Unpublished let-downs
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Irrespective of the finer arguments of the legal position, it is sobering to remember history suggests enforcement by terrain is more usual than enforcement by the relevant authorities.
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Bookworm
That is not something that anybody has taken issue with. Nonetheless the rules on aerodrome operating minima do also exist.
A point already made by many posters. So far the nearest anyone has come to disagreeing with it are the posters including yourself who think homebrew approaches are perfectly legit.
According to you. But the regulations and the CAA guidance I have quoted above tell a different story.
By your logic you can descend from safety altitude 'for the purpose of landing', without following any approved procedure and therefore not observe any further minimums below that point. But the regulations say you have to obey the aerodrome operating minima which in turn has to be approved by the state. Equally, by your logic, it would be legal to descend from safety altitude on some half baked procedure, then pick up a published approach, then arrive at minimums without the required visual references and still legally continue, merely because it was 'for the purpose of landing'. What a nonsense.
The 1000 ft mentioned in (b) is not part of "aerodrome operating minima". It is a generic rule for IFR flight that applies except when necessary for take-off or landing.
Descent below the levels addressed in SERA.5015(b)(2) when taking off or landing is not to be taken lightly. The best way of mitigating risk is to use a PANS-OPS compliant instrument approach procedure if available.
But there is no requirement that a published procedure is used to meet the requirements of SERA.5015(b) when operating under Part-NCO.
By your logic you can descend from safety altitude 'for the purpose of landing', without following any approved procedure and therefore not observe any further minimums below that point. But the regulations say you have to obey the aerodrome operating minima which in turn has to be approved by the state. Equally, by your logic, it would be legal to descend from safety altitude on some half baked procedure, then pick up a published approach, then arrive at minimums without the required visual references and still legally continue, merely because it was 'for the purpose of landing'. What a nonsense.
Last edited by oggers; 3rd Feb 2017 at 17:18.
But the regulations say you have to obey the aerodrome operating minima which in turn has to be approved by the state.
Equally, by your logic, it would be legal to descend from safety altitude on some half baked procedure, then pick up a published approach,
[then arrive at minimums without the required visual references and still legally continue, merely because it was 'for the purpose of landing'.
NCO.OP.210 Commencement and continuation of approach — aeroplanes and helicopters
(a) The pilot-in-command may commence an instrument approach regardless of the reported runway visual range/visibility (RVR/VIS).
(b) If the reported RVR/VIS is less than the applicable minimum, the approach shall not be continued:
(1) below 1 000 ft above the aerodrome; or
(2) into the final approach segment in the case where the decision altitude/height (DA/H) or minimum descent altitude/height (MDA/H) is more than 1 000 ft above the aerodrome.
(c) Where the RVR is not available, RVR values may be derived by converting the reported visibility.
(d) If, after passing 1 000 ft above the aerodrome, the reported RVR/VIS falls below the applicable minimum, the approach may be continued to DA/H or MDA/H.
(e) The approach may be continued below DA/H or MDA/H and the landing may be completed provided that the visual reference adequate for the type of approach operation and for the intended runway is established at the DA/H or MDA/H and is maintained.
(f) The touchdown zone RVR shall always be controlling.
In a country where the state pays for countless IAPs to small airports, I can just about understand a rule that makes their use obligatory. In the UK approval and publication of an approach procedure offers significant value in mitigating risk. But that does not mean that a trajectory to landing without that £30,000 stamp of approval is not safe enough.
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Bookworm, thanks for providing relevant quotes.
tmmoris, precisely.
Some forget that company Ops manuals are not necessarily the same as the legal requirement.
The term "should" does not denote a legal requirement, it's a recommendation. The term "shall" denotes the former.
I have absolutely no intention of killing myself, or anyone else. But thanks for your advice anyway.
tmmoris, precisely.
Some forget that company Ops manuals are not necessarily the same as the legal requirement.
The term "should" does not denote a legal requirement, it's a recommendation. The term "shall" denotes the former.
I have absolutely no intention of killing myself, or anyone else. But thanks for your advice anyway.
This old chestnut of 'for the purpose of landing' crops up time and again from one particular group...
