Glossary Aviation TermsAll | # A B C D E F G H I J K L M N O P Q R S T U V W X Y Z There are currently 5 terms in this directory beginning with the letter H.HindBrevity code for the Mi-24 attack helicopter.Hip Brevity code for the Mi-8 and Mi-17 transport helicopters. HMD Helmet Mounted Display; similar to a HUD, except the display is attached to the pilot's helmet and displays the information in front of their eyes. HMS Helmet Mounted Sight; similar to a HMD, but only contains weapon sighting symbology. HUD Heads Up Display, an instrument normally at the top center of an aircraft's dash, used for displaying various flight and targeting symbology.