The tragic events of 11 September 2001 have drastically changed the way in-flight security incidents are managed. National Security Agencies are more reactive to any indication that could lead to security concerns, such as the prolonged loss of radio communication with ATC, also known as COMLOSS, but there is no consistency worldwide in the way these occurrences are addressed. In some countries, COMLOSS events have resulted in unnecessary interceptions of aircraft and/or administrative sanctions against the pilots involved, which will not solve the problem. In today’s complex radio communications environment, COMLOSS can be triggered by a number of factors, and these should be fully taken into account prior to any State reaction.
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