The present invention relates to avionics. Modern commercial/private aircraft, as well as older aircraft, include a myriad of instrumentation panels associated with electronic devices having controls, displays, and software applications, which are used to present information to pilots and/or copilots during flight. The electronic devices, controls, displays and applications are interfaced together to form avionics equipment within the aircraft. Pilots (where “pilot” includes copilots and any other controller of the aircraft) access one or more interface devices of the avionics equipment prior to and during the flight. Some of this information presented monitors the status of equipment on the aircraft, while other switches and knobs are used to control functions of the aircraft such as throttles (engine speed), switches (lights, radios, etc), levers (landing gear and flaps), and controls for navigation, for example.
Avionics are important because they enable the pilot to control the aircraft, monitor and control its systems, and navigate the aircraft. Avionics systems today are manual and therefore the pilot must manually select the proper switch, knob, etc. to control a certain function in response to aircraft and environmental conditions. This action can be the result of normal activities, and is usually read from a checklist so as not to miss anything, or the result of a warning display, at which time the pilot must react accordingly. Pilot error, in the form of not knowing what to do or reacting improperly, leads to increased accident and death rates. Crashes can also result from pilots being distracted by an emergency and not maintaining control of the aircraft because they are busy troubleshooting or reacting to the problem. Additionally, many of the settings are the same on each flight, and the pilot must manually perform the same actions repeatedly. Such actions have the possibility to distract the pilot's awareness from the surrounding situation, or the state of the aircraft in flight. Such repetitions are non-value-added work, and the resultant distractions can increase the possibility of an accident.
General aviation accident statistics show that the accident rate for single pilot, non professionally flown aircraft is significantly greater than that for dual-pilot professionally flown aircraft.
Accordingly, there is a need for methods and apparatuses that reduce pilot workload and increase the performance and efficiency of the pilot's control of the aircraft through automation. This ensures both a proper response to certain emergencies, and frees up awareness for the pilot to focus on flying the aircraft rather than 1) performing routine and repetitive functions, or 2) responding manually to certain emergencies.
The present invention provides methods and apparatuses that reduce pilot workload and increase the performance and efficiency of the pilot's control of the aircraft. The present invention comprises methods and apparatuses for sensing attributes of an aircraft and efficiently communicating relevant attributes to a pilot. The invention allows a state of the aircraft to be determined, and then used to automatically control systems, configure displays, select checklists relevant to the determined state, and respond appropriately to emergencies. Embodiments of the invention can use the determined state of the aircraft to monitor and control electrical sensors and system as appropriate for the determined state; to communication information relevant to the determined state to a pilot (e.g., by displaying gauges in a manner and priority specific to the determined state); to display contextually-relevant checklists (e.g., displaying a checklist of actions necessary for an aircraft in the determined state); and to use the determined state to determine how to respond to certain emergency situations.
Embodiments of the present invention use the determined state of the aircraft to monitor and control electrical sensors and system as appropriate for the determined state; to communication information relevant to the determined state to a pilot (e.g., by displaying gauges in a manner and priority specific to the determined state); and to display contextually-relevant checklists (e.g., displaying a checklist of actions necessary for an aircraft in the determined state). For example, certain attributes can be displayed more or less prominently depending on the state of the aircraft. Embodiments of the present invention use the determined state of the aircraft to configure controllable aircraft subsystems. For example, certain engine or electrical subsystems can be automatically configured differently in different states. Additional examples of attributes and controls are presented below.
The invention is explained by using embodiment examples and corresponding drawings, which are incorporated into and form part of the specification.
The present invention provides methods and apparatuses that reduce pilot workload and increase the performance and efficiency of the pilot's control of the aircraft. Embodiments of the present invention accept inputs from various aircraft attributes. As used herein, an aircraft “attribute” includes anything that can be sensed relative to the aircraft. Examples of attributes are described below. From the aircraft attributes, the present invention determines a state of the aircraft. The “state” of the aircraft includes any of the various flight or control states encountered in flying, operating, or maintaining an aircraft. There are various terms and definitions for such states appreciated by those skilled in the art. For convenience of discussion, representative states are described below. Those skilled in the art will appreciate other terms and other definitions of states that can be accommodated in the present invention.
