Using Broadcast Wind Observations to Update the Optimal Descent Trajectory in Real-Time

Abstract

The ability to meet a controlled time of arrival during a continuous descent operation will enable environmentally friendly and fuel efficient descent operations while simultaneously maintaining airport throughput. However, if the wind forecast used to compute the initial trajectory plan is not accurate enough, the guidance system will need to correct time deviations from the plan during the execution of the descent. Previous work proposed an on-board guidance strategy based on model predictive control, which repeatedly updates the trajectory plan in real-time from the current aircraft state and for the remainder of the descent. However, the wind conditions downstream, at altitudes not explored yet, were difficult to predict due to the lack of data. This paper shows the potential benefits of using wind observations, broadcast by nearby aircraft, to reconstruct the wind profile downstream. The wind profile in the trajectory optimization problem is modeled as a spline, which control points are updated to fit the observations before re-planning the trajectory. Results from simulations using realistic wind data show that the performance of model predictive control significantly improves when including up-to-date wind observations, in terms of time and energy errors at the metering fix and fuel consumption.

Wind velocity field estimation from aircraft derived data using Gaussian process regression

“…Multiple random factors, such as uncertainty on weather conditions, mainly wind and storms, diminish precision, which results in deviations from the reference trajectory. Thus, to improve trajectory predictability, precise wind information is necessary [ 6 , 7 ].…”

On the Estimation of Vector Wind Profiles Using Aircraft-Derived Data and Gaussian Process Regression

“…There are several ongoing projects with the aim of satisfying the ATM requirements through the incorporation of new emerging technologies, such as the Single European Sky ATM Research (SESAR) [5]. Wind profiles are used in continuous climb and descent operations, for instance, optimal profile descent, time of arrival control, or spacing [6][7][8]. Moreover, wind information is introduced to the Flight Management System (FMS) to perform trajectory parameters predictions, such as fuel and time.…”

“…The data refresh rate is within tenths of a second [13]. As a result, aircraft-derived data has lately been used in practical ATM studies [6,8,14]. It is expected that the availability of meteorological airborne data will improve in the future.…”

“…Surveillance-derived wind information has shown a favourable impact on the ATM framework. Aircraft wind data were utilized to recreate the wind profile using B-splines in [6], which was then used to optimally update aircraft descent trajectories in real time. In [22], wind uncertainty was represented using a statistical model that included the correlation of four different sources of uncertainty and a filter to describe the evolution of wind uncertainty over time, with the goal of determining the impact of wind forecast uncertainty on aircraft trajectory prediction.…”

“…In addition, a comparison with state-of-the-art KF-based methods [8,21] was carried out, showing that GPR achieves a reduction of around 35% of the estimation accuracy. Unlike previous approaches such as [6,8,21], in which only wind speed is estimated, in this paper, both north and east wind components are estimated. With regard to the nowcast of the vertical wind profile, the GPR adaptation implemented in this paper is iterative and fast, which enables data assimilation.…”