Appendix 3
A3-7
• A significant increase in crew workload or in conditions impairing crew efficiency;
• Discomfort to the flightcrew; or
• Physical distress to passengers or cabin crew, possibly including injuries.
Menu - A list of display options available for selection.
Message - A communication that conveys an intended meaning such as an alerting or data link message.
Minor - A minor failure condition would not significantly reduce airplane safety and would involve crew actions well within their capabilities. Minor failure conditions may include:
• A slight reduction in safety margins or functional capabilities;
• A slight increase in crew workload (such as routine flight plan changes); or
• Some physical discomfort to passengers or cabin crew.
Misleading Information - Incorrect information that is not detected by the flightcrew because it appears as correct and credible information under the given circumstances.
When incorrect information is automatically detected by a monitor resulting in an indication to the flightcrew, or when the information is obviously incorrect, it is no longer considered misleading. The consequence of misleading information will depend on the nature of the information, and the given circumstances.
Mode - The functional state of a display and/or control system(s). A mode can be manually or automatically selected.
MSG-3 - Maintenance Steering Group 3. A steering group sponsored by the Airline Transportation Association whose membership includes representatives from the aviation industry and aviation regulatory authorities.
Occlusion - Visual blocking of one symbol by another, sometimes called occulting.
Partitioning - A technique for providing isolation between functionally independent software components to contain and/or isolate faults and potentially reduce the effort of the software verification process.
Appendix 3
A3-8 Pixel - A display picture element which usually consists of three (red, green, blue) sub-pixels (also called dots on a cathode ray tube).
Pixel Defect - A pixel that appears to be in a permanently on or off-state.
Primary Flight Displays - The displays used to present primary flight information.
Primary Field of View (FOV) (See Figure A3-1) - Primary Field-of-View is based on the optimum vertical and horizontal visual fields from the design eye reference point that can be viewed with eye rotation only using foveal or central vision. The description below provides an example of how this may apply to head-down displays.
Appendix 3
A3-9
With the normal line-of-sight established at 15 degrees below the horizontal plane, the values for the vertical (relative to normal line-of-sight forward of the aircraft) are +/-15 degrees optimum, with +40 degrees up and -20 degrees down maximum.
Figure A3-1 Primary Field of View
Primary Flight Information - The information whose presentation is required by §§ 25.1303(b) and 25.1333(b), and arranged by § 25.1321(b).
Primary Flight Instrument - Any display or instrument that serves as the flightcrew’s primary reference of a specific parameter of primary flight information. For example, a centrally located attitude director indicator is a primary flight instrument because it is the flightcrew’s primary reference for pitch, bank, and command steering information.
Prompt - A method of cueing the flightcrew that some input or action is required.
Appendix 3
A3-10
Required Engine Indications - The information whose presentation is required by § 25.1305.
Reversionary - The automatic or flightcrew initiated (manual) relocation of display formats or windows following a display failure.
Shading - Shading is used as:
• A coding method for separating information, change in state, give emphasis, and depth information.
• A blending method between graphic elements (map displays, synthetic vision system).
Soft Control - Display element used to manipulate, select, or de-select information (for example, menus and soft keys).
Standby Display - A backup display that is used if a primary display malfunctions.
Status information - Information about the current condition of an airplane system and its surroundings.
Symbol - A symbol is a geometric form or alpha-numeric information used to represent the state of a parameter on a display. The symbol may be further defined by its location and motion on a display.
Synthetic Vision – A computer generated image of the external topography from the perspective of the flight deck. The image is derived from aircraft attitude, high-precision navigation solution, and terrain database terrain, obstacles, and relevant cultural features.
Synthetic Vision System – An electronic means to display a synthetic vision image of the external scene topography to the flightcrew.
Texturing - A graphic, pictorial effect used to give a displayed object or graphic a specific “look” (metallic, grassy, cloudy, etc.). Texture is used:
• As a coding method for separating information, change in state, give emphasis, and depth information.
• As a blending method between graphic elements (map displays, synthetic vision system).
• To enhance similarity between a synthetic image and the real world image.
Appendix 3
A3-11 Viewing Envelope - Total volume of space where the minimum optical performance of the display is met (for example, luminance, contrast, or chromaticity). For a direct view display it is the solid angle with respect to the normal of the display image and for a HUD a threedimensional volume (Eyebox).
Time Sharing – Showing different information in the same display area at different times.
Transparency - A means of seeing a background information element through a foreground information element. Transparency can alter the color perception of both the “front” element and the “back” element.
Viewing Angle – The angle between the normal line of sight (looking straight ahead) and the line from the eye to the object being viewed. The angle can be horizontal, vertical, or a composite of those two angles.
Window (See Figure A3-2) - A rectangular physical area of the display surface. A window consists of one or more layers (see ARINC Specification 661).
Figure A3-2 – Display Format
Windowing - The technique to create windows. Segmenting a single display area into two or more independent display areas or inserting a new display area onto an existing display.
Appendix 4 A4-1
Appendix 4 Acronyms Used in This AC
AC Advisory Circular ARAC Aviation Rulemaking Advisory Committee ARP Aerospace Recommended Practices AS Aerospace Standard CCD Curser Control Device CFR Code of Federal Regulations CRT Cathode Ray Tube DEP Design Eye Position EASA European Aviation Safety Agency EUROCAE European Organization for Civil Aviation Electronics FAA Federal Aviation Administration GUI Graphical User Interface HDD Head down Display HUD Head up Display JAA Joint Airworthiness Authority LCD Liquid Crystal Display SAE SAE International (formerly Society of Automotive Engineers) TCAS Traffic Alert and Collision Avoidance System
Appendix 5
A5-1 Appendix 5 Related Regulations and Documents
General
The following related documents are provided for information purposes and are not necessarily directly referenced in this AC.