Embodiments of the present invention use the determined state of the aircraft to monitor and control electrical sensors and system as appropriate for the determined state; to communication information relevant to the determined state to a pilot (e.g., by displaying gauges in a manner and priority specific to the determined state); and to display contextually-relevant checklists (e.g., displaying a checklist of actions necessary for an aircraft in the determined state). For example, certain attributes can be displayed more or less prominently depending on the state of the aircraft. Embodiments of the present invention use the determined state of the aircraft to configure controllable aircraft subsystems. For example, certain engine or electrical subsystems can be automatically configured differently in different states. Additional examples of attributes and controls are presented below.
Attributes. The present invention can be responsive to a variety of aircraft attributes. Those skilled in the art will appreciate many different sensors in use in contemporary aircraft. The invention can be suitable for use in connection with any characteristic related to the aircraft. The set of attributes varies depending on the capabilities and systems of each specific aircraft model. Some examples of attributes that can be useful include those described below.
Remote acknowledge button, to indicate the pilot understands and acknowledges and alert or message from the invention.
Pressure altitude. Can be sensed via static pressure.
Calibrated Airspeed. The speed of the aircraft relative to the surrounding air; generally measured with a pitot/static pressure instrument.
Groundspeed. The speed of the aircraft while on the ground, or relative to the ground, can be a backup for airspeed; can be obtained from GPS or Loran receiver using a serial or other interface.
Cabin temperature. Can be determined from a solid state analog sensor.
Engine compartment temperature. Can be determined from a solid state analog sensor.
Bus A Volts. Measured for display to the pilot, and can be used to determine if an emergency condition exists. Can be determined from an analog to digital converter.
Bus B Volts. Measured for display to the pilot, and can be used to determine if an emergency condition exists; can be determined from an analog to digital converter.
Alt A Amps. Measured for display to the pilot, and can be used to determine if an emergency condition exists; can be determined from a solid-state current sensor, Hall effect sensor, or shunt.
Alt B Amps. Measured for display to the pilot, and can be used to determine if an emergency condition exists; can be determined from a solid-state current sensor, Hall effect sensor, or shunt.
Bat A Amps. Measured for display to the pilot, and can be used to determine if an emergency condition exists; can be determined from a solid-state current sensor, Hall effect sensor, or shunt.
Bat B Amps. Measured for display to the pilot, and can be used to determine if an emergency condition exists; can be determined from a solid-state current sensor, Hall effect sensor, or shunt.
Ambient light sensor. Allows proper illumination of panel display; can be determined from a solid state photovoltaic sensor.
Pitch trim switch (up and down). A switch can allow control of electric trim speed based on aircraft state.
Roll trim switch (left and right). A switch can allow control of electric trim speed based on aircraft state.
Pitch trim position. Allows verification and display of trim position, can be state-dependent; can be determined from trim position sensors.
Roll trim position. Allows verification and display of trim position, can be state-dependent; can be determined from trim position sensors.
BAT A temp sensor. Measured to determine if an emergency condition exists; can be determined from a solid-state temperature sensor.
BAT B temp sensor. Measured to determine if an emergency condition exists; can be determined from a solid-state temperature sensor.
Flap position switch (up or down). A switch can be used to control flaps based on the aircraft state.
Flap position. Allows verification and display of flap position, can be state-dependent; can be determined from flap position sensors.
Wireless remote. A wireless remote communication facility can allow control of selected functions during certain states.
Engine Manifold Pressure. The pressure in the engine intake manifold can be useful in determining engine performance as a condition of the aircraft state; can be measured by a pressure sensor.
Engine RPM. Rotational rate of the engine (conventionally expressed in revolutions per minute) can be useful in determining engine performance as a condition of the aircraft state; can be measured using a pulse counter.
Fuel pressure. Fluid pressure in the fuel supply to the engine, conventionally measured using an analog sensor.
Fuel flow sensor. Flow rate of fuel to the engine, conventionally measured with a pulse counter. Engine Oil pressure. Fluid pressure of oil in the pressurized oil portions of the engine, conventionally measured with an analog sensor.
Engine Oil Temperature. The temperature of the oil in the engine, conventionally measured with an analog sensor.
Outside Air Temperature. The temperature of the air outside the aircraft, conventionally sensed with an analog sensor.
