Electronic Flight Instrument System, also known as EFIS Aircraft is used vastly across the world by most major airlines and in smaller aircraft. As it is the flight deck display system using electronic rather than electromagnetic technology.
Earlier versions showed information using (CRT) cathode ray tubes but were later replaced to be used by both pilots in some if not all conventional flight instrumentation.
A typical Electronic Flight Instrument System EFIS Aircraft has this system which comprises of an Electronic Horizontal Situation Indicator (EHSI),(Electronic Attitude Direction Indicator (EADI)), a Primary Flight Display (PFD)and (Navigation Display) with the two displays integrated into one.
Electronic Flight Instrument System (EFIS) Aircraft flight towers prefer these systems for their pilots as it not only makes both the tower but also the pilot’s job much safer and problem foreseeable and reactions easier. Known as the glass cockpit because of the features of the display units being the most obvious. The most critical aspect of the (PFD) is that it displayed real-time actual information such as calibrated airspeed, heading, vertical speed and yaw to mention a few which is critical for flight. Low airspeed, high rate of descent which is unusual and potentially hazardous conditions alerts aircrew by the PFD by changing colours or shape of the display or audio alerts to increase situational awareness
The EFIS control panels that enter data, display mode and range is be provided to the pilot by having to only have to enter the selection once through the data buses, for example, the desired level off altitude. Once the pilot enters it once EFIS will control that altitude by repeating the instruction to the PFD and comparing it with the actual altitude whether changes occur due to natural forces, aviation faults or even automatic pilot and reacts by generating an altitude error displays and providing appropriate warnings.
The symbol generator that produces the EFIS visual display is also known as Display Electronic Units and the Display Processing Computer. This information or data input received by EFIS formatted selections, sensor signals and the pilot. Inputs from controls and sensors are checked for validity when arriving via data buses and the inputs to the display units produced by the display drivers and graphics generator are only shown once the required computations are performed.
EFIS need power-on-self-test facilities but with additional monitoring such as:
Input validation — verify that each sensor is providing valid data Data comparison — cross-check inputs from duplicated sensors
Display monitoring — detect failures within the instrument system
