Abstract:
An aircraft electronics system is provided that includes a radar system, a display, an embedded global positioning/inertial navigation system (EGI) and a processor. The radar system is configured to generate aircraft operational data. The display is configured to display the aircraft operational data. The EGI is configured to generate aircraft behavior components and the processor configured to override the aircraft operation data displayed on the display when at least one of the aircraft behavior components is beyond a defined limit, wherein potentially incorrect aircraft operational data affected by at least one of the aircraft behavior component is not displayed.

Description:
BACKGROUND 
   High performance aircraft, such as fighter jets, present special problems relating to the determination of flight information such as the aircrafts altitude during extreme rolls and pitches. In particular, during severe rolls and pitches of the aircraft, altimeters are prone to report an incorrect altitude of the aircraft to a pilot. The pilot will only receive valid altimeter information after the extreme roll or pitch has passed. However, a delay is encountered since the radar will have to change tracking from the incorrect altitude to the correct altitude. 
   For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a method of effectively dealing with incorrect data produced in response to a extreme maneuvers of the aircraft. 
   SUMMARY OF INVENTION 
   The above-mentioned problems of current systems are addressed by embodiments of the present invention and will be understood by reading and studying the following specification. The following summary is made by way of example and not by way of limitation. It is merely provided to aid the reader in understanding some of the aspects of the invention. 
   In one embodiment, an aircraft electronics system is provided. The system includes a radar system, a display, an embedded global positioning/inertial navigation system (EGI) and a processor. The radar system is configured to generate aircraft operational data. The display is configured to display the aircraft operational data. The EGI is configured to generate aircraft behavior components and the processor configured to override the aircraft operation data displayed on the display when at least one of the aircraft behavior components is beyond a defined limit, wherein potentially incorrect aircraft operational data affected by at least one of the aircraft behavior component is not displayed. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention can be more easily understood and further advantages and uses thereof more readily apparent, when considered in view of the detailed description and the following figures in which: 
       FIG. 1  is a block diagram of an aircraft electronic system of one embodiment of the present invention; and 
       FIG. 2  is a flow diagram illustrating one method of implementing an embodiment of the present invention. 
   

   In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the present invention. Reference characters denote like elements throughout Figures and text. 
   DETAILED DESCRIPTION 
   In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the inventions may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, mechanical and electrical changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the claims and equivalents thereof. 
   Embodiments of the present invention provide and apparatus and method for reporting not valid altimeter outputs and re-establishing correct altimeter outputs in a relatively fast manner. In particular, in embodiments of the present invention, aircraft behavior components are monitored. When a component, such as roll, exceeds a select degree parameter, the altimeter display is configured to display a message that the altimeter reading is not valid. Further in embodiments, the altimeter reading right before the select degree is exceeded is stored in memory. When the aircraft&#39;s roll component, goes below another select degree limit, roll resume is restored. At this point, altitude is tracked starting from the stored altitude in memory. This reduces a delay in generating a correct altimeter reading. 
   Referring to  FIG. 1 , one embodiment of an aircraft electronics system  100  is illustrated. In this embodiment, the aircraft electronics system  102  includes a radar system  110 , an embedded global positioning system/inertial navigation system (EGI)  104 , and aircraft processor  106 , a heads up display (HUD) display and a bi-directional bus  102 . The radar system  110  includes a controller chip  112 , a microcontroller  114  and a memory  110 . The chip controller  112  in the radar system  110  determines a radar state based in part on input attitude data from the EGI  104  and the aircraft commands from the aircraft processor  106 . The microcontroller  114  processes radar algorithms and provides radar information to the controller  112 . The memory  116  of the radar system is used to store a radar operation flight code used by the microcontroller  114 . The memory  116  is also used in embodiments to store operational behavior data of the aircraft. In one embodiment, the bus  120  is a  1553  bus  120  and the controller chip  112  is a  1553  controller chip  112 . The HUD  108  displays the operation data (flight information) of the aircraft such as the aircraft&#39;s altitude under control of the aircraft processor  106 . 
   Referring to  FIG. 2 , a flow diagram  200  of one embodiment of the present invention is illustrated. As illustrated, the process starts by generating radar information for a display ( 202 ). At least one behavior component of the aircraft is monitored ( 204 ). Examples of behavior components include but are not limited to roll, pitch and yaw. In this embodiment, a behavior component is determined if it is below a first limit ( 206 ). For example, if the behavior component is roll, a first limit will be a roll degree. The first limit roll degree is selected based on knowledge of when an extreme roll degree will affect the operational data of the aircraft such as the aircraft&#39;s altitude data. For example, if a roll of the aircraft over 60 degrees affects the accuracy of altitude data the first limit will be set for 60 degrees. If the roll of the aircraft is under 60 degrees ( 206 ), radar information (altitude) is displayed ( 210 ) and the roll is continued to be monitored at ( 204 ). If the roll of the aircraft is over 60 degrees ( 206 ), an inaccurate information message is displayed ( 208 ) so the pilot will not rely on the data. 
   In the roll example, the period of time when the roll degree is above the first limit can generally be referred to as the roll inhibitive period. The behavior component (roll in this example) is then monitored at ( 209 ). It is then determined if the roll is above a second limit ( 212 ). The second limit can be different than the first limit. For example, the second limit in the roll example may be 59.5 degrees. If the roll is above the second limit ( 212 ), the inaccurate data message is continued to be shown at ( 208 ). If the roll of the aircraft is below the second limit ( 212 ), the operational data (altitude in this example) is displayed at ( 210 ). The period of time when the roll degree is below the second limit can generally be referred to as the roll resume period. In the roll example, the altitude of the aircraft as the aircraft reaches the first limit is stored in a memory, such as memory  116  of  FIG. 110 . When the roll resume period is entered, the stored altitude is loaded into the radar system and the altitude is tracked from the stored altitude position. This reduces the time needed by the radar system to determine a current altitude. The present invention is not limited to roll behavior components and that the limits will vary depending on the behavior component. 
   The methods and techniques of the aircraft electronics system  100  described above may be implemented using digital electronic circuitry, or with a programmable processor (for example, a special-purpose processor or a general-purpose process such as a computer) firmware, software, or in combinations of them. Apparatus embodying these techniques may include appropriate input and output devices, a programmable processor, and a storage medium tangibly embodying program instructions for execution by the programmable processor. A process embodying these techniques may be performed by a programmable processor executing a program of instructions to perform desired functions by operating on input data and generating appropriate output. The techniques may advantageously be implemented in one or more programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device. Generally, a processor will receive instructions and data from a read-only memory and/or a random access memory. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM disks. Any of the foregoing may be supplemented by, or incorporated in, specially-designed application-specific integrated circuits (ASICs). 
   Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, which is calculated to achieve the same purpose, may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.