Exhaust Gas Temperature. The temperature of the exhaust gas from the engine (piston or turbine); can be measured with an analog sensor in the exhaust manifold several inches from the exhaust valve (or turbine combustion chamber).
Cylinder Head Temperature. The temperature of each cylinder head in the engine; can be measured with an analog sensor mounted to or in the cylinder head.
Carburetor Temperature. The temperature of air in the carburetor; can be sensed with an analog sensor.
Fuel Tank Level. An indication of the amount of fuel in each individual fuel tank, conventionally sensed with an analog sensor.
State. The invention involves determination of a state of the aircraft. Aircraft are generally considered to be in one of various states, depending on the current operating environment and requirements of the aircraft. The present invention can be described for convenience using defined states; those skilled in the art will appreciate other aircraft states compatible with the present invention, other names for similar states, and embodiments of the present invention that do not require explicit naming of an aircraft state. The state can be used to configure a display so that the display space and the pilot effort observing the display are efficient. The state can also be used to determine control settings for some aircraft subsystems, determine which contextually-relevant checklist to show, and also to determine responses to emergencies. An example set of states are described below.
Preflight. An aircraft in this state is having its systems checked prior to flight.
Start. An aircraft in this state is just starting its engine(s).
Taxi (before run-up/take-off or after landing). An aircraft in this state has checked all preflight requirements, started the engine, and is taxiing to the runway; or has landed and is taxiing from the runway.
Run-up. An aircraft in this state is substantially stationary, but is exerting its engines and testing certain systems.
Takeoff/Climb. An aircraft in this state is accelerating down the runway, or has left the surface and is gaining altitude.
Cruise. An aircraft in this state has climbed to an appropriate altitude and is flying.
Landing. An aircraft in this state is approaching the surface, slowing down, or has just encountered the surface, after flight.
Shutdown. An aircraft in this state is recognizes that the flight is over, the aircraft is stationary, and that the engine is turned off.
Maneuver. An aircraft in this state may be in any phase of flight, but will not automatically switch to another state, during times when the aircraft is performing maneuvers.
Maintenance. An aircraft in this state allows diagnostics and other maintenance tasks to be performed.
Programming. An aircraft in this state allows the system to be programmed, for example for installation of upgrades or new functionality.
Direct Pilot Input. Direct pilot input can be accommodated in various ways. As an example, discrete switches can allow the pilot to override certain functions which are programmed by the aircraft operator. As another example, the pilot can select the state of a function using a user interface (e.g., a combination of display and knobs) on the device. As another example, a pilot can provide input to the system using a wireless remote control interface.
Control. The state of the aircraft and the attributes can allow the apparatus to automatically engage, or suggest for pilot confirmation, control of certain aircraft subsystems. Direct pilot input can be incorporated to allow confirmation of control suggestion, and to allow direct pilot override or control of aircraft subsystems. Examples of subsystems that can be suitable for automated or suggested control include the following.
Flap actuator control. Control of the flap actuators, generally expressed as “flaps up” or “flaps down.” Flap actuator control can be directed by the pilot, and can be engaged or suggested if the aircraft state is preflight or shutdown and the attributes indicate no movement of the aircraft. During flight or taxi, this function is manually controlled by the pilot via a discrete switch.
Starter contactor power. Engages the starter apparatus of the aircraft engine. The starter contactor is generally a momentary on switch, that can be directly controlled by the pilot, and can be engaged or suggested if the aircraft state is preflight and the attributes indicate engine RPM=0 and groundspeed=0 and airspeed=0. The apparatus can prevent starter contactor engagement when the state is engine RPM>0.
Fuel boost pump power. Controls the fuel boost pump, where this control indicates that a power is to be supplied to the fuel boost pump. This can be directly set by the pilot, and can be engaged or suggested if the aircraft state is start, switching fuel tanks, and certain emergency states.
Pitot heater power. Controls the heater to the pitot. This can be directly engaged by the pilot, and can be engaged or suggested if the aircraft state is any state and the attributes indicate outside air temperature is below 40 deg F.
Navigation lights power. Controls the power to the navigation lights. This can be directly engaged by the pilot, and can be engaged or suggested if the aircraft state is in flight or taxi.
Taxi light power. Controls the power to the taxi lights, and typically is configurable to off, steady on, or wig/wag (i.e., lights on alternate sides flashing). This can be directly set by the pilot, and can be engaged or suggested if the aircraft state is in taxi, takeoff or landing.
