Abstract: A method and system is provided for determining leakage resistances in a bus system. The bus system has a floating DC bus connected to bus voltage source. The system also includes a pair of known resistors, each connected to the bus by a switch. The method includes with the first switch closed and the second switch open, measuring a voltage Vprtp between the bus and the ground and measuring a voltage Vnrtp between the ground and the second terminal. The method also includes, with the first switch open and the second switch closed, measuring a voltage Vprtn between the bus and the ground and measuring a voltage Vnrtn between the ground and the second terminal. The first and second leakage resistances are then calculated as a function of the known resistors and the measured voltages.

Abstract: A landing gear system for an aircraft comprising a pair of legs, each having a wheel at a distal end, a pivot point associated with each leg for allowing each leg to follow an arc-shaped path between a deployed position and a retracted position, one of the legs passing in front of the other while moving from the deployed position to the retracted position, and a linking assembly disposed between the legs for ensuring that the legs move from the deployed position to the retracted position in unison.

Abstract: A superalloy turbine blade (10) has a MCRALY bond coating (22) and a thermal barrier coating (24). The thermal barrier coating (24) comprises a plurality of alternate layers (25, 27) which have different structure to produce a plurality of interfaces (26) substantially parallel to the metallic substrate (20)/ bond coating (22) interface. These interfaces (26) provide paths of increased resistance to heat transfer to reduce thermal conductivity of thermal barrier coating (24). The structure in the alternate layers (25, 27) of the thermal barrier coating (24) is columnar (28), or segmented, to ensure that the strain tolerance of the thermal barrier coating (24) is not impaired. The columnar grains (28) in the layers (25, 27) extend substantially perpendicular to the metallic substrate (20)/ bond coating (22) interface. This enables thermal barrier coating (24) of reduced thickness and weight to be used.