Constrained Airspace Rerouting Planner for ACES (2008)

NASA’s Airspace Concept Evaluation System (ACES) is a non-real-time, computer simulation of local, regional, and nationwide facto rs covering aircraft operations from gate departure to gate arrival. The overarching objectiv e of ACES is to provide a flexible NAS simulation and modeling environment that can assess the impact of new NAS tools, concepts, and architectures, including those that represent a significant departure from the existing NAS operational paradigm. In this paper we present the algorithm, software implementation details and simulation results of a Constrained Air space Rerouting Planner (CARP) that was developed and implemented in ACES. CARP provides ACES users several capabilities needed to model and simulate strategic and tactical rerouting algorithms for time varying constrained regions in the en route airspace for th e purpose of studying and evaluating NextGen Concepts. I. Introduction Planning strategic and tactical re-routes around re gions of the airspace that are constrained due to p henomenon such as whether, special usage airspace restrictions or other FAA mandated closures due to equipment failure or potential threats is an active area of research. For example in Ref 1-4 several approaches for rerouting around weather cells are presented. Approaches have varied from using more traditional approaches such a those based A*(com bined with Snells law), computing shortest paths, and geo metric algorithms. In Ref 5 rerouting due to constr aints on airspace due to security and safety related events are presented. A limitation in several of these app roaches has been representation of weather cells or other constraine d airspace phenomenon as static (not time varying) polygons and the limited use of forecasted data. The rerouting p roblem is dynamic and time dependent and modeling the constrained airspace as time-varying cells and the use of forecasted data in planning re-routes can po tentially offer a more effective and efficient solution. In this paper we present the details of a dynamic r erouting algorithm, software implementation details and simulation results of a novel Constrained Airspace Rerouting Planner that was developed and implemented in NASA’s Airspace Concept Evaluation System (ACES) 6 . CARP provides ACES users several capabilities needed to model and simulate strategic and tactical rerouting algorithms for time varying constrained regions in the enroute airspace for the purpose of studying and evaluating NextGen Concepts. In addition to a discussion on the CARP algorithms, the paper also include details regardin g the software implementation of CARP in ACES, as ACES activities and plug-in. The paper also includes sim ulation results using CARP to perform rerouting due to convective weather effects for the Great Lakes region and metr ics related to average delays are computed. Operati on Network (OPSNET) data for each day in 2006 were used to find candidate days for the example scenario. The weat her scenario data is generated using the Weather Scenar io Toolbox developed at NASA Ames 7 . The paper concludes with a discussion on the limitation of the CARP and future direction for research.