Anyway, here's what the UK IAIP states:
No doubt some barrack room lawyer will now jump up and say that the UK IAIP isn't actually a legal instrument, so this is only 'guidance' 
Anyway, here's what the UK IAIP states:
4.12 Aerodromes Without Published Instrument Approach Procedures
4.12.1 For an aircraft landing at an aerodrome without an instrument approach procedure either:
4.12.1 For an aircraft landing at an aerodrome without an instrument approach procedure either:
(a) a descent should be made in VMC until in visual contact with the ground, then fly to the destination; or
(b) an IAP at a nearby aerodrome should be flown and proceed as in (a); or
(c) if neither (a) nor (b) is possible, first obtain an accurate fix and then descend not lower than 1,000 ft above the highest obstacle within 5 NM (8 km) of the aircraft. If visual contact (as at (a) above) has not been established at this height, the aircraft should divert to a suitable alternate with a published instrument approach procedure.
(b) an IAP at a nearby aerodrome should be flown and proceed as in (a); or
(c) if neither (a) nor (b) is possible, first obtain an accurate fix and then descend not lower than 1,000 ft above the highest obstacle within 5 NM (8 km) of the aircraft. If visual contact (as at (a) above) has not been established at this height, the aircraft should divert to a suitable alternate with a published instrument approach procedure.
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Beagle, I'm no barrack room lawyer but again, the term "should" has never been used by the UK CAA to denote a mandatory action. The term "shall" has always been used for that purpose, as you will no doubt recall. It is important to understand the difference.
Not my personal interpretation, but that of the CAA.
Edit: For the benefit of those who like quotes, I dug out my copy of "Aviation Law For Pilots", which dates back to 1971. At the time I was studying for my commercial licence (late 1980s) this was the CAA recommended study guide. I remember taking their advice and pre-ordered the impending new sixth edition so it was bang up to date and had to drive quite along way to collect it!
Section 1 is VFR/IFR and a summary "tree" is on page 3.
Quote (carefully copied word for word):
IFR
If the flight is INSIDE CONTROLLED AIRSPACE
The pilot must comply with the following requirements:
1. He must hold an Instrument Rating.
2. He must file a flight plan with the appropriate ATC.
3. He must obtain ATC clearance to proceed or to enter the airspace and he must obey the instructions.
4. He must make position reports in accordance with notified procedures or as required by the appropriate ATCC.
5. Unless he is on a notified route, taking off/landing or authorised otherwise by an ATSU, he must maintain adequate ground clearance, i.e. clearance by 1000 ft (minimum) of the highest obstacle within 5 nm of the aircraft.
(and)
If the flight is OUTSIDE CONTROLLED AIRSPACE
at 3000 ft amsl and below
1. Fly at least 1000 ft above the highest obstacle within 5nm of the aircraft, unless the aircraft is clear of cloud and in sight of the surface, or is on a notified route or taking off/landing or authorised by an ATSU.
Obviously some things have changed since then; for a start we have women pilots (!) and we have gone over to the metric system and via JAR to SERA. However, the same principle has been maintained.
Not my personal interpretation, but that of the CAA.
Edit: For the benefit of those who like quotes, I dug out my copy of "Aviation Law For Pilots", which dates back to 1971. At the time I was studying for my commercial licence (late 1980s) this was the CAA recommended study guide. I remember taking their advice and pre-ordered the impending new sixth edition so it was bang up to date and had to drive quite along way to collect it!
Section 1 is VFR/IFR and a summary "tree" is on page 3.
Quote (carefully copied word for word):
IFR
If the flight is INSIDE CONTROLLED AIRSPACE
The pilot must comply with the following requirements:
1. He must hold an Instrument Rating.
2. He must file a flight plan with the appropriate ATC.
3. He must obtain ATC clearance to proceed or to enter the airspace and he must obey the instructions.
4. He must make position reports in accordance with notified procedures or as required by the appropriate ATCC.
5. Unless he is on a notified route, taking off/landing or authorised otherwise by an ATSU, he must maintain adequate ground clearance, i.e. clearance by 1000 ft (minimum) of the highest obstacle within 5 nm of the aircraft.
(and)
If the flight is OUTSIDE CONTROLLED AIRSPACE
at 3000 ft amsl and below
1. Fly at least 1000 ft above the highest obstacle within 5nm of the aircraft, unless the aircraft is clear of cloud and in sight of the surface, or is on a notified route or taking off/landing or authorised by an ATSU.
Obviously some things have changed since then; for a start we have women pilots (!) and we have gone over to the metric system and via JAR to SERA. However, the same principle has been maintained.
Last edited by ShyTorque; 4th Feb 2017 at 09:14.
