The use of wireless networks to effectively support hard real-time communications in the extremely harsh conditions that avionics and aerospace systems and applications face aboard (unmanned) autonomous vehicles is still an open issue. This paper starts by defining and exploiting the properties of the Wireless network Segment (WnS), a broadcast space where all communicating devices are at one-hop distance of each other. Then we discuss how to exploit and secure the properties defined for the WnS and how those can be used to support low level (frame) error monitoring and failure detection functions and, more importantly, how such mechanisms can be used as building blocks to architect, above the Wns, Resilient Hard Real-Time protocols and services, such as reliable communication, node failure detection and membership, clock synchronisation and a global notion of time. Such kind of protocols and services are extremely helpful to build wireless-based distributed applications, and the mechanisms and properties one introduce in the WnS definition constitute a first step towards the provision of similar guarantees in multi-hop interconnected WnS networks.