Abstract: The present invention provides an installation management system for an aircraft server. In this case, the server comprises an installation data memory for storing at least one installation data pack. When updating installation files of the installation data pack, the installation files to be updated are overwritten by respective modified installation files. These modified installation files are contained in an installation service pack which is loaded by the aircraft server.

Abstract: An apparatus includes a microwave source that produces a microwave feed beam, and a first pair of microwave sensors that each intercept and receive a portion of the microwave feed beam. The two microwave sensors are spaced apart from each other along a first-pair axis. A first phase-comparison device has as it inputs the output signals of the two microwave sensors, and as an output a first phase comparison of the first-sensor output signal and the second-sensor output signal. A first geometrical calculator has as an input the first phase comparison and as an output a geometrical relationship of the first-pair axis to an other feature. This geometrical relationship output may be used to generate a control signal that is used to alter the geometrical relationship. There may be additional microwave sensors operating in a similar manner but spaced to provide information for other geometrical axes or allow improvements in geometrical measurements.