Unpublished let-downs

[TooL8]

I'd like to start up a discussion on unpublished or 'home-grown' instrument let-downs.

Many of uf with IR or IR(R) find ourselves at local airfields with no published procedures. Arriving VMC on top with 8/8 below, a diversion to the nearest published procedure is obviously the 'correct' exam answer; but real-world, many of us will letdown to MSA on a VOR radial or GPS position (RAIM checked;)).

The recent fatality in Oxofdshire thread raises doubt as to the long term safety of this practice (it's mentioned in one of the threads). Can I question this? If accurately flown, with stations tuned, identified and 'flags away' and or GPS RAIM checked, what do we think are the risks?

Collision with other acft is a given. Would a traffic service be mitigate risk sufficiently? What does everyone think?

[chevvron]

When designing an iap, ICAO requires various 'extra' factors to be considered when calculating the minima eg terrain clearance in the missed approach area, type of approach and runway lighting.
Many people don't know this and just base their minima on the 'lowest possible' for that type of approach.
For instance, many years ago I got out the ICAO manual and tried to design an NDB/DME procedure for runway 26 (now runway 25) at Blackbushe. Although the lowest permissible minimum for this type of iap would be 250ft QFE, the minima taking all other required factors into account came to 620ft QFE.

[piperboy84]

I designed a "homemade" approach to my grass strip a few years back and flew it many times in VFR conditions, it was loaded on the panel mounted Garmin 496 with an external antenna so was pretty much rock solid. I kept refining then flying it always in VFR conditions over and over again till I had it nailed. Then the first day I went to try it in actual I was lined up 15 miles out on final at 4500 ft with the overcast between 1000 msl (750 AGL) topping out at 3000 and I started my descent for the soup. Just before entering i thought to myself f:mad:K this! powered up, turned south and headed 15 miles out to sea, picked up the Leuchars ILS and rode it down to VFR then flew back to my strip low level with plenty of head height/ground clearance from the ceiling.

Bottom line, it just ain't worth it.

Edit to add, I had the GPS with the signal and accuracy alarms set which would pipe an audible warning thru the audio panel to my headset. Still didn't feel confident

[2 sheds]

TooL8
You mention descent to MSA, which is fine, but you start the thread by referring to "unpublished or 'home-grown' instrument let-downs" which is a worry and could subsequently comprise part of an accident report.
Of course a Traffic Service would reduce the risk - but whether "sufficiently", that's your guess! By the very nature of what you are suggesting, at or around MSA (and it depends on the ATC unit's agreed "terrain safe level") you would find yourself being told "take own terrain clearance" - and also probably "reduced traffic information due to the limits of surveillance coverage."

2 s

[sapperkenno]

Having flown a lot in and around Phoenix, Arizona, the prevalence of GPS/RNAV approaches (even 10 years ago), in a state well known for hardly ever having poor weather... almost every airfield with any sort of published approaches had one. From the smallest private air park to almost every municipal airfield as well as Sky Harbor.
I won't go on too much about training and being tested on GPS approaches during my US instrument rating, and more recently doing my EASA CBIR have to re-learn 20 ways to skin a cat and fly a textbook NDB hold - with no mention of GPS, and this despite training on a G1000. :ugh:
Now having worked as an FI in the northern U.K. for the last 4 years, I know only of Blackpool, and I think Manchester in this neck of the woods that have these procedures... Sherburn and Leeds East keep promising their's, which never seem to come.

The problem wouldn't happen to be our CAA now would it, and the massive costs to approve such approaches?

To answer your "what does everyone think" I'd say the problem lies with our legislators and their archaic ideas of what should be trained/tested for the instrument rating, and how much they charge to approve such procedures... much easier to prohibit GA further, and stick to systems which in all fairness aren't broke, so don't really need fixing! As long as CAT is looked after, and only a few GA pilots are killing themselves every few years, and not wiping out loads of people on the ground, nothing will change.

[ChickenHouse]

Nice question, but when I started thinking, I immediately felt a lack of information!

