Lesson 2.4 Glass Cockpits

1. Glass cockpits, or systems of advanced avionics, are replacing the older round-dial gauges common in many training aircraft.
a. These systems vary widely but generally provide flight information such as flight progress, engine monitoring, navigation, terrain, traffic, and weather.
b. These systems are designed to decrease pilot workload, enhance situational awareness, and increase the safety margin.
c. These systems are displayed in an electronic flight display (EFD).
2. A primary flight display (PFD) integrates all flight instruments critical to safe flight on one screen. It is a type of EFD.
a. Some PFDs incorporate or overlay navigation instruments on top of primary flight instruments.
1. EXAMPLE: An ILS or VOR may be integrated with the heading indicator.
3. A multi-function display (MFD) not only shows primary instrumentation but can combine information from multiple systems on one page or screen. It is another type of EFD.
a. Moving maps provide a pictorial view of the aircraft’s location, route, airspace, and geographical features.
NOTE: A moving map should not be used as the primary navigation instrument; it should be a supplement, not a substitute, in the navigational process.
b. Onboard weather systems, including radar, may provide real-time weather.
c. Other information that could be included on MFDs include terrain and traffic avoidance, checklists, and fuel management systems.
4. An EFD utilizes an air data computer (ADC), which receives the pitot and static inputs and computes the difference between the total pressure and the static pressure.
a. It then generates the information necessary to display the airspeed, altitude, and vertical speed on the PFD.
5. The Attitude and Heading Reference System (AHRS) replaces free-spinning gyros with solid-state laser systems that are capable of flight at any attitude without tumbling.
a. The AHRS sends attitude information to the PFD in order to generate the pitch and bank information of the attitude indicator.
b. The heading information is derived from a magnetometer that senses the Earth’s lines of magnetic flux.
6. Care should be taken that reliance on glass cockpits does not negate safety. A regular scan, both visually outside and inside on backup gauges, should be combined with other means of navigation and checklists to ensure safe flight.