Section 87.261 - Scope of service(a) Aeronautical enroute stations provide operational control communications to aircraft along domestic or international air routes. Operational control communications include the safe, efficient and economical operation of aircraft, such as fuel, weather, position reports, aircraft performance, and essential services and supplies. Public correspondence is prohibited.(b) Service must be provided to any aircraft station licensee who makes cooperative arrangements for the operation, maintenance and liability of the stations which are to furnish enroute service. In emergency or distress situations service must be provided without prior arrangements.(c) Except in Alaska, only one aeronautical enroute station licensee will be authorized at any one location. In Alaska, only one aeronautical enroute station licensee in the domestic service and one aeronautical enroute station licensee in the international service will be authorized at any one location. (Because enroute stations may provide service over a large area containing a number of air routes or only provide communications in the local area of an airport, location here means the area which can be adequately served by the particular station.)(d) In Alaska, only stations which serve scheduled air carriers will be licensed to operate aeronautical enroute stations. Applicants must show that the station will provide communications only along routes served by scheduled air carriers.(e) Mobile units may be operated under an aeronautical enroute station authorization so long as the units are limited to use at an airport and are only used to communicate with aircraft on the ground or the associated aeronautical enroute station. Mobile units are further limited to operation on the VHF frequencies listed in 87.263(a)(1).(f) Mobile units licensed under paragraph (e) of this section shall not be operated on air traffic control frequencies, nor cause harmful interference to, communications on air traffic control frequencies.53 FR 28940, Aug. 1, 1988, as amended at 64 FR 27476, May 20, 1999