Tradeoff between optimum altitude and contrail layer to ensure maximum ecological en-route performance using the enhanced trajectory prediction model (ETPM)

The Enhanced Trajectory Prediction Model (ETPM) is a logical extension of our analytic performance calculation framework “Enhanced Jet Performance Model” (EJPM), [1]. The ETPM is now capable to predict 4D trajectories of commercial or military jet aircraft with significantly increased model accuracy compared to existing performance tools such as BADA [4]. The EJPM so allows track optimization with regard to individual target functions as set out at ICAO and subsequently as SESAR Key Performance Areas (KPA’s). The presented extended model ETPM features an automated “green” en-route flight profile optimization while trading off between optimum altitude (towards maximum specific range) and minimum contrail induction (using the Schmidt Appleman criterion). This leads to maximum ecological en-route performance as radiation forces and CO2 emissions are minimized while flying under long range cruise conditions. This paper introduces both, the ETPM concept and the contrail generation model, the application and data trial for an automated 4D cruise phase optimization for given ecological objective function. It can be shown that useful compromises between environmental protection and most economic flight operations can be reached. This is based on the findings, that contrail sensitive air density layers are relatively thin.