The regulations and standards listed below are applicable to particular systems or functions which may have implications on the display system characteristics even though they do not explicitly state display requirements. It is not an exhaustive list, and the references should be reviewed to ensure currency of issue status, and to check for any others that may be applicable.
1. Regulations
The full text of 14 CFR can be downloaded from the Internet at http://www.gpoaccess.gov/nara.
A paper copy may be ordered from the Government Printing Office (GPO), Superintendent of Documents, Attn: New Orders, PO Box 371954, Pittsburgh, PA 15250-7954.
The following is a list of regulations/certifications that should be considered when certifying an electronic display system:
Section
Title
§ 25.143
Controllability and Maneuverability: General
§ 25.207 Stall warning
§ 25.672 Stability augmentation and automatic and power-operated systems
§ 25.677 Trim systems
§ 25.679 Control system gust locks
§ 25.699 Lift and drag device indicator
§ 25.703 Takeoff warning system
§ 25.729 Retracting mechanism
§ 25.771 Pilot compartment
Appendix 5
A5-2 Section
Title
§ 25.773
Pilot compartment view
§ 25.777 Cockpit controls
§ 25.779
Motion and effect of cockpit controls § 25.783 Fuselage doors
§ 25.812 Emergency lighting
§ 25.841 Pressurized cabins
§ 25.854 Lavatory fire protection
§ 25.857 Cargo compartment classification
§ 25.858 Cargo or baggage compartment smoke or fire detection systems
§ 25.859 Combustion heater fire protection
§ 25.863 Flammable fluid fire protection
§ 25.901 Powerplant: Installation
§ 25.903 Engines
§ 25.904 Automatic takeoff thrust control system (ATTCS)
§ 25.1001 Fuel Jettisoning System
§ 25.1019 Oil strainer or filter
§ 25.1141 Powerplant controls: General
§ 25.1165 Engine ignition systems
§ 25.1199 Extinguishing agent containers
§ 25.1203 Fire detector system
Appendix 5
A5-3 Section
Title
§ 25.1301 Equipment: Function and installation
§ 25.1303 Flight and navigation instruments
§ 25.1305 Powerplant instruments
§ 25.1309 Equipment, systems, and installations
§ 25.1316 System lightning protection
§ 25.1321 Arrangement and visibility
§ 25.1322 Warning, caution, and advisory lights
§ 25.1323 Airspeed indicating system
§ 25.1326 Pitot heat indication systems
§ 25.1327 Magnetic direction indicator
§ 25.1329 Automatic pilot system
§ 25.1331 Instruments using a power supply
§ 25.1333 Instrument systems
§ 25.1335 Flight director systems
§ 25.1337 Powerplant instruments
§ 25.1351 Electrical Systems and Equipment: General
§ 25.1353 Electrical equipment and installations
§ 25.1355 Distribution system
§ 25.1357 Circuit protective devices
§ 25.1381 Instrument lights
Appendix 5
A5-4 Section
Title
§ 25.1383 Landing lights
§ 25.1419 Ice protection
§ 25.1431 Electronic equipment
§ 25.1435 Hydraulic systems
§ 25.1441 Oxygen equipment and supply
§ 25.1457 Cockpit voice recorders
§ 25.1459 Flight recorders
§ 25.1501 Operating Limitations and Information: General
§ 25.1523 Minimum flight crew
§ 25.1529 Instructions for Continued Airworthiness
§ 25.1541 Markings and Placards: General
§ 25.1543 Instrument markings: General
§ 25.1545 Airspeed limitation information
§ 25.1547 Magnetic direction indicator
§ 25.1549 Powerplant and auxiliary power unit instruments
§ 25.1551 Oil quantity indication
§ 25.1553 Fuel quantity indicator
§ 25.1555 Control markings
§ 25.1563 Airspeed placard
§ 25.1581 Airplane Flight Manual: General
Appendix 5
A5-5 Section
Title
§ 25.1583 Operating limitations
§ 25.1585 Operating procedures
§ 33.71 Lubrication System
§ 91.205 Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and equipment requirements
§ 91.219 Altitude alerting system or device; Turbojet powered civil airplanes
§ 91.221 Traffic alert and collision avoidance system equipment and use
§ 91.223 Terrain awareness and warning system
Part 91, Appendix A, Section 2
Required Instruments and Equipment § 121.221 Fire Precautions
§ 121.305 Flight and navigational equipment
§ 121.307 Engine instruments
§ 121.308 Lavatory fire protection
§ 121.313 Miscellaneous equipment
§ 121.323 Instruments and equipment for operations at night
§ 121.325 Instruments and equipment for operations under IFR or over-thetop
§ 121.344 Digital flight data recorders for transport category airplanes (Note:
DFDRs may be required to record Electronic display status)
§ 121.354 Terrain awareness and warning system
§ 121.356 Collision avoidance system
Appendix 5
A5-6 Section
Title
§ 121.357 Airborne weather radar equipment requirements
§ 121.358 Low-altitude windshear system equipment requirements
§ 121.360 Ground proximity warning – glideslope deviation alerting system
§ 135.149 Equipment requirements: General
§ 135.153 Ground proximity warning system
§ 135.154 Terrain awareness and warning system
§ 135.159 Equipment requirements: Carrying passengers under visual flight rules (VFR) at night or under VFR over-the-top conditions
§ 135.163 Equipment requirements: Aircraft carrying passengers under instrument flight rules (IFR)
§ 135.180 Traffic alert and collision avoidance system
Part 135, Appendix A
Additional Airworthiness Standards for 10 or More Passenger Airplanes