Electronic Flight Instruments

First, the primary flight instruments can all be displayed simultaneously on one reasonably easy-to-read video monitor called primary flight displays (PFDs). Although you must still cross-check around the panel and on the display, more information is available in a smaller space in easier to read colors. Second, the author goes on to say that these convenient displays receive data from sensors such as magnetometers or magnetic flux valves to determine heading referenced to magnetic north. The attitude (pitch, roll and yaw) of the aircraft is sensed by the attitude heading reference systems (AHRS). The altitude, airspeed and even outside temperature values are sensed in the air data computer (ADC) and presented in the PFD on vertical scales or portions of circles. After that, there are multi-function displays (MFD) which can often display the same information as the PFD and can be used as a backup PFD. Usually the MFD is used for traffic, route selection, and weather and terrain avoidance. Finally, it is important to be very careful in the selection of the various functions and features. In the event of failures, which have a large impact on flight safety, pilot must always be ready and able to complete the flight safely using only the standby/backup instruments.