D-SEND PROJECT FOR LOW SONIC BOOM DESIGN TECHNOLOGY

摘要

The D-SEND project aims to demonstrate the feasibility of JAXA 's low sonic boom design concept through the balloon drop tests. The project is carried out in two phases (D-SEND#1 and D-SEND#2). The D-SENDM drop tests were conducted twice in May 2011. The two different axisymmetric bodies were dropped from the balloon at 30km altitude and the conventional N-type and the shaped sonic booms were successfully captured by microphones at multiple altitudes up to lkm. The D-SEND#2 is scheduled to be conducted in 2013 in the same way as the D-SENDttl. An unmanned experimental supersonic airplane based on the JAXA's low sonic boom design technology is newly designed. The sonic boom intensity of the airplane is designed to be almost as half as the conventional supersonic transport. The airplane autonomously flies over microphones and the shaped sonic booms are measured. In this paper, the balloon drop test method, the test bodies and the aerial sonic boom measurement system with blimps are described. Some test results of the D-SEND#1 are presented as well.