The market forecast for aircraft manufacturers is very promising; the fleet of passenger aircraft will double. This will clearly generate a strong business for aircraft manufactures. But new competitors arise and, hence, rivalry is increasing. To succeed in this market situation, aircraft manufacturers have to build innovative aircraft to set themselves apart from competitors. Most of the research effort is concentrated on developing lighter, more energy-efficient aircraft which reduce operational costs for airline operators. A very promising approach to accomplish this goal is to introduce wireless sensor networks for flight applications. Such wireless sensor networks can be very beneficial: they can help to reduce weight by saving cabling, they can improve workflows and, hence, reduce commissioning and operational costs, and they can enable new applications which were not feasible or even possible before.In this work, flight applications are investigated to identify the challenges which arise when introducing such a wireless sensor network. Technologies and protocols are presented which aim to tackle these challenges. In particular, the most demanding prerequisites are energy efficiency, transmission reliability, scalability, synchronization, and localization. Four of these demands will be addressed by three different protocols. First, a clock synchronization protocol is presented which uses a special hardware devicea wake-up receiverto achieve synchronization in a very energy-efficient, reliable, and scalable way. Second, using this same technology a clustering protocol is presented which can reduce redundant transmissions. In doing so, it becomes possible to lower the mean energy consumption for hundreds of sensor nodes. Last, a custom-tailored medium access protocol is presented which utilizes spatial diversity to increase transmission reliability while keeping a very low power demand.