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More Electric Aircraft (MEA) or All Electric Aircraft (AEA) is intensively researched and developed all over the world to reduce total Aircraft power consumption, and thus total operation cost. In MEA or AEA development, Aerospace Research and Technologies activity are focusing the area of Electrical Power system, Flight control, Engine system, Environmental Control System and Landing Gear System.[1] We are focusing the Landing Gear Actuation System and as our 1st step we have developed prototype ELECTRO-HYDROSTATIC ACTUATOR (EHA) for Landing Gear Extension and Retraction System (LGERS) application. The prototype EHA was designed and tested to evaluate the performance, weight and reliability to apply the future Aircraft application. From our prototype model development, we have clarified the technical issues to be improved or considered in the future MEA or AEA application.

We have numerically and experimentally investigated multijunction superconducting quantum interference device (SQUID) based on intrinsic Josephson junctions (IJJs) of in order to improve the flux to voltage transfer coefficient. Numerical simulations suggest that the modulation depth of critical current decreases with an increase in the number of junctions in the stack and the SQUID consisting of few junctions will yield the best performance. The SQUIDs with in-plane loop geometry incorporating two stacks of IJJs were successfully fabricated from Bi 2 Sr 2 CaCu 2 O (BSCCO). The advantages of this layout are that the multijunction SQUID can be achieved without an increase in device size and the stack of IJJs is less affected by an applying magnetic field. At 4.2 K, the SQUIDs showed hysteretic current-voltage characteristics with typical multiple resistive branches. As the temperature was increased, the hysteresis disappeared and the SQUID showed clear periodic voltage-flux characteristics due to the quantum interference between the weakest junctions in the stacks.