While 'Shall' denotes a mandatory requirement, the word 'should' expresses a recommendation or advice. Such recommendations or advice are expected to be followed unless satisfactory reasons are stated for not doing so.
Which is why, for example, one is expected to follow AMC/GM (in which 'shall' is never used) unless a derogation or an AltMoC is in place.
Which is why, for example, one is expected to follow AMC/GM (in which 'shall' is never used) unless a derogation or an AltMoC is in place.
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Unpublished procedures are used in numerous places I can think of and have been used safely by some pilots for decades
The thing that few admit or of course they were visual
This isn't a statement on whether they should be done or not just an ackowlegemrnt that they are
Just because it published that makes it safe
If it's not published it's not safe ?
One recommendation above is letting down at an airport with a published procedure and going to your destination below
The most dangerous procedure is low level scud running with low cloud and poor visibility
I can remember decades back flying to Caernarfon it was common practice to cross the mountains in IMC fly over the NDB and then let down over the sea I suppose that's a non published procedure
I am sure we would all love to Lock onto a nice ILS but sadly smaller airfields are not so equipt! The have to fly brigade concoct all manner of solutions and always have For as long as I can remember
So it's probably something publicly shunned but privately ??
The thing that few admit or of course they were visual
This isn't a statement on whether they should be done or not just an ackowlegemrnt that they are
Just because it published that makes it safe
If it's not published it's not safe ?
One recommendation above is letting down at an airport with a published procedure and going to your destination below
The most dangerous procedure is low level scud running with low cloud and poor visibility
I can remember decades back flying to Caernarfon it was common practice to cross the mountains in IMC fly over the NDB and then let down over the sea I suppose that's a non published procedure
I am sure we would all love to Lock onto a nice ILS but sadly smaller airfields are not so equipt! The have to fly brigade concoct all manner of solutions and always have For as long as I can remember
So it's probably something publicly shunned but privately ??
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While 'Shall' denotes a mandatory requirement, the word 'should' expresses a recommendation or advice. Such recommendations or advice are expected to be followed unless satisfactory reasons are stated for not doing so.
Which is why, for example, one is expected to follow AMC/GM (in which 'shall' is never used) unless a derogation or an AltMoC is in place.
Which is why, for example, one is expected to follow AMC/GM (in which 'shall' is never used) unless a derogation or an AltMoC is in place.
As Pace wrote, not everyone has the luxury of operating from an ILS equipped, fully lit airfield.
For those in any doubt as to the CAA's position over the legalities (over and above the sensibilities) of this subject, this fairly recent AAIB report, which includes CAA input, hopefully makes it clear. It was referred to earlier by Sir Niall Dementia.
https://www.gov.uk/aaib-reports/aaib...y-s-76c-g-wiwi
AMC/GM
)In the 2014 AOC rewrite due to EASA law changes it was mandated that "should" references in the manuals be changed to "shall" - there were hundreds of them.
As for unpublished let downs with GPS ..... having studied TERPS and PANS-OPS I think most people would be shocked, given the accuracy of the aids, at the "protection" available at certain stages of a non-precision approach not withstanding it was over mountainous terrain at night on the coast with the aid not co-located with the airport .... I know what I'd rather have.
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Fascinating thread.
Isn't it true that in the real world of (non commercial) flying pilots do whatever the heck they want ? They are only normally held accountable when something goes wrong, which thankfully doesn't happen often. And of course it is difficult to argue why you did something when you're six feet under ("but St Peter[insert personal faith equivalent], I was in visual contact with the ground ....").
That is why there are those that fly in IMC without a rating, in planes not certified for IMC, sometimes with a lapsed licence/medical/insurance.
I'm not going to argue with any of the legal interpretations above, FWIW given my training and experience (IR(R), with less than a dozen 'real' (i.e. non training) instrument approaches logged) I wouldn't fly an unapproved one, legal or not.
Isn't it true that in the real world of (non commercial) flying pilots do whatever the heck they want ? They are only normally held accountable when something goes wrong, which thankfully doesn't happen often. And of course it is difficult to argue why you did something when you're six feet under ("but St Peter[insert personal faith equivalent], I was in visual contact with the ground ....").
That is why there are those that fly in IMC without a rating, in planes not certified for IMC, sometimes with a lapsed licence/medical/insurance.
I'm not going to argue with any of the legal interpretations above, FWIW given my training and experience (IR(R), with less than a dozen 'real' (i.e. non training) instrument approaches logged) I wouldn't fly an unapproved one, legal or not.
