Abstract:
An emergency oxygen mask, which conventional procedure will cause to be donned at the first sign of smoke, is provided with an eye protecting face plate for viewing a heads up display of flight data critical for safely maneuvering the aircraft. When the oxygen supply is started, the heads up display is activated, for example by the pilot pressing a maximum O 2  flow valve. Video data from an interface to the aircraft&#39;s ARINC 429 data bus is sent to the heads up display to provide the pilot with aircraft attitude, (pitch and bank), altitude, and heading so that the aircraft can be controlled and emergency procedures can be conducted.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates to cockpit information display systems and, more particularly to an emergency flight data display apparatus.  
         BACKGROUND OF THE INVENTION  
         [0002]    Smoke in the cockpit has been responsible for a number of aircraft accidents in which the smoke obscured critical flight reference data, prevented the flight crew from properly operating the aircraft and resulted in the loss of lives. Because of the confined conditions of the cockpit, even a minor fire producing minimal smoke can rapidly render cockpit instrument panels unreadable. Current procedures call for the flight crew to don oxygen masks at the first sign of smoke in the cockpit. However, the conventional oxygen mask functions only as a breathing apparatus for use in the absence of breathable air but offers no protection for the eyes air against blinding smoke. Although the conventional oxygen mask allows the crew to continue to breath, that may be of little benefit as the plane may crash if the pilot can not see the instrument panel to learn the aircraft&#39;s speed, attitude, heading and altitude and maneuver the aircraft to a safe landing.  
         SUMMARY OF THE INVENTION  
         [0003]    In accordance with the principles of the present invention, an emergency oxygen mask, which conventional procedure will cause to be donned at the first sign of smoke, is provided with an eye protecting face plate for viewing a heads up display of flight data critical for safely maneuvering the aircraft. When the oxygen supply is started, the heads up display is activated, for example by the pilot pressing a maximum O 2  flow valve. Video data from an interface to the aircraft&#39;s ARINC 429 data bus is sent to the heads up display of the emergency oxygen mask to provide the pilot with aircraft attitude, (pitch and bank), altitude, and heading so that the aircraft can be controlled and emergency procedures can be conducted. Two embodiments are disclosed. In a first embodiment, video data is projected on the inside of the mask faceplate from a projector mounted within the mask. In a second embodiment, the mask is provided with a liquid crystal display fold-down panel which can be viewed through the eye-protecting faceplate. Both the projector and the fold-down display receive video data from a new data processing input/output unit (DPIO) which provides an interface either to the existing aircraft ARINC data bus system or to an alternative installed data source, such as the Goodrich Aerospace GH-3000 ESIS system. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0004]    The foregoing and other objects and features of the present invention may become more apparent when the ensuing description is read together with the drawing in which:  
         [0005]    [0005]FIG. 1 shows the emergency heads up display system of the invention;  
         [0006]    [0006]FIG. 2 is a block diagram of the system data processing input/output (DPIO) unit for driving the heads up display;  
         [0007]    [0007]FIG. 3 is a view of the full face oxygen mask and face plate on which the critical flight data is projected;  
         [0008]    [0008]FIG. 4 is an enlarged view of the projector and the projected display of the mask of FIG. 3;  
         [0009]    [0009]FIG. 5 is a view of the fold-down LCD display and lens assembly attached to an eye-protecting oxygen mask; and  
         [0010]    [0010]FIG. 6 shows an alternative emergency heads up display system according to the invention. 
     
    
     DESCRIPTION  
       [0011]    A conventional emergency oxygen mask, such as those manufactured by Scott Aviation, typically connect into the aircraft&#39;s oxygen supply port for use in emergency situations. In accordance with the invention, an emergency heads-up display is incorporated in a new mask  300 , FIG. 1, which has a faceplate FP that covers and protects the entire face, especially the eyes of the wearer. Advantageously, the heads up display 300HUD may be provided either by an optical projection unit  310 , shown in detail in FIG. 4, which projects the critical flight data onto face plate FP, or by a fold down device  500 , FIG. 5, that is attached to the upper part of mask  300  and which is viewable through face plate FP. Face plate FP advantageously may be coated to provide a holographic, monochrome display of computer graphics representation of flight critical data for pilot interpretation and actions. Video data is provided to projection unit  301  or to fold down display unit  500  over wire harness  101  which connects to DPIO unit  200 , FIG. 2. Display 300HD advantageously presents a blue and brown color for sky and earth respectively and digital data is presented in white. The Projected Display, on the Special Coated oxygen mask lens, is a monochrome holographic presentation that is light green in color.  
