About Airspace Change

The CAA assign a ‘level’ to permanent airspace 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 are assigned one of the levels below.

Level 1

A change to the notified airspace design that has the potential for a high impact on aviation and/or non-aviation stakeholders. We would expect changes that have the potential to alter flight behaviours below 7,000 feet (above mean sea level) over land to fall within this level.

Level 2

A change to the notified airspace design that has the potential for a medium impact on aviation and/or non-aviation stakeholders. We would expect changes that have the potential to:

• alter flight behaviours above 7,000 feet (above mean sea level) or
• alter flight behaviours below 7,000 feet (above mean sea level) over sea and
• not alter flight behaviours below 7,000 feet (above mean sea level) over land

to fall within this level.

Level 3

A change to the notified airspace design that has the potential for a low impact on both aviation and non-aviation stakeholders.

Although the requirements vary depending on the type or level of the airspace change proposal, the airspace change process requirements for Level 1 and 2 permanent airspace change proposals are described below.

You can find the full process for Level 1 and 2 changes in CAP 1616f: Guidance on Airspace Change Process for Permanent Airspace Change Proposals.

Level 3 permanent airspace change proposals have a set of minimum requirements which are detailed in CAP 1616h – Guidance on Airspace Change Process for Level 3 and Pre-Scaled Airspace Change Proposals.

Stage 1 DEFINE

Stage 1 is where the change sponsor produces a statement of need. The statement of need defines their requirement for a proposed change to airspace design, setting out the objectives, issues and opportunities associated with the airspace change.

An assessment meeting will then determine whether the airspace change process is the appropriate mechanism for the change. Following the assessment meeting, the change sponsor will agree a timeline for the proposal with the CAA.

The change sponsor must then describe the current-day scenario and develop design principles, which provide a framework against which design options can be developed and evaluated. These are shared with key stakeholders, following which the change sponsor must demonstrate what they have heard and how their stakeholders’ feedback has, or has not, informed the content of the current-day scenario and development of the design principles.

Stage 2 - DEVELOP and ASSESS

Stage 2 is where the change sponsor develops design options for the airspace change proposal and the baseline scenarios, which allow a comparison to be made between the impacts of the design options and the impacts without an airspace change.  

The change sponsor engages with relevant stakeholders on the baseline scenarios and design options, prior to conducting a design principle evaluation. This evaluates the design options against the design principles that were developed in Stage 1 and may result in some options being discounted.

The change sponsor then carries out an initial options appraisal, where the impacts of the remaining design options are assessed against the baseline scenarios, and further options may be discounted.

Options appraisal is an iterative process that is developed as the change sponsor refines its proposals, with a full options appraisal conducted in Stage 3 and a final options appraisal in Stage 4. The options appraisal provides clear, comparable evidence  on a range of factors, enabling a consistent comparison and assessment of different airspace design options for a given proposal.

Stage 3 - CONSULT/ENGAGE

During the ‘consult/engage’ stage, the change sponsor develops the initial options appraisal into the full options appraisal, providing a more quantitative assessment of the remaining design options.  

The change sponsor then prepares for consultation. This is the key stage of the airspace change process when change sponsors seek feedback to help them understand stakeholders’ views about the impacts of their airspace change proposal. Whether this requires a full public consultation or targeted engagement with relevant stakeholders will depend on the scale and impacts of the airspace change proposal.

Once the stage 3 gateway, which occurs in the middle of stage 3, has been passed the change sponsor launches its consultation.

Following the consultation, the change sponsor must collate and review consultation responses. Stage 3 is completed with the publication of the change sponsor’s consultation response document on the airspace change portal.

Stage 4 - UPDATE and SUBMIT

In stage 4, the change sponsor makes any final adjustments to their airspace design ahead of submitting the final airspace change proposal to the CAA.

Change sponsors select a final design option and consider any updates based on feedback from the consultation or engagement.

The change sponsor will complete the final options appraisal and assess whether additional consultation or engagement is required.

Stage 4 is completed with the submission of the final airspace change proposal to the CAA. This includes any supplementary documents, annexes or appendices, along with publication (redacted where appropriate) on the airspace change portal.

