The CAA’s post implementation review of P-RNAV

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In line with CAA requirements, aircraft departing from Gatwick now fly using a method known as ‘Precision Area Navigation’ (P-RNAV). The system means departing aircraft follow more precise flight paths and has been introduced so that the CAA can eventually switch off ground-based navigation systems across the UK. 

Before any of this could happen, Gatwick had to design and introduce new flight paths that sit within the airport’s nine noise preferential routes (NPRs) or corridors that departing aircraft fly within. Aircraft started flying these modified flight paths in late 2013 and early 2014 and these routes have just been reviewed (post implementation review) by the CAA to see if they are compliant with regulations. 

Below is the 14th update in our series of blogs updating on progress following the CAA’s review.  

Update by Charles Kirwan-Taylor, Corporate Affairs & Sustainability Director

12 September 2016

Charles Kirwan-TaylorThe amendment to Route 4 has been in place for over three months now and we continue to engage with our airline partners to explore further opportunities to improve track keeping.

During the month of August we operated in a westerly direction for 75% of the time. During that period 3,970 aircraft flew the amended Route 4 Standard Instrument Departure routes and our track keeping achievement rate for the month was 94.35% Once again we are in the process of providing our monthly delivery of Route 4 related information to the Civil Aviation Authority for their continued consideration and assessment of this amendment.

We are aware that since the re-introduction of air traffic to the Noise Preferential Route, a number of community campaign groups have questioned the background to these changes so I reiterate that this amendment has been made to better ensure compliance with the Noise Preferential Route, in accordance with the instruction from the CAA. The maps below are density maps for August 2015 and August 2016, showing how the amendment has affected the position of aircraft using Route 4 – I would like to emphasise again that the Noise Preferential Route outlined in the chart has been in its present location for many years and has not been altered.


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Previous blogs

4 August 2016 
8 July 2016 
22 June 2016  
13 June 2016 
1 June 2016 
26 May 2016 
24 March 2016 
24 February 2016 
18 February 2016 
8 February 2016 
31 January 2016 
21 January 2016 
23 December 2016