Modeling ground-to-air ranging errors using a local elevation mask

Abstract

Continuous Descent Operations (CDO) with Controlled Times of Arrival (CTA) at one or several metering fixes could enable environmentally friendly procedures without compromising airspace capacity. Extending the current capabilities of state-of-the-art Flight Management Systems (FMS), the Time and Energy Managed Operations (TEMO) concept is able to generate optimal descent trajectories with an improved planning and guidance strategy to meet CTA. The primary aim of this paper is to compare the performances of TEMO (in terms of fuel consumption and time error) with respect to a typical FMS, that is an FMS without re-planning mechanism during descent based on time or altitude errors. The comparison is performed through simulation, using an A320-alike model and considering several scenarios in presence of CTA and wind uncertainties. Results show that TEMO is capable of guiding the aircraft along the optimal trajectory still complying with a CTA, even in presence of wind prediction errors. For a same scenario, a typical FMS without re-planning capabilities or tactical time-error nulling mechanism would miss the CTA in most cases.