EXECUTIVE SUMMARY:
D 2.2.2 is the contractual deliverable of FLYSAFE WP 2.2.2. It describes the final design and functionality of the Weather Information and Management System for Wake Vortices (WV WIMS) as part of the ground segment of FLYSAFE. WV WIMS aims at the FLYSAFE Target Product. It is being designed and developed for the EN-ROUTE airspace (ENR mode) and for the TMA airspace (TMA mode)
The WV WIMS receives
(i) meteorological data provided by the UK Met Office (for ENR) and the German Weather Service, DWD (for TMA),
(ii) local meteorological measurements from equipment installed at the airport (for TMA),
(iii) and ground-based WV monitoring data (for TMA).
For the FLYSAFE Target Product, the WV WIMS in mode ENR delivers to the CWP
- meteorological parameters forecast by the UK Met Office; these data can be used by the on-board Wake Encounter Prevention System (WEPS) under development in WP 2.3.1 for aircraft flying en-route.
- For the FLYSAFE Target Product, the WV WIMS in mode TMA delivers to the LWP
- meteorological parameters forecast by the German Weather Service; these data can be used by the on-board Wake Encounter Prevention System (WEPS) under development in WP 2.3.1 for aircraft flying in the TMA;
- minimum safe separations in time for ATC considering classes of aircraft between the Final Approach Fix and the Runway Threshold or – for departures – between take-off and end of initial climb phase. These separations are deduced from WV trajectories, circulation and safety areas as forecast by DLR’s wake vortex advisory system.
The functionality of the WV WIMS (mode TMA) has been demonstrated during 66 days of the FRA2006/07 campaign at Frankfurt Airport from 18 Dec 2006 until 28 Feb 2007. The system covered the glide paths of runways 25L and R from the final approach fix to the threshold (11 NM) and combined measured & forecasted meteorological data for wake prediction. The time horizon for weather predictions was 12 hours with a 10 minute increment and an update every 12 hours. For the target product of the TMA mode it is envisaged to reduce the weather forecast horizon to 2 hours, with a 10 minute increment and an update each hour. The time horizon for the WV predictions and minimum separation times for final approach is 60 minutes; updates are available every 10 minutes. From the 66 days of performance test at Frankfurt we found that
- the system ran stable - no forecast breakdowns occurred,
- aircraft separations could have been reduced in 75 % of the time compared to ICAO wake vortex separation standards,
- the predictions were correct: at least for about 1100 landings observed during 16 days no warnings of false and potentially hazardous forecasts occurred.
Fast-time simulations, which took into account the real traffic mix and operational constraints in the period of one month, revealed that with such a system at Frankfurt Airport the capacity for landing aircraft could strategically be increased by 3% (roughly 1 – 1.5 aircraft per hour) when accepting an average delay of 4 minutes per flight. On the other hand and thinking in tactical terms, the system could be used to reduce the average delay of 4 minutes by almost 50% when keeping the arrival rate constant. This approach would result in a very substantial saving of fuel and CO2 emissions.
The components of the TMA mode system also allow for prediction of wakes from departing aircraft. The evaluation of data from the respective campaign in the framework of the EU project CREDOS is still ongoing.
The ENR mode of WV WIMS consists mainly of output data routinely produced by the UK Met Office weather forecast models and, as such, needs no further evaluation. These data represent the meteorological conditions in the en-route airspace (i.e. basically everything outside the TMA) and serve as input to the onboard Wake Encounter Prevention System (WEPS) under development in WP 2.3.1. The time horizon for weather predictions is 12 hours with a 3 hour increment and an update every 6 hours for the ENR mode.
For further information please contact:
Mr. Thomas Gerz:
thomas.gerz@dlr.de