Stage 5 - DECIDE

Stage 5 is where the CAA reviews and assesses the final airspace change proposal. The CAA may need to request supplementary information or technical corrections and clarifications from change sponsors.  

For level 1 proposals, the CAA may convene a public evidence session and/or publish a draft decision, when it is proportionate to do so.

The CAA will then decide whether to approve the final airspace change proposal. The CAA’s decision may be subject to modifications to, and conditions on, the final airspace change proposal as the CAA considers necessary. These modifications and/or conditions will need to be fulfilled by the change sponsor either before, or after, implementation.

Alternatively, the Secretary of State may ‘call-in’ the proposal and make the decision, and the CAA will instead give the Secretary of State a ‘minded to’ decision. You can find more information about how the Secretary of State call-in works on this page. 

Stage 6 - IMPLEMENT

Stage 6 is where the approved airspace change is implemented. The change sponsor must fulfil any conditions or modifications set out in the regulatory decision, finalise and submit aeronautical data to the CAA for validation and update all relevant documentation where needed.

During stage 6, the change sponsor must monitor the impacts of the change. The change sponsor must continue to engage with stakeholders and consider feedback received regarding the impacts of the airspace change.

Stage 7 Post Implementation Review

Stage 7 is where the post implementation review analyses the impacts of the implemented airspace change to allow the CAA to determine if it has produced the intended outcomes. The post implementation review is not a review of the decision that was made on the final airspace change proposal, and it is not a re-run of the decision-making process.

A post implementation review must be completed for all Level 1 airspace change proposals. It will only be completed for Level 2 and Level 3 airspace change proposal when the CAA determines that it is proportionate to do so. 

You can read more about the post implementation review process on our post implementation review pages.

Should a change sponsor believe that they have identified a change in airspace design that will not alter air flight behaviours but is unsure whether they are able to submit an aeronautical information publication change request directly to the UK Aeronautical Information Service, they should approach the CAA so that an assessment can be made. Examples of when a change sponsor should approach the CAA include:

• seeking confirmation from the CAA that a change to airspace design will not alter flight behaviours:
  • considering the relocation of a navigational aid which is refenced by a flight procedure, where the change sponsor has demonstrated the new location of the navigation aid will not impact the airspace design.
• checking with the CAA that a change to airspace design will not have unintended impacts that have the potential to alter flight behaviours:
  • considering the movement of an aerodrome reference point. In this instance the aerodrome reference point may be directly referenced by other elements of airspace design that may need to be considered before the change can be approved
  • considering a request to amend an activity descriptor within a danger area. In this instance this can require consideration of wider policy requirements that have the potential to impact the design of surrounding airspace.

In any such case, the change sponsor should submit a DAP1916 – statement of need to provide a brief description of the proposed change. The CAA will review the statement of need and will use this information to assess the proposal and advise the change sponsor accordingly.

If the CAA accepts that the change to airspace design will not alter flight behaviours we will provide a ‘change request authority’ to the change sponsor confirming that they can submit a change request authority directly to the UK Aeronautical Information Service. While there will be no requirement for the proposal to progress through the airspace change process, the statement of need and the change request authority will be published on the airspace change portal.

If the CAA determines that the change to airspace design has the potential to alter flight behaviours, the change sponsor will be required to follow the airspace change process outlined above.

Specific events or operating conditions may sometimes require a temporary change to the notified airspace design.  A temporary change will usually apply for a period no longer than 90 consecutive days, after which the airspace will revert back to its original form. Should a change be required for longer than 90 days, or should we receive a request to repeat a temporary change that has previously been in effect for 90 days, a permanent airspace change proposal will normally be needed. 

An airspace trial is defined as changes to airspace design, or air traffic control operational procedures (which if subsequently made permanent would constitute a relevant planned and permanent redistribution of air traffic), of a temporary nature for the purposes of:   

• investigating the feasibility of, or validating proposals for, innovative airspace design, technology or air traffic control operational procedures 
• assessing its performance and effect 
• supporting the development and integration of new airspace user groups into UK airspace.  