Strobe lights power. Controls the power to the strobe lights, e.g., lights used to make the aircraft more visible to other aircraft. This can be directly engaged by the pilot, and can be engaged if the aircraft state is in flight.
Beacon light power. Controls the power to the beacon lights, e.g., lights used to make the aircraft more visible to other aircraft. This can be directly engaged by the pilot, and can be engaged if the aircraft state is prior to engine start through engine shutdown.
Landing light power. Controls the power to the landing lights, e.g., lights used to illuminate the runway, and typically is configurable to off, steady on, or wig/wag (i.e., lights on alternate sides flashing). This can be directly engaged by the pilot, and can be engaged if the aircraft state is takeoff, climb/cruise, or landing mode.
Panel lights. Controls the power to the panel lights, e.g., lights used to illuminate instruments on the control panel of the aircraft. This can be directly engaged by the pilot, and can be engaged if the ambient light level falls below a pre-determined level.
Map light power. Controls the power to the map lights, e.g., lights used to illuminate a map reading area of the aircraft cockpit. This can be directly engaged by the pilot.
Autopilot power. Controls the power to an autopilot, sufficient to shut it off. This can be directly engaged by the pilot, and can be engaged as appropriate to the specific autopilot.
Cross-tie contactor power. Controls the power to the cross-tie contactor, which allows current to flow from one independent electrical bus to another. This can be directly engaged by the pilot, and can be engaged if the aircraft state is in certain emergency conditions or during engine start.
IGN 1 power or override. Controls whether a first ignition circuit is either powered or shorted to ground to disable that ignition circuit to test that circuit or magneto. This can be directly engaged by the pilot, and can be engaged if the aircraft state is start, run-up, or shutdown.
IGN 2 power or override. Controls whether a second ignition circuit is either powered or shorted to ground to disable that ignition circuit to test that circuit or magneto. This can be directly engaged by the pilot, and can be engaged if the aircraft state is start, run-up, or shutdown.
Determination of State. The state of the aircraft can be determined from its present state, from pilot input, from sensed attributes, or from a combination thereof. Various methods for determining a state are suitable for use with the present invention. As an example, the specific configuration of an aircraft can affect which attributes influence the determination of aircraft state.
The system can accommodate starting in any state. Also, there can be many more state transitions than shown in the figure; power on, reset, error detection, failure, and other conditions can contribute to state transitions. For convenience, the example will be described using only simple flight-specific attributes. The preflight state can be entered if the system determines that the aircraft power has been turned on and the engine RPM is 0. In the preflight state, the aircraft is not moving and the engine is not running.
If the pilot (or other user, for simplicity “pilot” includes any user capable of providing the indicated input or accepting the indicated output) activates a start control, then the system can transition to the start state. In the start state, the engine controls (e.g., fuel valve, fuel pump, engine ignition, etc.) are configured for starting the engine, and the engine starter is energized. Further, a contextually-relevant checklist can be displayed in this state. In the start state, the system can monitor attributes that indicate whether the engine was successfully started. If those attributes indicate that the start was not successful, the system can return to the preflight state. If those attributes indicate that the start was successful, then the system can transition to the taxi state. The taxi state can also be entered when the system determines that the engine RPM is within a defined range (e.g., 600 to 2700 RPM) and the groundspeed is less than a defined threshold (e.g., 20 kts).
In the taxi state, engine RPM and manifold pressure can be prominently displayed, and lights corresponding to taxiing can be turned on. Further, a contextually-relevant checklist can be displayed in this state. Not shown in the figure, the system can transition out of the taxi state to the preflight state if, for example, the engine RPM drops to 0. Generally, though, the aircraft will begin run-up after taxi. The system can transition to the run-up state if the attributes indicate that the engine RPM is consistently at a defined value (e.g., 1700 RPM for at least 1.5 seconds) and the aircraft groundspeed is 0. In the run-up state, if the engine slows below the defined threshold, or the groundspeed increases above 0, the system can transition back to the taxi state. While in the run-up state, a display specific to verifying the function of the propeller controls and magnetos/ignitions can be displayed, and the magnetos can be automatically individually disabled and the resultant engine performance degradation checked against allowable limits. Further, a contextually-relevant checklist can be displayed to this state.
