Abstract: A gas turbine engine section has a rotor carrying a plurality of blades. The blades have airfoils which define a radially outer tip. A blade outer air seal is positioned radially outwardly of the tips of the blades. The blade outer air seal is provided by at least a plurality of circumferentially spaced segments, which slide circumferentially relative to each other to adjust an inner diameter of an inner surface of the blade outer air seal segments. An actuator actuates the blade outer air seal segments to slide towards each other to control a clearance between the inner periphery of the blade outer air seal segments and the radially outer tip of the blade airfoils. A gas turbine engine is also disclosed.

Abstract: A system for managing thermal transfer in an aircraft includes a fuel stabilization unit, a fuel-air heat exchanger, and a turbine. The fuel-air heat exchanger is located downstream from the fuel stabilization unit. The fuel-air heat exchanger places deoxygenized fuel in a heat exchange relationship with compressor bleed air to produce heated deoxygenized fuel and cooled bleed air. The turbine is operationally connected to the engine compressor and receives cooled bleed air from the fuel-air heat exchanger.

Abstract: A variable vane control system for use with a gas turbine engine includes an actuator, a mechanical linkage assembly, and a vane position sensor. The gas turbine engine has a plurality of variable vanes each having an airfoil disposed in a gas flow path of the gas turbine engine. The plurality of variable vanes includes a first variable vane. The mechanical linkage assembly operably connects the actuator to at least the first variable vane. The vane position sensor is connected to one of the first variable vane or a portion of the mechanical linkage assembly proximate the first variable vane for sensing angular position of the first variable vane.

Abstract: A flutter control system for a turbomachine fan includes a plurality of fan case sensors located at a fan case of the turbomachine and configured to sense passing of blade tips of a fan of the turbomachine. A controller is operably connected to the plurality of fan case sensors. A variable fan area nozzle actuator is operably connected to the controller, such that the variable fan area nozzle actuator urges a change in fan nozzle area in response to data from the plurality of fan case sensors indicating flutter or near flutter conditions. A method of flutter control for a turbomachine fan includes sensing a blade tip passing of a plurality of fan blades. Data from a plurality of fan case sensors is compared to a threshold and a fan exit area is changed based on the comparison to dampen flutter of the plurality of fan blades.

Abstract: An example fuel system includes a fuel sensor configured to sense at least one characteristic of a fuel provided to an engine. The fuel is selected from a plurality of different fuel types. The fuel system also includes a controller that is configured to meter the fuel in response to the at least one characteristic of the fuel.

Abstract: A power probe for in-situ electron microscope viewing of electromigration in aluminum thin films has a probe holder, a detachable probe tip and, mounted on the probe tip, a quartz power distributor. A test specimen, such as an integrated circuit component, can be viewed inside the electron microscope while logic gates or other components are exercised. The probe holder is shaped to mate to a conventional electron microscope side entry port. The probe tip attaches to the end of the probe holder and extends into the electron beam path. The test specimen mounts on the power distributor which is in turn mounted inside a trough at the end of the detachable probe tip. The probe tip and power distributor include mutually aligned openings, over which the test specimen mounts, for the electron beam path.