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UK CAA heel dragging on GPS approaches, including LPV (merged)

Because of ICAO definitions, LPV is not considered a precision approach, even though it may have exactly the same DA as an ILS. The LPV and LNAV/VNAV go by the APV moniker, Approach with vertical guidance. In the US and I suspect the rest of the world, the APV approaches are designed with the intention of the GS being used both to the DA and below the DA to the threshold. The LNAV procedures don't make provisions for a GS and the LNAV+V is an invention of the WAAS GPS manufacturer, not the approach procedure designer. As such, there is absolutely no guarantee that the advisory glidepath will not take one into an obstacle, once below the MDA. In the US, the vertically guided procedure with a DA permits the decision to be made at the DA and that it is permitted for the aircraft to descend below the DA (sink thru) due to momentum as long as the pilot has commenced the missed approach go around at the DA if they don't spot the runway. There is no sink thru permitted for a MDA on the +V. For the airlines who's op-specs permit using the MDA as a DA, they usually are required to increase the MDA by 50 feet.

The WAAS +V GS is constructed by drawing a straight line between the FAF at the minimum altitude to the threshold at the threshold crossing altitude. I have an example in the US where it takes you 100 feet below a ridge line between the MDA and the threshold to illustrate the point that it should not be used below the MDA. Obstacles such as towers and individual trees are difficult to see in low visibility conditions and particularly at night. Many of these airports that only have LNAV procedures also do not have approach lighting systems and it more difficult to locate the runway. Many an aircraft have spotted a shopping mall parking lot and thought they had the runway under these conditions. My advice is to stay at the safety of the MDA until the runway is clearly in sight.

KUZA

UK CAA consultation on the wider use of GPS approaches

here

Introduction

Current CAA policy requires that the operator of a UK licensed aerodrome wishing to offer an instrument approach must have a runway which meets the criteria laid down in CAP 168 Licensing of Aerodromes (i.e. a non-precision or precision ’instrument runway’). A further requirement is that an Approach Control service must be provided in accordance with ANO Article 172. These regulatory requirements have stood the test of time and continue to provide a degree of ‘standards-based’ protection against the main safety risks associated with making instrument approaches.

A cross-CAA working group has evaluated the issues associated with the approval of Instrument Approach Procedures (IAPs) at aerodromes where satisfying some or all of these existing standards is not reasonably practicable and where safety can be assured using alternative mitigations. The CAA, accordingly, proposes to introduce a risk-based application process for the introduction of IAPs under such circumstances on a case-by-case basis using safety assurance activity undertaken by the applicant. The proposed policy and associated guidance on application procedures are to be outlined in a new CAP, a draft of which is now to be the subject of consultation. Comment on the draft CAP is now sought by the CAA from interested parties.

Purpose

The objective of this draft CAP is to recommend a way forward which would allow wider deployment of IAPs at UK aerodromes whilst providing continuing assurance regarding acceptable levels of safety and utilising to the greatest extent possible extant policy.

About time!

Administrator
Shoreham EGKA, United Kingdom

Having read the draft CAP I have to say it is a fairly progressive document.

EGTK Oxford

There is going to be resistance from established businesses. For example this was posted by one airport manager elsewhere

In practice, I'm not going to be overly impressed if my competitors are able to bypass the significant commercial hurdles I need to jump through each year to do the job properly. This week, I'll be spending £4k on my annual check survey, having spent £5k on tree surgery. I spent £19k having an approach designed recently and I need to buy a £14k ceilometer soon because I have a precision approach aid. This is on top of the £2k calibration costs of the other met. kit. Don't get me started on ATC costs...

But that is always the case with any deregulation. Those who complied with the regulation previously do not want deregulation. I see the same in my business (electronics) where the trade mags have regular articles from e.g. certification consultants saying how regulation is a good thing and how you can profit from it.

I think this is a great CAA initiative which will help counter the extremely damaging effect of UK's privatisation of ATC, the lack of treatment of airports as a part of the transport infrastructure, and the cost recovery principles that have always crippled the development of useful facilites for GA.

Is there any country in Europe that uses self separation on the approach i.e. does not require an approach controller to clear the pilot for the approach?

Administrator
Shoreham EGKA, United Kingdom

Is there any country in Europe that uses self separation on the approach i.e. does not require an approach controller to clear the pilot for the approach?

Here in the US, all approaches require an ATC controller to clear the aircraft for an approach, even if the approach is to a un-towered airport. After the approach clearance is issued and usually well prior to the FAF, the pilot is given instructions to contact the local frequency and to report the cancellation of the IFR clearance on the ground by remote radio, telephone, or in the air if possible.