         [0012]    In accordance with the invention, DPIO unit  200  receives existing commercial aircraft Attitude (Pitch and Roll), Heading, and Air Data (Altitude and Airspeed) from either ARINC Analog or ARINC Digital attitude and directional gyros/inertial data reference systems  102 . This flight critical data is normally provided to the flight crew on flight deck displays (not shown) for interpretation to control the aircraft. Similarly, existing aircraft air data computer  105  provides aircraft ARINC air data (airspeed and altitude) to air data busses  107  that feed the existing flight deck instruments and the DPIO unit  200  in accordance with the invention.  
         [0013]    DPIO  200  decodes and processes input data from aircraft sources such as aerospace standards ARINC 407, ARINC 429, ARINC 561, ARINC 575, ARINC 629, and Military Standard 1553 and contains video drivers to output video data that meets standards such as RS-170, RGB, VGA, NTSC, Raster Scan, and XY monochrome scans. Unit  200  is powered from the existing aircraft 28 Volt DC power distribution system or, optionally, by an independent battery. All data bus inputs are the sources for aircraft Attitude, Heading, Airspeed, and Altitude.  
         [0014]    Input ports  201 ,  202  provide buffering and data processing to interface the DPIO internal 32 bit data bus  32 DB to ARINC 407, ARINC 429, ARINC 561, ARINC 575, ARINC 629, and Military Standard 1553 data. Data bus  32 DB interfaces with internal DPIO integrated circuits for calculations, rate processing, and symbology for display. DC Discrete Input integrated circuit  203  interfaces the logic lines from the aircraft either at a DC ground (aircraft airframe) classified as a “LOW” signal potential or at a fixed 5-30 Volt DC positive logic above ground classified as a “HIGH” signal potential. The discrete data is converted to digital data for placement on to DPIO internal bus  32 DB. Analog inputs  204  are the same as DC discretes  203  except that these lines permit the positive DC Voltage to be variable from 5 to 30 Volts. The variable DC or Voltage data is converted to digital data for placement on to DPIO bus  32 DB. These lines provide various aircraft system status information so that the DPIO can change processing states when required. AC Synchro  205  is in effect similar to item  204  above except that it is AC as opposed to the DC associated with item  204 . The variable AC data is converted to digital data for placement on to DPIO bus  32 DB. These lines provide various aircraft system status information so that the DPIO can change processing states when required. CPU  207  is the Central Processing Unit responsible for DPIO bus control, data distribution, mathematical calculations, built in test functions, record keeping, data conversions, memory control and storage, symbology control, library and table references, video control, status recognition, and configuration control. Decode and Glue logic circuits  209  hold software that is programmed for data recognition, verification, and enable/inhibit logic used to control valid data on the DPIO 32 bit data bus.  211 —Flash Memory  211  is programmable non-volatile memory that hold DPIO configuration data. SRAM  213  is standard high speed volatile Random Access Memory. Symbology library integrated circuits  220  contain the software load that defines the symbology parameters for purposes of display. Display symbology includes aircraft Attitude, Heading, Airspeed, and Altitude. The library also dictates the look or appearance of the symbology on heads up display 300HD. Mezzanine Module  230  is a plug in mini circuit card that contains the Integrated circuits to process the input of Military Standard 1553 data busses as described in item  201 . SRAM  232  a reliability duplicate for item  213  described above. Display Controller integrated circuits  234  process and organize the video data for conversion. It coordinates symbology with data rates and colors to be processed by the DPIO Video drivers such as the Stroke Analog Output or the Scan Converter  236 . Stroke Analog integrated circuit  236  is a video driver for the projection display unit  310 . Similar to a television tube, stroke converter  236  processes monochrome signals, containing the aircraft data and represented as symbology, for projection onto mask display 300HD. The stroke converter sweeps the aircraft data and symbology electronically for a display sweep at a rate fast enough for visual. Scan converter integrated circuit  238  performs a similar task as item  236 , above, except the video driver is for fold-down display  500  which utilizes NTSC, RS-170, RGB, and VGA.  
