Originally Posted by A I
All ACC's have to monitor 121.5MHz as it is an ICAO requirement. For both London and Scottish FIR's this is done on NATS behalf by London and Scottish Mil. Both civil centres have the capability to select 121.5 MHz when required.
The position fixing bit is a requirement of the CAA in the licence issued to NERL. It has to be on VHF (not necessarily 121.5MHz) and again is delegated to the Military operation. Although I don't know for certain it seems likely that both of these services are covered in the NATS/MoD contract.
A I
Found the exact wording at last. Under the NATS Operating Licence from the CAA, a Memorandum of Agreement between MoD and CAA and under contractual arrangements between NATS and MoD, MoD Controllers provide an Alerting and Fixing Service to aircraft which declare an emergency using NATS and MoD owned ground based radio and radar assets.
Under the Air Traffic Services Licence for NATS (En Route) plc (1-Nov-03), Condition 3 controls modification of Specified Services, defined in Schedule 4 to include “Emergency Fixing Facility”, which is “The making available of radio-communications facilities to enable the identification of the position within the Licensed Areas of aircraft communicating on very high frequency.”
BD