Flight demonstration project for low‐sonic boom design technology

Abstract

Japan Aerospace Exploration Agency (JAXA) has promoted a supersonic technology research program including flight demonstration since 1997. In this program, JAXA is now planning the new flight demonstration project ‘‘Silent Supersonic Technology Demonstrator Project (S3TD).’’ One of the targets of this project is to demonstrate the low sonic boom aircraft concept to reduce sonic boom intensity by 50% as compared with conventional configuration and to modify the sonic boom signature for not only front shock boom but also the rear shock one. JAXA will develop a new flight demonstrator that is an unmanned vehicle of approximately 3 tons in weight and 13 m in length, and then JAXA will make flight trials by 2012. Now JAXA is designing the base‐line configuration, using the CAD‐based Automatic Panel Analysis System that we have developed. The shock overpressure of the S3TD base‐line configuration is estimated to be about 0.23 psf for front shock and 0.21 psf for rear shock, corresponding to about 50% intensity as compared with those of N‐wave signature estimated by the first‐cut method. The robustness of the low boom signature is also considered. The rear shock boom signature is so sensitive to flight condition that some small device is installed around the aft deck.