Florian Linke

Temporal evolution analysis of the European air transportation system: air navigation route network and airport network

Airspace is a networked space that constantly changes in order to adapt with the changing demand of air traffic. The goal of this research is to study the temporal evolution of the European air transportation system. We analyse two network layers: the air navigation route network and the airport network. For each network layer, we analyse the temporal evolution of seven centrality measures. We quantify the seasonal and weekly variation patterns by the coefficient of variation. We find that the air navigation route network is dominated by the summer/winter seasonal variations, while the airport network shows both summer/winter seasonal variations and peak/off-peak weekly patterns. From the distributions of the metrics, we find that hub nodes existing in both network layers are potentially bottlenecks of the network. Our research helps the stakeholders in air transportation systems to monitor the network performance over time and to better understand the network dynamics.

Insect Contamination Impact on Operational and Economic Effectiveness of Natural-Laminar-Flow Aircraft

The objective of this paper is to investigate the effect of insect contamination on operational and economic effectiveness of an aircraft with natural laminar flow wings designed by DLR. It is intended to show how insect debris located close to the wing leading edge influence fuel consumption on single missions as well as economic metrics like net present value. The focus will be on short-to-medium haul operations, i.e., aircraft similar to current state-of-the-art 150 passenger seated aircraft. During the analysis process tools for aircraft design, mission simulation and computation, insect contamination as well as life-cycle cost assessment will be used. The overall goal is to provide aircraft operators with a better understanding of the operational behavior of natural laminar flow aircraft under realistic operational boundary conditions and related economic implications.

Supersonic Deviations: Assessment of Sonic-Boom-Restricted Flight Routing

Overland supersonic flight bans due to the sonic boom are often said to be the reason for civil high-speed aircraft not being able to make a breakthrough. However, there is an apparent lack of studies actually quantifying the disadvantage of law-compliant supersonic flight paths versus optimum overland tracks. This paper presents a framework of city pair-specific flight routes and mission-performance simulation for accurate operational assessment of supersonic airplane designs. By application to a supposedly realistic representation of a future civil supersonic air transportation system as a use case, the impact of rerouting on flight distance, block times, and block fuels is quantified locally as well as globally. It was found that, for most of the city pairs relevant for high-value airline service, supersonic rerouting requires only small tradeoffs manifesting in detours and subsonic overland segments. Accordingly, on many itineraries, flight durations in scenarios of overland restriction were calculate...

Global Fuel Analysis of Intermediate Stop Operations on Long-Haul Routes

A global system analysis with regards to fuel efficiency and its results for an operational concept for long-range operations is presented in this paper. The net effects of an Intermediate Stop Operations (ISO) concept are shown and air transportation system related questions are discussed. It can be shown that both with existing and re-designed aircraft, the fuel saving potential is in the order of 7%–15.5% on a single mission, depending mainly on aircraft design range and the geographic location of the refueling point relative to origin and destination airports. A global analysis of all Airbus A330 and Boeing 777 flights served in 2010 is performed, defining fuel-optimum intermediate airports wherever suitable. Using only today’s aircraft would possibly yield fuel savings around 1.3%. Introducing an aircraft redesigned for 3000 nm would lead to a saving of more than 11% of the fleets total blockfuel. The optimum airport location for the ISO concept is analyzed as a function of design range. Optimum airport locations are found e.g. in India, Alaska, Siberia, or Newfoundland.

Impact of Cloud Encounter Mitigation Procedures on Operational and Economic Effectiveness of HLFC Aircraft

The objective of this paper is to investigate the effect of cloud encounter mitigation procedures on operational and economic effectiveness of aircraft with hybrid laminar flow control (HLFC) based on real-world flight routes and weather data. The objective is to evaluate whether cloud mitigation procedures are an appropriate measure to maximize the expected benefit of HLFC-technology under realistic meteorological boundary conditions. A global analysis of cloud encounter on typical airline routes has been conducted based on atmospheric data provided by the European Centre for Medium-Range Weather Forecasts. Different routing procedures have been benchmarked against each other and the most appropriate procedure for daily flight operation will be discussed. For optimizing the daily route planning of HLFC aircraft with respect to cost (direct routing with cloud Encounter and performance losses vs. re-routed flightpath) models for lateral trajectory optimization and calculation have been applied.

Optimization without limits — The world wide air traffic management project

In air traffic management, optimization is often restricted to local areas, e.g., to the vicinity of airports. Procedures around these areas stay unchanged, and effects from optimizations concerning ecological efficiency are not considered adequately. Investigating new concepts, this typically results in local gain of efficiency without proving the global benefit. The project World Wide Air Traffic Management (WW-ATM) creates a platform for optimization and validation of world-wide concepts considering feasibility, throughput, costs-and ecological efficiency, and robustness respectively fault liability. Based on different evaluation and optimization tools, complete traffic scenarios can be analyzed and improved both strategically and tactically.

Supersonic Diversions: Assessment of Great-Circle versus Sonic Boom-Restricted Flight Routing

Overland supersonic flight bans due to the sonic boom are often said to be the reason for civil high-speed aircraft not being able to make a breakthrough. However, there is an apparent lack of studies actually quantifying the disadvantage of law-compliant supersonic flight paths versus optimum overland tracks. This paper presents a framework of city pair-specific flight routes and mission performance simulation for accurate operational assessment of supersonic airplane designs. By application to a supposedly realistic representation of a future civil supersonic air transportation system as a use-case, the impact of rerouting on flight distance, block times, and block fuels is quantified locally as well as globally.