Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model ERJ 170 Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain EMBRAER Model ERJ 170 airplanes. This AD requires replacing the very high frequency (VHF) antenna located in position 1 of the fuselage with a new, improved VHF antenna. This AD results from a report of the loss of all voice communications due to a lightning strike damaging all the VHF antennas. We are issuing this AD to prevent the loss of voice communication, which, when combined with the complexity of the national airspace system, could result in reduced flightcrew situational awareness, increased flightcrew workload, and increased risk of human error, and consequent reduced ability to maintain safe flight and landing of the airplane.