Division 4 The ATFM function shall be governed by the following principles:

ATFM measures shall:

1. (i)

   support safe operations and prevent excessive air traffic demand compared with declared ATC capacity of sectors and aerodromes including runways;

2. (ii)

   use F1UK ATMS capacity to the maximum extent possible in order to optimise the efficiency of the UK ATMS and minimise adverse effects on operators;

3. (iii)

   optimise the UK ATMS capacity made available through the development and application of capacity enhancing measures by ATS units;

4. (iv)

   support the management of critical events.

the allocation of ATFM departure slots shall give priority to flights according to the order of their planned entry into the location at which the ATFM measure will apply, unless specific circumstances such as those stemming from security and defence needs, require application of a different priority rule which is agreed and is of benefit to the UK ATMS;

trajectory times in the planning and execution phases shall be consistent with any applied ATFM measures and shall be communicated by the F2CAA to aircraft operators, ATS units and local ATFM units;

flights departing from the geographical area where ATFM measures are applied and adjacent Flight Information Regions as described in the appropriate ICAO documentation shall be subject to ATFM slot allocation. Flights departing from other areas shall be exempted from ATFM slot allocation but shall however be subject to route, traffic orientations schemes and trajectory time constraints.