Third
runway and NATS proposals By Michael Jepson
Following my earlier note ‘A Ray of Hope from NATS?’ (September 2008 Newsletter) there have now been further developments, the first being the decision of the Government, approved in Parliament, to proceed with the proposed third runway at Heathrow. This will further impact on the Chilterns AONB.
At present, because of the Bovingdon Stack for flight arrivals to Heathrow, all westerly departures from Heathrow which proceed to the north (mainly north Atlantic flights) cross over the Chilterns at heights which have to keep below the Stack. On top of that (or in fact below!) the departures from Luton have to be lower still, as these have to cross under the Heathrow departures. The addition of a third runway, which would be geographically nearer to us than the existing runways, will entail a further increase in the number of Heathrow takeoffs passing over the Chilterns.
Stacked against us?
For this reason, many of the objectors to the NATS proposals had called upon NATS to include a repositioning of the Bovingdon Stack in their review, as, if this was moved, it should be possible to allow all these other flights to pass over the Chilterns at higher levels. However, to date, they have resisted this on the grounds that it is a major change which is not feasible to include in what is already a significant review of airspace in the area.
However, in an earlier consultation report to BAA on the possibility of a third runway, NATS’s then view was that the safety, capacity and environmental objectives that will drive a significant airspace re-design in the time period for the third runway will almost certainly require the re-positioning of the existing Heathrow holding patterns further out from the centre and at higher altitude. Logically, therefore, the recent decision to approve the third runway should now call for the inclusion by NATS of the Bovingdon stack/holding pattern in its overall airspace review.
This aspect has therefore been taken up with NATS and CAA by the Chilterns Conservation Board reminding them of this conclusion in their earlier report and calling on them to now include a review of the Stack within their overall proposals.
Cautious response
They have now received a reply from CAA (see below) and NATS has also separately sent out a general letter to announce that they will be conducting a further consultation later this year. This has no doubt resulted, in no small part, from the very high level of responses and comments they received to their earlier report… so the pressure has paid off. In NATS’s earlier feedback to the responses to their consultation paper, they said that they were now considering “further design options…. with priority given to the AONB rather than the populations”. However they also added that feedback favours “dispersal over concentration”, so that keeping easterly and westerly departure routes separated for longer will mean that different areas are over-flown depending on the direction of operations. This implied that NATS may well be considering two separate flight paths for Luton departures, one possibly following the existing route for takeoffs to the west (where there is no conflict with flights landing as these come in from the other direction) and another for flights taking off to the east and turning back to proceed to the SW, where there is then potential conflict with planes landing from the west.
Back to the drawing board
As they are now considering new options, it could be that they will now be able to consider moving all these northwards which will, in itself, not only allow flights to be higher but they would pass over lower ground levels than the 700/800 feet levels of the Chilterns AONB. However they do say that the east to SW flights have to be separated from landings from the west, with the implication that unless the landing flight paths themselves can be moved further north or unless their navigation systems allow for a narrower separation then NATS may argue that these flight paths need to be further south and therefore still need to pass over the Chilterns AONB.
In this respect, NATS has indicated that it will also seek to apply P-RNAV, a more precise navigation system. This might turn out to be good or bad news. The system may concentrate flights over a more specific area, which could be bad news for those under those flight paths but, if it is more accurate, then they may well be able to narrow the ‘conflict’ lines and even move all the paths further north, which may perhaps enable them to avoid the AONB. What is also of concern, however, is that they still assert that the impact of any Heathrow runway changes will need to be a separate exercise so that, at this stage, they do not intend to include a review of the Bovingdon stack in their current deliberations even though this is the reason for all these flights being lower.
This leads on to the CAA reply which says the same about the stack although it indicates that they expect that NATS will be mindful of the requirement to avoid having to ‘unpick’ changes that may be necessary in advance of the third runway being constructed. This implies that NATS would take into account possible later changes in the stack but this may also merely mean that the routes would be unchanged but that they will allow the flying heights to be increased later if the stack is moved.
It is unfortunate therefore that all this has not resulted in NATS accepting the need to include the stack in its further review, so that, at this stage, except perhaps in relation to the limited reassurance from CAA the Heathrow decision has not as yet triggered any material change.
More action needed
Some of the above is of course merely a speculative attempt to read between the lines and is only conjecture at this stage. Whilst we will have a better idea when the revised consultation paper comes out, the implication of their current remarks is that to accommodate the feedback responses, their choices are now more limited and so they may well be more difficult to challenge next time.
Perhaps therefore more letters to NATS, MPs etc. are needed now as the sooner we can all get the message home the better, before they finalise their thinking.