Enhanced wake vortex decay in ground proximity triggered by plate lines
Aircraft Engineering and Aerospace Technology
ISSN: 0002-2667
Article publication date: 7 March 2016
Abstract
Purpose
From pilot reports, field measurements and numerical simulations, it is known that wake vortices may persist within the glide path in ground proximity, leading to an increased encounter risk. This paper aims to investigate wake vortex behaviour during final approach and landing to understand why landings can be safe nevertheless. Further, it is investigated whether and to which extent the installation of plate lines beyond the runway tails may further accelerate wake vortex decay and thus improve safety by reducing the number of wake vortex encounters.
Design/methodology/approach
A hybrid numerical simulation approach is used to investigate vortex evolution from roll-up until final decay during the landing manoeuvre. The simulations are complemented by field measurement data accomplished at Munich Airport and at Special Airport Oberpfaffenhofen.
Findings
During touchdown, the so-called end effects trigger pressure disturbances and helical vortex structures that appear to ensure vortex decay rates in ground proximity needed to guarantee the required safety targets of aviation. Light detection and ranging (LIDAR) measurements indicate that vortex decay indeed can be accelerated by a plate line installed on the ground surface. The lifetime of the most safety relevant, long-lived and strongest vortices can be reduced by one-third.
Practical implications
The installation of plate lines beyond the runway tails may improve safety by reducing the number of wake vortex encounters and increase the efficiency of wake vortex advisory systems.
Originality/value
The novel numerical simulation technique and the acquired insights into the wake vortex phenomena occurring during landing as well as the demonstration of the functionality of the patented plate line provide high originality and value for both science and operational application.
Keywords
Acknowledgements
The work presented here was funded by the DLR projects Wetter & Fliegen and Wetteroptimierter Luftverkehr. The authors greatly acknowledge the excellent support of the teams from DFS Deutsche Flugsicherung GmbH, Flughafen München GmbH and METEK GmbH during the WakeMUC campaign. They also are grateful for the essential help and contributions of numerous colleagues from the Institute of Atmospheric Physics, DLR Flight Experiments, Special Airport Oberpfaffenhofen, German Remote Sensing Data Center, V.E. Zuev Institute of Atmospheric Optices, Lange Special Effects before, during and after the WakeOP campaign.
Citation
Holzäpfel, F., Stephan, A., Heel, T. and Körner, S. (2016), "Enhanced wake vortex decay in ground proximity triggered by plate lines", Aircraft Engineering and Aerospace Technology, Vol. 88 No. 2, pp. 206-214. https://doi.org/10.1108/AEAT-02-2015-0045
Publisher
:Emerald Group Publishing Limited
Copyright © 2016, Emerald Group Publishing Limited