Electronic standby flight instrument

• US 4,598,292 A
• Filed: 12/23/1983
• Issued: 07/01/1986
• Est. Priority Date: 12/23/1983
• Status: Expired due to Term

• Current Assignee: Grumman Aerospace Corporation (Northrop Grumman Corporation)
• Original Assignee: Grumman Aerospace Corporation (Northrop Grumman Corporation)
• Inventors: Devino, Vincent A.
• Primary Examiner(s): Caldwell, Sr., John W.
• Assistant Examiner(s): Swarthout, Brent A.
• Application Number:
  US06/564,728
• Time in Patent Office: 921 Days
• Field of Search: 364/434, 364/424, 364/433, 73/178 R, 73/178 T, 340/973-975, 340/870.13, 340/945, 340/971, 340/977-979, 320/32, 244/1 R
• US Class Current: 340/973
• CPC Class Codes: G01C 23/00 Combined instruments indicating more than one navigational value, e.g. for aircraft; Combined measuring devices for measuring two or more variables of movement, e.g. distance, speed or acceleration

Abstract

A self-contained, standby flight instrument includes sensors, processing circuitry, rechargeable power supply, voltage regulation circuitry, and display hardware arranged to provide a continuous display of aircraft airspeed, altitude, roll, pitch and heading regardless of any partial or complete failure in the primary instrumentation, an interrelated subsystem, or the electric power supply.

Claims

1. A single unit standby flight instrument for displaying turn rate, altitude, airspeed, pitch, roll, and heading of an aircraft to a pilot of the aircraft, said aircraft having an instrument panel with manual flight instrumentation, said instrument comprising

sensor means for generating a plurality of sensor signals indicative of pitot pressure, static pressure, and angular displacement rates of the aircraft;

display means for outputting display signals in a desired format;

processor means for converting the sensor signals into a purality of display signals indicative of the turn rate, altitude, airspeed, pitch, roll and heading of the aircraft, said processor means comprising sampling means for periodically sampling said sensor signals, converter means for digitizing the sampled sensor signals, multiplexing means for applying the digitized sensor signals to an input bus in a predetermined input sequence, an input register responsive to the input bus and having a tri-state output for applying said digitized sensor signals to a program bus, an output register responsive to the program bus for outputting said display signals in a multiplexed format according to a predetermined output sequence, a microprocessor for controlling data flow on the program bus and updating the output register in accordance with current values of said digitized sensor signals in the input register, and demultiplexed means responsive to said output register for routing said display signals in accordance with the predetermined output sequence to appropriate inputs of said display means;

power supply means for supplying electric power to said sensor means, processor means, and display means; and

a single instrument housing mounted within view of the pilot and enclosing said sensor means, processor means, and power supply means, said display means being mounted on said housing so as to be visible to the pilot, said housing being rigidly mounted to the aircraft and located in an area on the instrument panel close to the standard flight instrumentation and within the vision limits of the pilot, thereby providing said pilot with an emergency source of airspeed, altitude, heading, attitude, and rate of turn information in a single compact unit.

2. The device of claim 1, wherein said sensor means comprises

first and second pressure transducer means connnected, respectively, to first and second vents through the housing, the first vent communicating with a pitot tube, the second vent communicating with an unpressurized volume of static air within the aircraft, said first and second pressure transducer means generating, respectively, the pitot pressure and static pressure sensor signals;

and

at least three angular rate sensors, each generating one of the angular displacement rate sensor signals, said sensors being rigidly mounted within the housing in a non-planar orientation such that the pitch, roll, and heading of the aircraft at a given time may be computed by continuously monitoring the angular displacement rate sensor signals.

3. The device of claim 1, wherein said display means comprises a liquid crystal display.

4. The device of claim 1, wherein said sensor means, processor means and display means are electrically powered electronic components and said power supply means comprises a battery, first voltage regulator means for charging said battery from an electrical system in the aircraft, and second voltage regulator means responsive to said battery for deriving supply voltage to said sensor means, said processor means and said display means upon failure of said electrical system.