Primarily for general aviation discussion, but other aviation topics are also welcome.
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By fattony
#1519820
I had always thought that IAPs were prohibited in the UK unless ATC was in place at the airfield - mainly due to stuff I read on here and other forums. However, CAP 797 seems to suggest otherwise. In particular, it talks about FISOs providing an air traffic service to aircraft conducting instrument approaches on page 70 paragraph 8.11, page 84 paragraph 8.87 and section 12 on page 99.

Section 12 of CAP 797 mentions CAP 1122, which is called "Application for instrument approach procedures to aerodromes without an instrument runway and/or approach control". That also seems to suggest ATC isn't mandatory for an instrument approach.

So, my question: why don't we have IAPs without full ATC? Or am I simply misinformed?
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By Iceman
#1519848
joe-fbs wrote:But, AIUI, having researched this for work a few months ago, limited to approved users where it is a community service operation (or words to that effect).


There is nothing in the AIP entry / plates for Barra, for instance, that indicates such a restriction.

Iceman 8)
#1519853
fattony wrote:So, my question: why don't we have IAPs without full ATC? Or am I simply misinformed?

Money.
First you have to get it designed by an approved iap design company,(no you can't do a diy design) then you have to get it approved by the CAA along with a 'Safety Case' to ensure f'rinstance that you don't get more than one pilot trying to fly the approach at a time and procedures to ensure the approach does not become dangerous if the guidance signal is lost, plus a missed approach procedure usually involving another type of navaid.
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By Iceman
#1519859
Elecy wrote:There is a comment "Use of RNAV procedure at this aerodrome restricted to Highlands and Islands Airports Ltd - Approved Operators only." on the approach plate for Barra.

Mark


Oh yes, just spotted it.

Iceman 8)
#1519908
When employed by the CAA, I helped develop the policy leading to publishing CAP1122.

It took years to accomplish starting with the LNAV trial at Shoreham. The availability of European funding has helped accelerate the introduction of LPV approaches but there is still much work to do.

There are challenges to achieving approval at AFISO units not part of Scottish Public Service Obligated routes under EU Regulation (EC) No 1008/2008 but it should be possible under current CAA Policy.

I'm one of a very small number helping some organisations make real progress towards the establishment of RNAV(GNSS) IAPs, though I won't be naming them here.

Should any forumites need more info feel free to pm me.
#1519953
chevvron wrote:
fattony wrote:So, my question: why don't we have IAPs without full ATC? Or am I simply misinformed?

Money.
First you have to get it designed by an approved iap design company,(no you can't do a diy design) then you have to get it approved by the CAA along with a 'Safety Case' to ensure f'rinstance that you don't get more than one pilot trying to fly the approach at a time and procedures to ensure the approach does not become dangerous if the guidance signal is lost, plus a missed approach procedure usually involving another type of navaid.

An approach is really nothing more than defining a descending line that follows the extended centre line of the runway and intersects it at the threshold. Given GPS, writing some software to produce a pseudo ILS to guide you along that line isn't difficult. The GPS in my phone is good enough to show what side of the road I'm driving on and, while it's not quite so good in height, is still pretty good. I could write an app for my phone that directed me to a runway and, with a minimum of something like 500' QFE, should give time to sort out a sensible visual landing. The failed approach procedure consists of climbing to MSA and going somewhere sensible.

I realise that this doesn't cover everything and would be illegal but how many people's lives could have been saved with something like this? I can think of five in the last year or so.
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By Josh
#1519958
There is an App that does that. It's called GPS ILS, and one of its biggest advocates wrote off his aircraft in **** IFR conditions in the Scillies and may or may not have been using it at the time.

It is my strong view that pilots conducting DIY approaches in any form Are auditioning for a Darwin Award.
AndyR liked this
User avatar
By Gertie
#1519960
ChrisRowland wrote:I realise that this doesn't cover everything and would be illegal but how many people's lives could have been saved with something like this?

And how many have been lost by using something like this?
#1519965
Gertie wrote:
ChrisRowland wrote:I realise that this doesn't cover everything and would be illegal but how many people's lives could have been saved with something like this?

And how many have been lost by using something like this?

Tell us how many you think.

The guy at the Scillies seems to have ended up coming in far too fast, possibly downwind. Would any ILS approach would have compensated for that?
#1520081
[quote="ChrisRowland"
An approach is really nothing more than defining a descending line that follows the extended centre line of the runway and intersects it at the threshold. Given GPS, writing some software to produce a pseudo ILS to guide you along that line isn't difficult. The GPS in my phone is good enough to show what side of the road I'm driving on and, while it's not quite so good in height, is still pretty good. I could write an app for my phone that directed me to a runway and, with a minimum of something like 500' QFE, should give time to sort out a sensible visual landing. The failed approach procedure consists of climbing to MSA and going somewhere sensible.

[/quote]
And following a line you have drawn guarantees the necessary terrain clearance does it?