Anybody here firm on details how "published" let-downs are done?

What are the steps to let us assign a quality flag and what do we exactly gain on the "this is a published approach"?

Yes, a clerk at his table and a crew in an official aircraft, measuring approaches twice a year in VMC, do have the responsibility to do their job right, but they also have the "get out of jail for free card" when just following written procedures.

But no, on the other side I have the ultimate accountability sitting left seat and if I fail, I die. If I build a personal let-down based on daily ops at a specific airfield, will it do better or worse than the published, for me and/or others using it?

What does this tell us about the potential quality of approach let-downs? I.e. if I know I have to cut that corner 10 degrees left, because I always have the tendency to do this and that, I gain a personal let-down for my skills. Does a "published" approach gain additional safety margin, because the measure will be "the average pilot"?

The longer I think about, the more complicated the original question gets.

[oggers]

Descending to safety altitude (and not below) for a look is okay. Continuing below safety altitude on an unpublished home grown procedure is not something that anyone should be doing except as a last resort in an emergency. It should certainly not be done to avoid:

a diversion to the nearest published procedure

[JW411]

Many years ago, I used to operate from a strip in Germany with no aids. A friend devised a home-made letdown based on a nearby VOR/DME. I seem to remember that he had worked out that an MDH of 500 feet AGL was safe. One day he came down through the murk and was delighted to see the strip nicely on the nose when he broke out at around 600 feet. His joy was short lived; seconds later two NATO F-104s rocketed underneath him on a reciprocal track! An immediate landing for an underpants change became his first priority.

[Sillert,V.I.]

I'd like to start up a discussion on unpublished or 'home-grown' instrument let-downs.


This is something which I have done a long time ago, but wouldn't do now.

Descent to MSA requires mitigating only the air-to-air collision risk and a basic radar service should take care of that. Descent below MSA requires mitigating the CFIT risk and IMO that is far more likely to happen in the real world.

Unfortunately to get the job done, descent below MSA is usually required and although we all know this is something thou shalt not do, I suspect the practice sometimes happens.

The temptation may be greater today than it was when I started flying in the '80's; there are fewer viable, affordable, GA friendly options for using airfields with published procedures now.

Availability of moving-map displays, both certified and otherwise, may also increase temptation and risk, without properly mitigating the inherent danger.

I wouldn't wish to see anything posted here which could be construed by my younger self as encoraging this practice.

In short, please don't do it. Your life is precious and you have only one, something I have become increasingly aware of with advancing years.

Stay safe out there.

[2 sheds]

a basic radar service should take care of that


Presumably you mean a Traffic Service (in the UK) ? There has never been a "Basic Radar Service". But see #5 above.


2 s

[alex90]

I was under the impression that Instrument Flight Procedures for RNAV/GNSS approaches were now considerably more accessible than they once were. I have been told that having a GNSS approach would considerably reduce the cost of running and maintaining real beacons, but more importantly, that these approaches were not as expensive as first thought to get approved.

I remember being given a ballpark (which stayed in my mind for some time), in the order of £40-50k for the airport survey, IFP GNSS design, UK CAA paperwork, validation flight, risk assessment, proposition for airspace changes, CAA charges and risk assessments. For 2 reciprocating runways.

I assume that these costs vary wildly depending on many many factors of course, but at a cost of £50k the question is: How much do you value using an airport / aerodrome on days where clouds are at or below MSA - if this is of high value - how much do you value your life? And how much have you spent on your aeroplane? Is it worth invalidating your insurance to attempt the descent? Surely just a small group of owners could easily get together at smaller fields to purchase a published instrument approach - maybe even striking a deal with the airfield re: landing fees being waved or IFR approach fees being paid back to them when it has been used by others... etc...

I would not descend below MSA, unless in an emergency of course (ie: engine failure) if I was not on an approach! I would seriously question the sanity of anyone who would!!

