New applications of embedded systems are envisioned in the context of aeronautics. However, the increasing burden of on-board cabling requires wireless solutions. Moreover, concerns such as safety or system lifetime often preclude the use of electrochemical energy storage. Ambient energy capture, storage and management are therefore key topics. In this paper we illustrate these concepts by describing an actual implementation in the engine harsh environment of an Airbus A380. A thermogenerator was used to harvest ambient energy and the electronics associated with it allows the local system being energy autonomous. All items were devised and tested in order to meet the criteria of DO-160G aeronautical standard. The set of equipment was mounted on aircraft, and submitted to tens of test flights during roughly a year, in very various flight conditions.