial distance compensated NFZ  242  provides for a larger buffer zone (separation distance d) than the separation distance c of the third storm cell radial distance compensated NFZ  232  because of the greater radial distance to fourth storm cell current location  140 . Vectors  213 ,  223 ,  233  and  243  may be provided to show the direction and velocity of the particular storm. The vectors may be made longer to represent their respective storm cells are traveling at a higher speed. In yet another embodiment, the NFZ could be envisioned as variable envelopes which are positioned about each of the storms, where the size, shape and orientation of the envelopes are a function of one or more of the relative locations and relative velocity of the storm with respect to the aircraft. The envelopes could have a third dimension, in which case they would be polyhedrons, or polyhedra. Size of envelopes might vary with assessed storm hazard. For example, it may be preferred to tag storm regions with a data block that contains information about maximum height, whether hail is likely, and the maximum intensity. One could advise a larger envelope for hail or storms contouring beyond 55 dBZ. 
     A computer-generated flight path  250  is shown in FIG.  2 . It suggests that the pilot make a moderate angular deviation to the right shown by leg  252 , followed by a second larger angular deviation to the right, shown by leg  254 . This second deviation occurs after the aircraft  102  reaches an area between the second, third and fourth storms. 
     When planning a deviation, the pilot might use a “direct-to” to create an alternate flight plan, direct to a waypoint. Usually the alternate flight plan is shown as a dashed line on the display. The pilot would maneuver the aircraft or manipulate the flight plan until the proposed alternate flight plan cleared all the envelopes of the storms; then the pilot would execute the proposed alternate flight plan. 
     The present invention is believed to be very beneficial as a system for use in the commercial air transport markets. As such, it could be combined with various well-known air transport avionics equipment. 
     Now referring to FIG. 3, there is shown one possible implementation of a system of the present invention generally designated  300 . The system  300  may include some or all of these components and more. For example, weather radar system  302  could be used to survey the area for severe weather, and the weather radar system  302  could be directly or indirectly coupled to flight management system  306 . The storm information could be provided by means other than the weather radar system  302 . Weather information is currently available from ground-based sources, such as NEXRAD radar facilities and other services, such as those supported by the U.S. government to track storms over the continental United States. This information could be “data linked” (sent via a data link radio) to the pilot and the on-board avionics by data link system  309 . The autopilot system  308 , data link system  309  and cockpit display  304  could all be connected as well. The interconnections between these avionics boxes are, of course, shown in a simplified manner. It should be understood that the processing of the method of the present invention could be done in any one of the above avionics boxes. It could be in a separate dedicated box, or it could be distributed among them and other avionics equipment on the aircraft. 
     In some situations, there may not be a data link system  309 ; in others, the autopilot system  308  might be omitted. In still others, the cockpit display  304  could be missing. One potential use for the present invention is to provide a serviceman with a display from which to command a fleet of unmanned aerial vehicles (UAVs). In such situations, the cockpit display  304  would obviously not be on the UAV, but at a command and control base. An autopilot system  308  and a data link system  309  would likely be included. The present invention is intended to encompass many different variations of the present invention. 
     Throughout the description the term “no-fly zone” has been used repeatedly. It should be understood that the term “no-fly zone” is not necessarily an absolute prohibition. Instead, these terms should be read to include a notion of a buffer zone or a zone to be avoided, extending in some cases beyond the displayed contours of the weather hazard. 
     Throughout this description, the terms “pilot” and “flight crew” have been used. They are selected because they are believed to readily convey the present invention; however, it should be understood that other persons, other than on-board personnel, could be substituted, and dynamic hazards other than weather, such as areas of severe turbulence or a dispersing cloud of volcanic ash, could be substituted as well. It is intended that the present invention could be applicable to vessels at sea, as well as to aircraft. It is intended that the present invention and the claims below be read to include all variations of these concepts. The designs shown and described above are merely exemplary of many other designs which could be used with the present invention. 
     The hardware and software to create the displays of the present invention are either well known in the art, or could be adapted, without undue experimentation, from well-known hardware and software, by persons having ordinary skill in the art, once they have carefully reviewed the description of the present invention included herein. 
     It is thought that the method and apparatus of the present invention will be understood from the foregoing description and that it will be apparent that various changes may be made in the form, construct steps and arrangement of the parts and steps thereof, without departing from the spirit and scope of the invention or sacrificing all of their material advantages. The form herein described is merely a preferred exemplary embodiment thereof.