Avionicshttp://www.jets.dk/cs/forums/27/ShowForum.aspxLooking for Avionics ?en-USCommunityServer 2.0 (Build: 60526.2668)How does HGS or HUD work ?http://www.jets.dk/cs/forums/thread/3091.aspxTue, 25 Oct 2005 06:26:51 GMTa23efcf1-9e75-4ff9-be18-cd9cb68b9485:3091SiGunson0http://www.jets.dk/cs/forums/thread/3091.aspxhttp://www.jets.dk/cs/forums/commentrss.aspx?SectionID=27&PostID=3091Please can anybody tell me how the Heads Up Display in an airliner know where the runway is situated so that it can "paint" a representation of the runway on the screen ?<br /><br />Does the HUD calculate the position from GPS data ?<br />What is involved in certifying an existing HGS system for landings in a country where the HGS is not previously certified ?<br /><br />Also can Infra Red be overlaid on older HGS systems or must one purchase an entirely new HUD system for I/R ?