Wireless networks based on the principle and technology of Wireless Avionics Intra-Communications (WAIC), that is, wireless avionics or wireless onboard intercom are becoming increasingly widespread on modern aircraft. The development and deployment of WAIC on board is a complex task, as its solution is directly related to ensuring safety of flights. It requires preliminary careful scientific analysis. The article defines three stages of the implementation of such systems. At the first stage (it is already going on) there are WAIC on board of the aircraft, carrying out new functions that are new in comparison with traditional networks, for example, the functions of providing passengers with Internet access. At the second stage (this stage has also already begun), the WAIC is being deployed on board of the aircraft, carrying out the already existing functions of traditional on-board networks along with them. For example, the maintenance functions. At the third stage (it is still ahead), WAIC performs functions, completely or partially replacing traditional wired networks. For example, performing the flight control function without wires (FBW). We could see approximately the same process when electric-distance systems were installed on the aircraft instead of traditional mechanical ones. The parameters of XY prospective networks of more than ten aircraft systems have been determined basing on the analysis of onboard equipment systems, in terms of the possibility and expediency of using WAIC in them. The most promising systems for the use of WAIC are the fuel system, fire equipment and gears. Further research calls for the development of wireless sensors with autonomous power supply, information concentrators, appropriate computer software, assessing the impact of wireless information transmission on reliability, fault tolerance and fail-safety of the systems where such information is transmitted and adjacent aircraft systems.