Airspace change proposals vary greatly in size, complexity and length. Some proposed changes may be permanent, and some may be temporary or trialling something new. We also assign a ‘level’ to permanent change proposals according to their potential impact. This ensures that the more significant proposals receive the right amount of regulatory scrutiny, while keeping the airspace change process proportionate for less significant proposals.
Permanent changes to notified airspace design
Permanent changes to notified airspace design are assigned one of the levels below.
Level 0 proposals are changes that do not alter air traffic patterns because they only involve changes to the wording of existing airspace design.
Given the nature of Level 0 changes, they are only required to complete Step 1a of the process.
Level 1 are changes that could alter change air traffic patterns below 7,000 ft over an inhabited area. These can include departure and arrival routes at airports.
The CAA will only describe a change as Level 2 if it is expected that it will not alter air traffic patterns below 7,000 ft over an inhabited area. They are described as medium to low impact changes. They are sub-divided into Levels 2A, 2B and 2C according to impact:
- Level 2A changes usually affect aircraft routes between 7,000 ft and 20,000 ft
- Level 2B changes usually affect aircraft routes above 20,000 ft, over the sea, or are outside controlled airspace above 7,000 ft
- Level 2C changes usually reflect current airspace use or remove an existing airspace structure
Level M changes are sponsored by the Ministry of Defence (MoD). Military changes still go through the airspace change process, but they follow different environmental rules to other proposals. They are split into M1 (which could change civil air traffic under 7,000 ft) and M2 (which will not).
These proposals complete all steps of the process in the same way as Level 1 or Level 2 changes respectively.
Temporary changes to airspace design
Temporary changes to airspace design usually last less than 90 days, except in extraordinary circumstances. These changes complete Steps 1, 3, 4 and 5 of the airspace change process before they are introduced. During operation of the temporary change, the CAA receives information about engagement, monitoring and feedback from the change sponsor. Complaints from the public are part of this feedback process (see the next page).
An airspace trial is a trial of airspace design or air traffic control operational procedures which may or may not lead to a proposal for a permanent change. Trials usually last no longer than six months, although the CAA may extend this period if it has not been possible to collect the data that the sponsor expected to, for example if a full range of weather conditions has not been experienced.
These changes complete Steps 1, 3, 4 and 5 of the airspace change progress prior to implementation. During operation of the trial, the CAA receives information about engagement, monitoring and feedback from the change sponsor. Complaints from the public are part of this feedback process (see the next page).