Development of Conflict-Free Environmentally Friendly Departure Routes in a Spoke-Wheel Airspace Structure

Abstract

In a state-of-the-art major airport, like for example Munich International Airport, almost the whole arriving traffic is heavily restricted in terms of airspeed, vertical speed or cleared altitudes by Air Traffic Control (ATC) [3]. Concerning the trajectories flown by different aircraft, so-called trombones including a downwind, base leg and final are planned by the Air Traffic Controllers to make best use of the available capacity. Consequently, every approach flown by an aircraft under ATC restrictions cannot be executed at an optimum level of efficiency in terms of fuel burn or noise emissions. Likewise, the departing traffic is heavily restricted as well, for example by late climb clearances which lead to long level flights at low altitudes and consequently high noise and fuel emissions. Therefore, the German Aerospace Center / Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) developed a new airspace structure design which is called the Spoke-Wheel airspace structure [4]. In a Spoke-Wheel airspace structure, the aim is to design certain arrival and approach routes in a way, so that a continuous descent operation without a fundamental loss in capacity is possible [12]. An aircraft objected to a continuous descent arrival route will commence descent by leaving its cruising altitude and not stopping the descent until landing at the airfield. The main goal is to avoid any intermittent level-off with the benefit of causing less noise, less fuel burn and thus, less environmental damage [5]. Several projects and theses developed by the DLR [4] have discussed the topic by suggesting an airspace structure in the SpokeWheel form. One factor which has not yet been thoroughly examined is the design of departure routes in the proposed airspace with test phases at various international airports. Initially, arriving traffic is prioritized over departing traffic, making it necessary for departing traffic to level off early during climb or even plotting tremendously longer departure tracks in order to allow for continuous descent operation of other aircraft. This in turn has a negative impact in noise, fuel burn and general environmental damage. 1.2 O