International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / More and more aircraft system designs are incorporating a local-area-network (LAN) using either Fibre Channel (FC) or Ethernet. To date there hasn’t been a means for creating a FC node connection between an airborne network and a ground based FC network or for creating a reliable high-speed Ethernet connection between air and ground. Ethernet connections have had some success by using the IEEE 802.11 wireless LAN for these types of connections; however, these connections suffer from many inherent problems using this standard. Problems include the lack of telemetry spectrum control, security validation, high-speed data transfer efficiency, and channel acquisition time. This paper will describe a methodology that utilizes the IRIG-106 PCM standard for communicating between aircraft and ground-based networks. PCM can solve the aforementioned problems and it enables the user to take advantage of the many ARTM advances in PCM telemetry technology [1]. One such advance in technology has been the use of SOQPSK (Tier 1) or Multi-h CPM (Tier 2) to enable the user to effectively double or more their bandwidth efficiency compared to PCM/FM (or CPFSK) (Tier 0).