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Beagle,
That's exactly why I posted my reply and we obviously agree on that point. But the discussion I entered was with regard to the legality of a descent from the required "1,000 ft above" under IFR in order to land. Some here have stated that it has never been legal except on a published let down. The CAA, now our "Competent Authority" do not presently agree with that statement and as far as I can tell, have never historically decreed it illegal, although the documentation I have to hand only goes back 45 years or so. 
While 'Shall' denotes a mandatory requirement, the word 'should' expresses a recommendation or advice.
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ShyTorque
The argument is not about what happened going back 45 years. Early on it was established that it most certainly used to be 'legal'. The problem is you believe that it is still legal for GA pilots to carry out unapproved let downs below safety altitude.
In your opinion. But in the CAA's opinion:
as far as I can tell, [the CAA] have never historically decreed it illegal, although the documentation I have to hand only goes back 45 years or so.
Some here have stated that it has never been legal except on a published let down. The CAA, now our "Competent Authority" do not presently agree with that statement
User-defined approaches can be dangerous and are not authorised
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Bookworm, I wrote:
You wrote:
But it is. The minimum vectoring altitude is not below safety altitude. The only time you would be vectored below the 1000' obstacle clearance is when on final of a radar approach (but even then you will still be getting the required obstacle clearance).
by your logic, it would be legal to descend from safety altitude on some half baked procedure, then pick up a published approach
So far so good -- that's not significantly different from vectoring.
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Oggers, read the AAIB report. It's not my opinion - it's there in black and white (actually, black and pink in the report, for the more argumentative ones among us)!
Safety Recommendation 2014-35
It is recommended that the Civil Aviation Authority review the regulations that
permit a helicopter engaged in public transport operations to descend below
MSA for the purpose of landing, when flying in instrument meteorological
conditions but not on a published approach procedure.
It is recommended that the Civil Aviation Authority review the regulations that
permit a helicopter engaged in public transport operations to descend below
MSA for the purpose of landing, when flying in instrument meteorological
conditions but not on a published approach procedure.
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Oggers,
Here is the relevant "present" rule (copied direct from the CAA website which links to a .PDF):
The problem is you believe that it is still legal for GA pilots to carry out unapproved let downs below safety altitude.
SERA.5015 Instrument Flight Rules (IFR) - Rules Applicable to All IFR Flights
(a) Aircraft Equipment
Aircraft shall be equipped with suitable instruments and with navigation equipment appropriate to the route to be flown and in accordance with the applicable air operations legislation.
(b) Minimum Levels
Except when necessary for take-off or landing, or except when specifically authorised by the competent authority, an IFR flight shall be flown at a level which is not below the minimum flight altitude established by the State whose territory is overflown, or, where no such minimum flight altitude has been established:
(1) over high terrain or in mountainous areas, at a level which is at least 600 m (2 000 ft) above the highest obstacle located within 8 km of the estimated position of the aircraft;
(2) elsewhere than as specified in a), at a level which is at least 300 m (1 000 ft) above the highest obstacle located within 8 km of the estimated position of the aircraft.
(a) Aircraft Equipment
Aircraft shall be equipped with suitable instruments and with navigation equipment appropriate to the route to be flown and in accordance with the applicable air operations legislation.
(b) Minimum Levels
Except when necessary for take-off or landing, or except when specifically authorised by the competent authority, an IFR flight shall be flown at a level which is not below the minimum flight altitude established by the State whose territory is overflown, or, where no such minimum flight altitude has been established:
(1) over high terrain or in mountainous areas, at a level which is at least 600 m (2 000 ft) above the highest obstacle located within 8 km of the estimated position of the aircraft;
(2) elsewhere than as specified in a), at a level which is at least 300 m (1 000 ft) above the highest obstacle located within 8 km of the estimated position of the aircraft.
Terrain clearance reduces to 500ft when being vestored for any type of iap provided the CAA have approved an 'imntermediate approach area' on your SMAC. Ths ONLY applies to being radar vectored however not to self positioning.
But it is. The minimum vectoring altitude is not below safety altitude. The only time you would be vectored below the 1000' obstacle clearance is when on final of a radar approach (but even then you will still be getting the required obstacle clearance).
Equally, by your logic, it would be legal to descend from safety altitude on some half baked procedure, then pick up a published approach, then arrive at minimums without the required visual references and still legally continue, merely because it was 'for the purpose of landing'.