The CAA is carrying out an initial consultation with organisations such as the LAA on NATS’ proposals to remove all but 19 of the 46 en-route VORs.   The input from this will be used by a CAA led focus group to look at the impact and if the proposal goes ahead there will be a full public consultation run by NATS.  This double arrangement is an excellent way of ensuring that the impact on all users is considered.  Please tell us what you think by Tuesday 10 November and if you have expertise in this area and would like to represent the LAA on the focus group, please tell us that as well.  Email us here.


Traditionally, airways are defined by NDBs and VORs but the days of aircraft flying from beacon to beacon are going or gone.  Increasingly aircraft which fly in controlled airspace use Area Navigation (RNAV) to follow routes which may be more direct or which enable more aircraft to fit into the airspace.  To fly from point to point these aircraft use flight management systems with inertial navigation platforms which are updated either by GPS or by automatically tuning DMEs or VORs.  In the latter case the aircraft only need sufficient beacons within range to maintain navigation accuracy; they do not need beacons to be part of the route.


In the UK today, Basic RNAV (B-RNAV) is required for flight on ATS routes above FL95 and it likely that it will be required at all levels by next year.  European policy sees the removal of all en-route NDBs by 2015 together with a reduction in the number of VORs to that needed to support B-RNAV and this is what NATS now proposes.  The present 10 en-route NDBs would be removed in 2012 and the 46 en-route VORs would be reduced to 19 starting in 2011.  The DMEs that are co-located and frequency paired with VORs would remain in service, probably because unlike VORs they are cheap and simple.


The NATS proposal only considers the effect of this change on aircraft within the ATS route structure but of course other aircraft use these beacons for general navigation and to ensure they do not infringe CAS; indeed, we train our private pilots to use radio navigation aids as part of the PPL syllabus.  You may think that we should now be training pilots to use GPS so perhaps there is a need to look at the wider implications of the proposed change rather than just focussing on airline needs.  Another issue relates to safety of flights using RNAV.  It is best practise for pilots to tune and monitor a suitable navaid during descent to guard against “map shift” in which an RNAV system can introduce a false position.  This is commonly done with a VOR/DME close to destination and no other single navaid can offer the same degree of instant position check.


Interestingly, in parallel with this but not mentioned in this consultation, the CAA is also consulting on a new scheme of charges which will have an effect on some parts of GA.  Whilst the costs of RNAV approval for airlines falls within the charges for its AOC, the CAA now proposes a 3-yearly charge to individual GA aircraft of £674 for permission to enter P-RNAV en-route airspace and £3,796 for terminal airspace.  That is in addition to the cost of aircraft equipment installation and EASA charges for approvals, certification and so on.


Please tell us what you think about the proposal and we will send a consolidated response to Director Airspace Policy.