We aim to publish the full contents of all documents received by us during the change process. Occasionally it will be necessary for us to consider, under our Environmental Information Regulation obligations, whether some information can be disclosed, balancing the rights of the owners of the information against the public interest in transparency,
especially information which is commercially confidential or protected by intellectual property rights.
Last updated: 19 June 2018
In November 2014 we commenced the Post Implementation Review (PIR) of the November 2013 changes to the standard instrument departure routes (SIDs) at Gatwick which enabled the use of modern satellite technology for air navigation for the first time.
The purpose of the PIR is for the CAA, as the independent regulator, to assess whether the change has delivered the anticipated impacts and benefits set out in the original airspace change proposal and decision, and if not to ascertain why and determine the most appropriate course of action.
PIR report was published on 11 November 2015. Following the conclusion of the PIR, the CAA advised the sponsor of the outcome of the CAA review (see below). A number of requirements for modifications to Routes 2, 4 and 5 were provided to the sponsor, together with technical
recommendations regarding how a better replication may be achieved.
The documents referred to will be published as soon as possible after the CAA receives them unless otherwise stated.
8 Nov 2011
23 Apr 2012
30 Nov 2012 (v1.0)
9 Jan 2013 (v1.1)
CAA decision letter to Gatwick Airport Limited
Supplementary operational support
We have requested more information from the organisation that requested the change
Further data sent to us by the organisation that requested the change
Communications with Change Sponsor
We share our report in final draft with the organisation that requested the change, in confidence. This is not an opportunity for them to amend our conclusions but a check for errors.
Report of the CAA's Post Implementation Review of the Implementation of RNAV-1 Standard Instrument Departures at Gatwick Airport
Access the six annexes to this report
Gatwick has not yet submitted the modifications to these routes required by the CAA.
Gatwick has submitted revised designs to the CAA.
The designs have been returned to Gatwick for further procedure design work and re-submission to the CAA.
There is no estimate yet when the revised routes will first be flown. However, at time of writing (10 May 2016) this not anticipated to be sooner than 13 October 2016.
Gatwick will carry out a similar community engagement programme in respect of these modifications once the designs have been validated by the CAA.
Gatwick has submitted to the CAA a revised design to meet our requirements dated 28 September 2015. The CAA has validated that the design meets international design requirements.
They published the revised design on its blog on 24 March 2016 which has since been updated. See Gatwick airport's airspace blog for details.
Gatwick delivered leaflets to 30,000 households, placed advertisements in local papers and held two drop-in sessions for members of the public also in March 2016.
The revised designs will begin to be flown from 26 May 2016 and monitored for 6 months.
Gatwick will be required to collate feedback received on those routes during that time and submit it to the CAA as part of that monitoring exercise.
Comments about the use of Route 4 should be sent to Gatwick during this period at firstname.lastname@example.org.
In addition to the re-design work outlined above, in order to meet our modification requirements dated 28 September 2015, Gatwick is also considering whether it is possible to develop a re-design that is only used in strong wind conditions.
This possibility is being considered by Gatwick in conjunction with the airline operators and Air Traffic Control at Gatwick Airport and NATS Terminal Control at Swanwick.
If an appropriate RNAV SID design and air traffic control operational procedures can be developed, Gatwick will submit a design to the CAA as part of this PIR process.
Re-designed Route 4 SID implemented.
The revised Route 4 design was implemented on 26 May and will be operated and monitored for six months. At the end of that monitoring period the revised design will remain operational whist the CAA considers the data collected during that monitoring phase. The CAA will make and publish its decision whether or not the modified design is acceptable as soon as possible. We hope that this will be within three to four months.
The objective of the re-design is set out in our letter to GAL dated 23 May 2016 which is available on our website (link above, under 23 May entry). In addition to the operational requirements of any SID, the objective of the modification requirement is that aircraft tracks replicate the nominal track of the conventional SID adjusted for magnetic variation.
We will assess where the data shows aircraft are flying and whether they are flying where we anticipated them to be after these modifications. We will use radar track data and the feedback received from local residents to assess this. GAL are tasked with collating both types of data and providing it to us during and at the end of the monitoring phase.
The Route 4 monitoring period of 6 months has come to an end; once GAL provide the CAA with the final data for November, the CAA will commence the PIR review. A decision on whether the modified design is acceptable is expected within three to four months. Until a decision is reached, the modified Route 4 will remain in operation.
We are continuing to assess the large volume of data which appears to indicate that, over time, the slight ballooning in the turn has been reduced.
Route 2 PIR conclusion: The CAA concluded that the track keeping performance of departures had improved and no further action was required; this was notified on the GAL website Airspace Blog on 13 April 2017
The Route 4 data for 6 month utilisation up to 26 November 2016 of the revised Route 4 RNAV1 SID has now been provided to the CAA by GAL, including all the feedback received during that period. The CAA is currently analysing that data.
The 5 year review design for the conventional SID was submitted to the CAA on 15 November 2016 but returned to the design organisation as it did not comply with the regulatory requirements, as previously supplied to GAL. A further revision was supplied to the CAA on 13 December. The CAA is currently assessing that reviewed design.
The revised Route 5 design required by the CAA as an outcome of the PIR (as set out in our letter) has been submitted to the CAA for approval. The design has now been approved for operation and will be flown from 30 March 2017. The CAA will require GAL to monitor the operations for 6 months and provide the data to the CAA.
Route 5 update: PIR data for the modified RNAV SID has been received by the CAA. The CAA will review this data, and will publish the outcome of the PIR together with the data received from Gatwick as soon as our review is complete. No dates have been set for the completion of this work.
7 April 2017 - CAP 1531: CAA conclusions in respect of modification requirements relating to Route 4 RNAV1 SIDs and correction requirements relating to Route 4 Conventional SIDs; CAP 1531 was subsequently revoked on 7 February 2018, retained for reference here along with the following annexes and attachments:
10 May 2018 - letter to GAL outlining the historic copies of the UK AIP showing changes to traffic flying over Route 4 over time:
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