Abstract: An electronics enclosure for use in a gas turbine engine. The electronics enclosure including: a housing; one or more electronic devices, located within the housing, for use in controlling or monitoring the gas turbine engine; and a thermoelectric cooler configured, based upon a determination of an operational state of the gas turbine engine, to change between an active cooling mode, whereby the thermoelectric cooler is provided with power and thereby operated to cool the inside of the housing, and a passive mode, in which the thermoelectric cooler is not operated.

Abstract: There are disclosed corresponding methods, systems, controllers (26) and software for machine (10) sensor network management. Upon receiving from a node a request to join an existing network of machine sensors (25), sound waves are emitted in the vicinity of the machine (10). The emitted sound waves are sensed by the node and a corresponding signal output is generated by the node. The signal output from the node is compared with the emitted sound waves and/or a further signal output from one or more machine sensor (25) in the existing network. The node request to join the existing network is authenticated or rejected based on the comparison.