Most non-towered airports have class G airspace beginning at 700 AGL down to the ground and VFR in this airspace is legal with 1 mile visibility and clear of clouds, so once one is clear of the clouds, VFR traffic is possible and an aircraft on an IFR clearance must use see and avoid to separate themselves from any VFR traffic. Above the class G at 700 AGL, is class E and VFR minimums require the visibility to be 3 miles, 500 foot below, 1000 feet above, and 2000 feet laterally for cloud separation. Flying in and around the airport located in Class G airspace requires all turns in the pattern to be to the left unless the airport is designated as right hand traffic. If the IFR pilot circles to land, they must obey the VFR traffic direction. In all cases, standard procedure is to use the local designated CTAF frequency (Common Traffic Advisory Frequency) and communicate with aircraft in the pattern and broadcasting position reports in the blind, example - 5 mile straight in, left down wind, base, final, ...

A very few non-towered airports have Class E all the way to the surface. This strengthens the VFR requirement and cloud separation standards. If I was king of the US, I would make all airports with instrument approaches be of this type. Although most pilots won't fly in 1 mile visibility, they jealously guard their privilege to do so, so this is unlikely to happen. They also point to the lack of any record of mid air collisions between VFR and IFR traffic in these low visibility situations to bolster their point, why try to solve a problem that doesn't exist.

KUZA

A very few non-towered airports have Class E all the way to the surface. This strengthens the VFR requirement and cloud separation standards. If I was king of the US, I would make all airports with instrument approaches be of this type.

A lot of IFR pilots over here would like that too, because it automatically makes it illegal to fly in IMC through some airport's approach path.

They also point to the lack of any record of mid air collisions between VFR and IFR traffic in these low visibility situations to bolster their point, why try to solve a problem that doesn't exist.

Same here. It's scary when it happens, and I've had a few but all the ones I saw were in VMC - obviously I have broken off a couple of approaches while in IMC (climbed back up above the cloud) due to a TCAS contact, but it was always a Mode A only contact i.e. no altitude, so again hard to make a case for that because he was probably at 500ft AGL... and there are zero midairs in these situations. All UK midairs post-WW2 were in VMC and most very low level (below 1500ft) near aerodromes. One I recall was against a twin flying an ILS...

Administrator
Shoreham EGKA, United Kingdom

I think this is a welcome initiative. I'm not convinced that the implementation will be as easy as some think but for airfields like ourselves (EGTB - Wycombe Air Park), it does create a number of opportunities. For example, one major hurdle we currently have is runway length/width, being somewhat shy of the 800m currently expected. I think the major sticking point will be this continued desire to have some form of IFR/IFR sequencing. I think the CAA need to get their heads around how this can be mitigated.

Overall, good news.

Fly safely
Various UK. Operate throughout Europe and Middle East, United Kingdom

The consultation is excellent news and long overdue. I'm pleased the CAA is going ahead with it at last.

In practice, I'm not going to be overly impressed if my competitors are able to bypass the significant commercial hurdles I need to jump through each year to do the job properly.

Is this some airport manager writing from Manchester Airports Group or Heathrow Airports Limited or Global Infrastructure Partners?

Having competition is good. Their stronghold of £100+ mandatory handling monopoly cartel of IFR ready airports must be resisted by boosting supply.

There's already some competition for flight in VFR conditions at the moment so enabling IFR flights to reach more airports must be good thing.

Perhaps this operations manager should look at how he should cut regulatory red tape at his own airport with the relevant authorities to keep it more competitive instead of looking to pay huge bonuses to his executive team, health and safety jobsworths, and his investors....

UK trial of LPV in Class G, no ATC

According to a presentation at the show at Sywell, Booker / High Wycombe (EGTB) will be getting a trial LPV procedure.

EGTB is in Class G and this clever move is what enables a non-ATC airfield to have an IAP – because no IFR clearance is required and in fact none is even possible.

I have no idea how they are going to schedule traffic onto the approach. It could be self-announcement. IMHO it is highly unlikely to be the US-style of a remotely located approach controller – due to the UK’s cost recovery principle this would cost the airfield far too much. It is also unlikely that the man on the ground (a FISO, I believe) will be doing it because a non-ATCO has no power over airborne traffic, and I would expect the ATC unions to raise hell if this was tried (though IMHO they could not actually prevent it). But I am just guessing.

This is very good news.

I don’t know if the runway meets ICAO “instrument runway” specs but clearly that can be practically addressed with a suitable choice of minima.

Administrator
Shoreham EGKA, United Kingdom

Funnily enough, Wycombe is a field with ATCO’s

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