[Pittsextra]

descent below MSA on approach or at some other time surely just requires one to be certain of ones position? If you can achieve that then it becomes less astonishing doesn't it?

[Gertrude the Wombat]

surely just requires one to be certain of ones position
... which you never can be, exactly, which is why approaches need designing to acceptable inaccuracy limits, with get-outs when things go pear-shaped, ect ect ...

[Pittsextra]

sure no truck with that argument but to be clear if the issue is positional error and as you rightly say an acceptable margin then that can/could be done regardless of someone in an office deciding so. An individual could be quite capable of achieving something quite flyable.

[piperboy84]

I'd imagine a lot more folks will be trying descent below MSA now that Garmin is selling this VFR GPS for under $1000 with synthetic vision

1633

https://buy.garmin.com/en-US/US/p/14859

[Downwind.Maddl-Land]

A similar subject was aired on the Flyer forum a while back. Taking and regurgitating one post probably explains why RNAV IAPs haven't been widely adopted in the UK, yet:

Backs of fag packets are not a UK CAA approved design tool.

The protection areas applicable to IFPs (and they are different for each type of IFP - but someone, somewhere, in ICAO did a LOT of clever mathematics to work out what those criteria might be) take into account many variables - including the concept, for example, of 'spiral winds' in which the nominal track of the aircraft is assumed to be adversely affected by the 'worst case' winds applicable to the calculated altitude throughout the turn. Consequently, the areas to be examined for obstacles would surprise you; they are far larger than you would imagine. Unfortunately, hard past experience has shown that the protection areas are not unduly conservative.

However, that is far from the whole story; its the allied: satellite coverage prediction report, increased (new?) CAP 232 survey requirements, safety case, ACP (that's the 'killer'), flight validation database production, flight validation plan, flight validation itself, etc that rack the price up. However, if you want your IAP to be Approved by SARG for promulgation in the AIP (discrete IAPs are no longer allowed) then that's what you have to do. And if you are a GA aerodrome with AFISOs, then you can include the CAP 1122 process costs as well!

The OP's post is probably a shining example of the old adage "a little knowledge can be dangerous."

[tmmorris]

Isn't the problem with GNSS approaches in the U.K. more the requirement for approach trained controllers? Whereas the USA allows you to shoot an approach to a non-towered or closed airfield with a clearance from a controller many miles away, so the only cost is the survey and approach design (and many early GPS approaches were overlays).

Question: is ILS to an airfield nearby followed by 5-10nm of scud running safer than a home made approach flown using a proper approach certified GPS direct to the runway?

(And it's Alexander Pope - 'A little learning is a dangerous thing.')

[tmmorris]

(PS I know that a nationalised ATC system and class E airspace everywhere 700 or 1200ft AGL are part of that US system too)

[piperboy84]

Question: is ILS to an airfield nearby followed by 5-10nm of scud running safer than a home made approach flown using a proper approach certified GPS direct to the runway?

I'd rather take my chances shooting a homebrew approach with a non certified but extremley feature rich and flexible GPS like a Garmin 496 than I would with a cumbersome and purpose built certified unit like a 430. In fact I'd rather use an IPAD with SD than a 430.

[Gertrude the Wombat]

(And it's Alexander Pope - 'A little learning is a dangerous thing.')
Yes. The "little knowledge" misquotation is wonderfully recursive.

[27/09]

Homebrew approaches, what an extremely stupid idea. Either fly IFR and carryout a promulagted approach or fly VFR, don't go making up your own procedures.

I'm sure there are a few clever people who can figure out something, then there are the rest of us who are not so clever and miss an important item.

One thing you cannot incorporate in a home brew GPS approach is the scaling required to give the accepted scaling requirements that occur in a promulgated GPS approach.

Isn't the problem with GNSS approaches in the U.K. more the requirement for approach trained controllers? Whereas the USA allows you to shoot an approach to a non-towered or closed airfield with a clearance from a controller many miles away, so the only cost is the survey and approach design (and many early GPS approaches were overlays).

