Thu May 23, 2019 3:24 pm
#1695541
Quite simply, this would be disastrous for us here in Scotland with the weather that we have...
Below is what the FI at our airfield has submitted to the CAA, so I can't take any credit for it, but he has urged us all to read it and submit our own response. This proposal could really ruin GA flying for us
Question 1: Do you agree with the CAA’s assessment of typical weather conditions in the UK?
No. The data used consist of Met Office records of “cloud ceiling” at or below 3000ft amsl. But ‘cloud ceiling’ is defined in SERA as cloud covering more than half of the sky – equivalent to the METAR codes OVC and BKN. In practice, if there is SCT cloud (3 or 4 oktas) at or below 3000ft, and even in some circumstances with FEW at those levels, aircraft flying VFR transits will be flying at levels that keep them below all cloud. So the data used in the consultation document will be significantly under-estimating the frequency with which VFR transits will be affected by the proposed new rule. It should also be noted that SERA.5001 doesn’t require 1000ft vertical separation from the cloud ceiling or cloud base; it requires 1000ft separation from any cloud.
We also note that the prevalence of cloudbases lower than 3000ft is significantly greater in Central Scotland and Northern Ireland than other parts of the UK. The proposed changes will therefore have greater impact in those areas. Forcing more than 81% of current VFR transits to request a Special VFR clearance is in our view unacceptable for the reasons outlined below.
Question 2: Do you support the CAA’s preferred option and the associated assumptions?
We do not support the CAA’s preferred option, for the following reasons:
1. The high frequency of cloud below 3000ft in Scotland means that a very high proportion of current VFR transits will be forced to either (a) fly lower than they normally would, in order to maintain 1000ft vertical separation from cloud, or (b) request a Special VFR clearance. Pilots choosing to do the former will have less safety margin in the event of an engine failure and will be at higher risk of contravening the SERA rules on minimum heights. There is no acknowledgement of this safety disbenefit in the consultation document.
2. Pilots choosing to request a Special VFR clearance will then be subject to ATC separation from all IFR flights. In busy CTRs such as Edinburgh, Glasgow and Aberdeen this will create significant delays as controllers hold SVFR traffic at least 3nm away from approach/climbout paths, awaiting a gap to allow the SVFR traffic to cross. At Edinburgh in particular this is highly likely to involve lengthy periods when SVFR aircraft are orbiting awaiting onward clearance, with the potential for subsequent SVFR traffic having to be held further back. Typical SVFR traffic will take at least four minutes to make the 6nm crossing, during which time no IFR movements will be possible. The only possible outcome of that is that ATC will refuse all SVFR transit requests unless they can guarantee no impact on IFR arrivals or departures.
3. The reality, or VFR pilot expectation, of SVFR zone transit refusals will lead to many more VFR pilots choosing to route around the CTR. At Edinburgh this has serious safety implications. A route to the east of the CTR takes aircraft on a sea crossing of at least 8nm, during which they must remain below the Edinburgh CTA at 2500ft. This is insufficient altitude to glide to land in the event of an engine failure and increases the risk of vertical infringements of the Edinburgh CTA in a critical area under their main approach path. VFR traffic avoiding the CTR to the west would be forced to fly through a narrow corridor where again the base of controlled airspace is 2500ft and there are obstacles up to 1938ft and restricted areas further constraining traffic. Once again this is likely to increase the risk of vertical infringements of controlled airspace under Edinburgh’s approach paths and will also increase the risk of conflicts with other VFR traffic since aircraft avoiding the Glasgow CTR will also be in this area.
4. The consultation document asserts that increased vertical distance from cloud increases the efficacy of see and avoid in Class D airspace. This is highly debatable. Because aircraft currently flying VFR transits are in the vast majority of cases flying below all cloud, it is extremely rare for visual acquisition of conflicting traffic to be compromised by cloud between the two aircraft. We can see no basis for asserting that see and avoid will be improved under the proposed rule.
Question 3: Do you agree with the CAA analysis of the projected workload change for ATC units and the effectiveness of the proposed mitigation?
No. It is the requirement for separation of SVFR from IFR that is the principal driver of the increased controller workload, not separation of SVFR from SVFR. The proposed mitigation – removing the requirement to separate SVFR from SVFR – is insignificant by comparison because (in our experience) there is much more IFR traffic in CTRs than VFR. The proposed change will result in VFR traffic occupying the CTR for much longer than currently, and requiring large gaps between IFR arrivals/departures to transit over the airport, leading to multiple additional RT exchanges and a more complex relationship between Approach/Radar and Tower controllers for the handover of SVFR traffic. All of this will lead to increases in controller workload which we predict will inevitably result in many, perhaps all, SVFR transit requests being denied.
Question 4: Do you agree with the CAA analysis of the potential impact on the provision of non-IFR flight? Are there any additional factors you feel should be considered?
We submit that the consultation document does not adequately address the practical impacts of the proposed change in terms of what VFR pilots will choose to do and the safety implications of those choices. Nor does it consider the context of cost-cutting and personnel shortages in ATC. VFR transits through the Glasgow CTR have already been restricted for long periods due to ATC staff shortage and Edinburgh ATC already have in place a telephone advance booking system for VFR transits, which, if not used, can lead to delays in obtaining a clearance or even a refusal.
It is clear that the sole reason for this proposed rule change is so that the UK can demonstrate full compliance with SERA, which the document notes is “directly applicable EU law”. But the UK is leaving the EU. Surely, then, it is better to wait until we find out whether and under what terms the UK is leaving, before applying rule changes that may be irrelevant in a few months’ time?
Question 5: Do you agree with the CAA’s assessment of safety impact?
No. There is no mention of the impact on pilots who, knowing that if they ask for an SVFR clearance they will get either a refusal or lengthy delays, request a VFR transit and then fly much lower than they normally would in order to meet the 1000ft vertical separation from cloud requirement. This is particularly acute in the Glasgow and Edinburgh CTRs where the combination of high ground, obstacles and congested areas means there is only a very narrow altitude band between the normal maximum VFR clearance altitude and the minimum height for clearing obstacles and congested areas.
- Adam
Last edited by Hutchy96 on Thu May 23, 2019 6:42 pm, edited 1 time in total.