UK Flight Information Services (UKFIS) are provided to aircraft operating outside of controlled airspace (Classes E and G), both VFR and IFR.
Regardless of the service being provided, pilots are ultimately responsible for collision avoidance and terrain clearance.
UKFIS provision is constrained by the nature of the airspace environment in which the flight takes place. It is not mandatory for a pilot to be in receipt of a service in Class E or G airspace and this generates an unknown traffic environment in which Controller or Flight Information Service Officer workload cannot be predicted and where pilots may make sudden manoeuvres, even when in receipt of a service.
Controllers shall make all reasonable endeavours to provide the service that a pilot requests. However, due to resources or controller workload, tactical priorities may influence service availability or its continued provision.
A pilot shall determine the appropriate ATS for the various phases and conditions of flight and request that ATS from the controller/FISO. If a pilot fails to request an ATS, the controller/FISO should normally ask the pilot to specify the ATS required, apart from the following circumstances: