Multi-Mode Receiver (MMR), LAAS Cert., Collins GLU-925 Global Landing Unit

Black box flight test unit used in certification trials

The GLU-925 Multi-Mode Receiver (MMR) is the first certified example of an integrated navigational system that incorporates signals from multiple types of navigational and landing systems, including GPS [WAAS and LAAS], GNSS, VOR, MLS, ILS, and integrating them into a single presentation and using the combination of signals to verify the accuracy of others. This allows an air-transport aircraft to use the most adventageous form of navigation, without having to add additional equipment, regardless of where they are in the world. Different nationalities often favor different technologies, sometimes for purely political reasons. The GLU-925 marks the first time that a navigational set has been certified for LAAS capability. LAAS utilizes a GPS differential to provide precision vertical azimuth guidance during landing. This allows air-tranpsort aircraft to make "Cat III" type blind landings with significantly less infrastructure than previous ILS-based procedures. This system will allow much lower landing minimums at a far greater number of airports and will improve the the efficiency of air traffic networks.