Evaluation of Guidance and Control System of D–SEND#2

Release from a high-altitude balloon is a cost-effective means of achieving supersonic flight, but there have been only two prior applications of this method to aircraft flight testing. The Japanese Aerospace Exploration Agency’s D–SEND#2 flight experiment is the latest of this kind of test. Due to the one-shot nature of the experiment, it was not sufficient to guarantee the stability of the test vehicle, but it was also necessary to achieve the mission objectives on the first flight. Accordingly, we performed an inclusive pre-flight evaluation of D–SEND#2 including the flight controller and operating conditions. This approach was very effective at enhancing the probability of mission success under off-design flight conditions. The actual flight results presented in this paper demonstrate the effectiveness of this approach.