It presents critical flight information to the pilot – from airspeed, altitude, and the horizon line to the flight path vector, turn/bank indicators, angle of attack and more – using text and symbols that appear on the HUD's smooth, transparent surface. In military aircraft, the HUD also often includes a variety of targeting, weapon sensor, firing status, and other pertinent information.

The purpose of the head-up display is to make it as easy as possible for pilots to see and absorb their necessary flight or mission details while allowing them to remain "head-up and eyes-out" instead of looking down or away from what is occurring in the sky before them. This is not only safer for pilots and their crews, but also significantly increases their situational awareness and reduces pilot fatigue.

Initial concepts for HUDs were drafted at the height of World War II as a solution for pilots struggling to locate their targets in hostile skies, relying solely on verbal instructions. It wasn't until HUDs were developed that pilots were able to access information hands-free, with their head positioned up and forward; these HUDs would have been powered by conventional cathode tube technology. Today's more advanced systems see the introduction of advanced digital display drives – greatly increasing the performance and reliability of the display, whilst reducing overall weight.


This information page is provided as a service to our readers by BAE Systems, Inc., a U.S.-based world leader in aerospace, defense, power, and intelligence solutions. Learn more about us here.

Space Products

Electronic Systems

Learn more about our products and services.
Read more