No abstract

No abstract

No abstract

The increase in air traffic worldwide requires improvement of flight operational efficiency. This study aims to reveal the potential benefits, namely, savings on fuel consumption and flight time, which are expected for Japanese airspace, by statistically evaluating the operational efficiency defined by average differences of fuel consumption, flight time, and flight distance between the original and the optimized flight of domestic flights in Japan. The aircraft position and time data used in this study were obtained from Collaborative Actions for Renovation of Air Traffic Systems Open Data-the radar data released by the Japan Civil Aviation Bureau. Flight information, such as air data and fuel flow, is estimated by applying meteorological data and aircraft performance model to the position information of radar data. Each reconstructed trajectory is optimized in terms of flight fuel consumption and flight time with an assumed cost index (CI). Dynamic programming is used as the trajectory optimization method. The flight fuel consumption and flight time of the optimized flight are compared with the original values to evaluate the operational efficiency. Herein, approximately one-third of 1-day data, i.e., 1087 cases of four aircraft types, are analyzed with reasonable CI settings. Our research findings suggest that flight fuel consumption and flight distance can be saved by 312 kg and 19.7 km, respectively, on average for the object flights. Following a statistical comparison between the original and the optimized flights, it was observed that two types of features, namely, flying on a detoured path and flying with nonoptimal altitude and speed in the cruise phase, are major factors which deteriorate the total operational efficiency in terms of fuel consumption, flight time, and flight distance.

JAXA develops an unmanned technology demonstrator vehicle for low sonic boom research. The research project is called D-SEND #2 (Drop test for Simplified Evaluation of Non-symmetrically Distributed sonic boom). The autonomous demonstrator vehicle will be dropped from a high altitude balloon, and it will accelerate and glide to fly over a predetermined measurement area with a supersonic cruise condition. Trajectory optimization analysis is necessary for the design of onboard reference trajectory generation logic, which is robust against the dropping point uncertainty. An easy-to-use trajectory optimization tool using dynamic programming approach has been developed in order to generate reference trajectories in the early stage of design process. This paper introduces how the dynamic programming approach is applied to the D-SEND #2 flight trajectory optimization, and it shows numerical examples, which include the maximum and minimum range problems, and range adjustment problems.