An airspace trial may result in the establishment of a temporary airspace structure (such as temporary special use airspace). However, the distinction from a temporary airspace change should be noted. An airspace trial is where innovative airspace design, technologies or procedures are being trialled. A temporary airspace change is used to meet a specific event or operating conditions for a short period. 

The duration of an airspace trial can vary and is for a fixed period as the CAA considers appropriate, which is normally not more than six months. 

The airspace change process for temporary changes to the notified airspace design and airspace trials is summarised below. There are no gateway assessments for temporary or trial airspace change proposals. 

Stage 1 - Define 

The first stage of the temporary and trial airspace change process, the ‘define’ stage, is where the change sponsor submits a statement of need setting out the objectives of their airspace change proposal and the airspace issues or opportunities that it seeks to address. An assessment meeting to discuss the statement of need takes place and, subject to the CAA accepting that the airspace change process is the appropriate mechanism to achieve the objectives of the temporary or trial airspace change proposal and address the airspace issues or opportunities, the change sponsor will go on to the remaining stages of the airspace change process. 

Stage 2 – Develop and Assess 

For temporary and trial airspace change proposals, the requirements for Stage 2 will depend on the nature of the airspace change proposal. The size, complexity and duration of the proposal will be taken into consideration when scaling the requirements of this stage and will be discussed at the assessment meeting.  

The change sponsor must develop at least one design option and conduct impact assessments for the airspace change proposal. There is no requirement for the change sponsor to conduct the full options development process, design principle evaluation or initial options appraisal. 

Stage 3 – Engage 

Stage 3 is where the change sponsor gathers information from stakeholders to understand whether the temporary or trial airspace change proposal will be safe and operationally viable. For temporary and trial airspace change proposals, a scaled form of consultation – engagement – is appropriate at Stage 3. 

After developing engagement material, the change sponsor launches their engagement activities. The change sponsor’s explanation of the issues raised during engagement, and its response to the identified issues, must be included as part of the final airspace change proposal submission in Stage 4. The CAA will assess the effectiveness of the change sponsor’s engagement at Stage 5. 

Stage 4 - Update and Submit 

Stage 4 is where the change sponsor considers the need to update the final design option and its impacts in light of information received during the engagement period. The change sponsor also assesses the need for additional engagement, and makes any final adjustments to the airspace design. Stage 4 is completed with the submission of the full and unredacted version of the final airspace change proposal to the CAA, including any supplementary documents, annexes or appendices, along with publication (redacted where appropriate) on the airspace change portal. 

Stage 5 - Decision 

Stage 5 is where the CAA reviews and assesses the final airspace change proposal. The CAA may need to request supplementary information or technical corrections and clarifications from change sponsors. 

The CAA then decides on whether or not to approve the final airspace change proposal. The CAA’s decision may be subject to modifications to, and conditions on, the final airspace change proposal as the CAA considers necessary. These modifications and/or conditions will need to be fulfilled by the change sponsor either before, or after, implementation. 

Stage 6 - Implement 

Having completed the ‘decide’ stage, the change sponsor moves on to the ‘implement’ stage. This is where the change sponsor engages with the CAA and UK Aeronautical Information Service to implement the temporary or trial airspace change using the most appropriate method. Once implemented, the change sponsor will monitor the impacts of the airspace change by collating and reviewing feedback from stakeholders.      

Stage 7 – Post Trial Report (airspace trials only) 

There is no post implementation review required for temporary or trial airspace changes. However, for airspace trials, the change sponsor is required to produce a post-trial report and publish it on the airspace change portal.

As a minimum the change sponsor must report against the aims and objectives of the trial as detailed in the final airspace change proposal, including whether they were successfully achieved and report on any engagement conducted during the trial and the content of any feedback or complaints. The change sponsor must publish the post-trial report on the airspace change portal and provide a copy to the CAA for review.

A PPR is when there is no change in airspace design, but there is a planned and permanent redistribution of air traffic through changes in air traffic control operational procedure. “Planned and permanent” means other than a day to-day or at the time decision taken by an air traffic controller or other decision-maker.

A PPR follows a similar seven-stage process to the airspace change process, including consultation at Stage 3, but there are some differences. The full process can be found in CAP1617: Planned and Permanent Redistribution of Air Traffic (PPR).