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Atmospheric entry capsule with membrane aeroshell is drawing a good deal of research attention as a new type of reentry capsule ． In order to identify its attitude during the flight ， it is necessary tQ equip with air data sensors on its head．In our present aeroshell capsule configuration ， a hemispherical blunt nose of the capsule is mounted auhe center of conical aeroshell membrane and five pressure ports are Iocated on the blunt η ose ． During the flight ， a recirculating region will be formed near the points where the blunt nose is connected to the membrane aeroshell ． When a pressure po 質 is located in a recirculating area ， the measured pressure wiU not be sensitlve to the change ofthe attack angle ofthe reentry capsule ， which is undesirable to accurate estimation of the capsule atti田 de． For the purpose of deterrnining the preferable location of air data sensors ， numerical simulation and wind tunnel experimen 重 s were conducted ， It was revealed in the experimcnt that the pressure differences between the stagnation point and the other ports change almost linearly with respect to the attack angle ． It was also verified by the experiment and by the numerical analysis that the pressure port located at the point 45 degrees away 丘om the stagnation point is not affected by the flow recirculatlon and is preferable to the location ofair data sensors ．

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Aerocapture is expected to reduce the cost of the interplanetary exploration in the future because it utilizes aerodynamic drag to decelerate the vehicle rather than fuel-costly chemical propulsion. However, aerocapture mission involves lots of complicated difficulties such as quite narrow entry path angle, excess aerodynamic heating, aerodynamic load, and various uncertainties. It requires high levels of control technique and aerodynamic characteristics prediction. In this paper, the results of the simultaneous optimization of the flight control and aerodynamic shape for Mars aerocapture vehicle are presented. To maximize the payload mass, fuel mass for orbital transfer and TPS mass must be minimized. For this purpose, objective functions are set as follows: 1) minimize the delta-V for orbit insertion, 2) minimize the total heat load, 3) minimize both the delta-V and total heat load. Firstly, optimization was conducted only for the flight control, assuming the fixed aerodynamic shape and entry path angle. Secondary, simultaneous optimization was conducted. As a result, trade-off between delta-V and total heat load was clarified. Moreover, by executing simultaneous optimization, the guideline of designing aerocapture, which can minimize the objective function in each case 1)-3), was obtained.