After the run-up is complete, the taxi state can be automatically activated. From the taxi state, the pilot can manually activate the takeoff state via buttons, or the system can automatically initiate a transition into the takeoff/climb state sensed by high engine RPM and manifold pressure and increasing airspeed. Further, a contextually-relevant checklist can be displayed in this state. The system can also transition into the takeoff/climb state if it determines that the engine RPM exceeds a defined threshold (e.g., 2400 RPM) and the groundspeed exceeds a defined threshold (e.g., 20 kts). While in the takeoff/climb state, the engine RPM and manifold pressure can be prominently displayed, and certain lights are turned on, and the configuration of certain flight controls (such as trim) can be verified for the correct setting.
While in the takeoff/climb state, the pilot can manually activate the cruise state via buttons, or the system can automatically initiate a transition into the cruise state sensed by certain airspeed and engine power settings, as well as altitude level off. The system can also transition into the cruise state if it determines that the engine RPM exceeds a defined threshold (e.g., 2000 RPM) and the airspeed or groundspeed exceeds a defined threshold (e.g., 130 kts). While in the cruise state, instruments relevant to cruise flight can be displayed. Further, a contextually-relevant checklist can be displayed in this state.
The pilot can activate a landing control and initiate a transition from the cruise (or takeoff/climb) state to the landing state. Further, a contextually-relevant checklist can be displayed in this state. Also, the system can initiate a transition to the landing state if it determines that the airspeed or groundspeed is within a defined range (e.g., greater than 20 kts and less than 130 kts). While in the landing state, engine RPM and manifold pressure can be prominently displayed, and certain lights turned on, and the configuration of certain flight controls (such as trim and landing gear) can be verified for the correct setting.
The system can transition into the shutdown state when engine RPM and aircraft speed fall below thresholds. In the shutdown state, the system reverts to the preflight state.
Instrument Display Subsystem.
Conventional aircraft typically have a plurality of visual indicators, with a dedicated indicator for each attribute that might be of interest to a pilot. The present invention allows more efficient instrument display for the pilot, by allowing the information communicated to be optimized for the present state of the aircraft. The instrument panel space required, and the mental effort required by a pilot, can both be dramatically reduced. The present invention can comprise a single display, such as a flat panel display, a LCD display, an OLED display, or other programmable display. The display can comprise touch sensitive or other input technology, allowing input using the display screen. Alternatively, discrete input devices such as switches, voice input, or other input means can be used. The use of a programmable display can allow multiple information presentations, optimized based on the current state of the aircraft.
The previous descriptions generally assumed a piston engine aircraft. Those skilled in the art will appreciate adjustments to the sensors, display, and state to accommodate turbine-powered aircraft. For example, engine RPM and manifold pressure can be replaced with turbine N1% or turbine N2%.
The Features menu brings up tertiary functions such as cabin temp control and fine-tuning the panel light dimming, as examples.
A suitable display panel can comprise appropriate technology for aircraft use. A width of no more than 6.25″ can allow the system to readily fit in a standard radio rack. The system can operate in all temperature ranges expected in the aircraft cockpit environment, for example, typically −30 deg C. to +65 deg C. The screen can be daylight readable, for example with a transflective screen or transmissive screen with a brightness greater than about 500 nits. A suitable switch panel can comprise a portion of a touch sensitive display configured by the controller for pilot input. It can also comprise discrete switches mounted near the display, voice recognition, or remotely mounted switches. Switches can have high quality, gold-plated contacts for desirable reliability. The sensor interface converts analog signals from commercially-available temperature, pressure, and other analog sensors to digital signals that can be processed by the microcomputer. The controllers can be implemented using commercially available switching devices and current sensing devices, with interfaces to the microcomputer.
A suitable controller can be implemented with a conventional single board microcomputer, with discrete logic, with programmable logic, or application specific integrated circuits, or combinations thereof. A typical microprocessor is a Motorola HCS12 or comparable with built-in serial I/O and at least 256 KB of non-volatile memory. A programmable controller implementation can execute software developed using conventional programming techniques such as C programming language.
The particular sizes and equipment discussed above are cited merely to illustrate particular embodiments of the invention. It is contemplated that the use of the invention may involve components having different sizes and characteristics. It is intended that the scope of the invention be defined by the claims appended hereto.