Air traffic controllers at EUROCONTROLs Maastricht Upper Area Control Centre (MUAC) are now able to access two important flight parameters that are automatically down linked from aircraft operating within their airspace: the Selected Altitude (the level that an aircraft is actually climbing or descending to) and Magnetic Heading (the actual heading being flown by the aircraft).
These two parameters are the first step in the use of Secondary Surveillance Radar (SSR) Mode Select (S) Enhanced Surveillance (EHS) at MUAC and will help to significantly improve both safety and the expeditious flow of air traffic in the upper airspace. The Selected Altitude not only provides an instant check that the aircraft is indeed climbing or descending to the level instructed by the controller, it also provides this information instantaneously to other controllers as required. It will therefore assist in further reducing level busts - incidents where an aircraft climbs or descends through the level that a controller has instructed it to maintain. To enhance the safety benefits still further, an automated warning tool that will warn controllers immediately of any discrepancy between the cleared level and the Selected Altitude will also become available later this year. The availability of the Magnetic Heading reduces the amount of radio communications between pilots and controllers, cutting down on controller workload and improving the overall situational awareness. As the Magnetic Heading is now automatically down linked from the aircraft directly to the controllers radar displays, there is no longer a requirement for controllers to request this information from pilots via voice communications. Selected Altitude and Magnetic Heading are just two of the down linked parameters made available to controllers through the introduction of Mode S Enhanced Surveillance. The use of the other down linked parameters, such as Indicated Air Speed and Mach Number is currently being validated. The availability of this information to controllers as well as other associated improvements to controller tools are already expected for the coming year.