         [0015]    Oxygen Mask Lens Optical Proiection Assembly (FIGS. 3, 4)  
         [0016]    The face plate FP of oxygen mask lens assembly  300  will advantageously be coated to reflect a holographic image that is projected from a small 9 mm projection device located inside the upper area of the mask.  
         [0017]    Typical specifications:  
         [0018]    a) Display: Monochrome Trans-missive Holographic  
         [0019]    b) Contrast Ratio: 80:1  
         [0020]    c) Brightness: 30 Foot Lamberts  
         [0021]    f) Interface: NTSC, PAL, RS-170, VGA, RGB, XY Monochrome  
         [0022]    g) Temperature: Operating Range −10 deg. C. to +70 Deg. C.  
         [0023]    Fold Down Lens Assembly (FIG. 5)  
         [0024]    Fold-down lens assembly  500  is hinged at  501  to the upper part of the face mask  300 . Assembly  500  includes two adjustable lenses  503 ,  505  that house two color LCDs  507 ,  509 , one for each eye. Adjustable lenses  503 ,  505  provide magnification to yield the equivalent of a 17″ computer display. Assembly  500  can be swung down for use or flipped back up for unobstructed vision through face place FP of the mask. view. When the fold-down lens assembly  500  is swung down, a microswitch  510  adjacent to hinge  501  and the terminus of cable  101  applies power to LCDs  507 ,  509  display for immediate display of aircraft attitude, heading and air-data. The LCD display advantageously employs blue and brown color for sky and earth, respectively, while digital data will be presented in white. However, colors are variable depending on customer requirements.  
         [0025]    Exemplary Specifications:  
         [0026]    a) Display: LCD 800×220 total color pixels−horizontal tv lines=400  
         [0027]    b) Contrast Ratio: 200:1  
         [0028]    c) Signal Input: NTSC, RS-170, PAL, VGA, and RGB  
         [0029]    d) Interface: Video/BNC Connector  
         [0030]    e) Power Source: 9-28 VDC  
         [0031]    f) Power Consumption: 1.5-3 Watts (brightness dependent)  
         [0032]    g) Interpupillary Range: 52-72 mm  
         [0033]    h) Temperature Operating Range: −10 Deg. C. to +70 Deg. C.  
         [0034]    i) Depressurization Tolerance to 40,000 feet  
         [0035]    Referring to FIG. 6, an alternative embodiment is shown for use with such aircraft as still have the older analog based navigation, attitude reference, and air-data systems installed. In these cases, an FM certified BF Goodrich Aerospace GH-3000 attitude, heading, and air-data reference system is available to be installed to provide the required ARINC bus data. Accordingly, connections will be made between the GH-3000 system and the DPIO. The GH-3000 system is comprised of two (2) small units that easily installs into the existing aircraft. Two advantages of having the GH-3000 installed, is that it is also a back-up reference system for the existing Primary and Secondary flight critical data reference systems adding more system safety integrity to any aircraft, and provides for an auxiliary battery electrical power source. If the GH-3000 is installed, the aircraft pitot static system shall be connected to the GH-3000 air data computer. Also, if the auxiliary battery  604  is installed, power wiring will installed between the battery and DPIO  200 . GH-3000 Attitude and Heading reference gyros  602  provide dedicated aircraft attitude (Pitch, Roll) and Heading to DPIO  200 . GH-3000 ARINC Air Data Computer  605  provides dedicated aircraft Airspeed and Altitude to DPIO  200 . Direct Current Power source  606  provides emergency electrical power in the event of normal aircraft power shut down to keep flight critical data on the Head-up Display attached to the Oxygen Mask.  
         [0036]    What has been described is deemed to be illustrative of the principles of the invention. Further and other modifications will be apparent to those skilled in the art and may be made without, however, departing from the spirit and scope of the invention.