Isn't that so quaintly British, find a difficult solution to a simple problem. What benefit does the controller provide?

In New Zealand, (and I suspect it's the same in the USA) no controller clears you for an approach located outside of controlled airspace. You will be cleared out of controlled airspace and then you will carry out the approach as promulgated in the AIP. No controller input required.

[piperboy84]

I just want to clarify my earlier post that may be misinterpreted.

i'd rather take my chances shooting a homebrew approach with a non certified but extremley feature rich and flexible gps like a garmin 496 than i would with a cumbersome and purpose built certified unit like a 430. In fact i'd rather use an ipad with sd than a 430.

this was purely hypothetical, i haven't and would never do approaches this way and would strongly advise anyone considering it not to.
I was merely commenting on the user friendliness of different guidance systems.

[Sillert,V.I.]

Question: is ILS to an airfield nearby followed by 5-10nm of scud running safer than a home made approach flown using a proper approach certified GPS direct to the runway?


It seems to me that would be a choice between two alternatives, both of which are inherently unsafe.

Descending on a published approach to a point from which you are able to proceed VFR to destination is acceptable provided you are sure you will be in VMC until you land, but I would not call that scud running.

What benefit does the controller provide?

An out if you mess up, particularly if they have radar. Suppose you lose visual reference after the MAP? The serious incident (https://www.gov.uk/aaib-reports/boeing-757-2t7-g-mone-17-march-2006) in Gibraltar with a Monarch 757 comes to mind.

[alex90]

A controller would be a great bonus - yes. But should a controller be REQUIRED? I think not...

Since when do we need full ATC support to shoot an approach. In NZ it works marvellously well to just announce yourself, and follow the procedure. What happens in the UK when controllers become unavailable? Would elf n safety make them go elsewhere? Or would they just follow the procedure and land anyway?

In the case of the monarch flight - as well as a couple more recent incidents, ATC is useful to catch people's mistakes, but surely that is always pilot error is it not? That will always happen, even with ATC!

[27/09]

Sillert,V.I: An out if you mess up, particularly if they have radar.

It would seem just having an available approach without a controller provides a level of accessibility and safety far in excess of not having an approach because you need to have a controller. One third of airfields in New Zealand that have scheduled IFR services do not have ATC of any sort. There's also plenty of others with no ATC that don't have scheduled services.

Sillert,V.I: Suppose you lose visual reference after the MAP?

Carry out the missed approach procedure, or, if more appropriate from a obstacle clearance point of view, carry out the promulgated IFR departure for that runway.

Unless it's a circling approach, I'd have to say in my experience, it would be very very unusual to lose visual reference after the MAP.

[Arfur Dent]

Find a nearby airfield with an ILS if your aircraft is so equipped. Fly a few ILS approaches in VFR until you are 'competent'. If you get caught out above 8/8 clag, divert to said airfield, fly the ILS ( be prepared to explain if you are non- IR) and get a taxi home.
Don't fly below MSA in IMC unless you are qualified. Don't "scud run". It's not fun and you could kill yourself very easily!
If you expect conditions below 3-5miles vis/1500 cloud base - think "DO I REALLY WANT TO DO THIS?".

[Downwind.Maddl-Land]

Isn't the problem with GNSS approaches in the U.K. more the requirement for approach trained controllers?

No. The advent of CAP1122 in the UK provides for IFR approaches at locations without Approach control. However, as it stands, AFISOs are a prerequisite as Air/Ground only is (currently) unlikely to get approval according to said document.

(And it's Alexander Pope - 'A little learning is a dangerous thing.')

Nice to see the focus on the really important aspects of this safety related debate.....:hmm:

[tmmorris]

Good news, actually that does ring a bell but has any airfield got even near an approach with an AFISO yet?

As for Pope - why let an inaccurate fact go unchallenged, ever? I agree it has nothing to do with safety. It's a mindset.

[Jonzarno]

Nice to see the focus on the really important aspects of this safety related debate.....

Nice to see that we can focus on this really important facet as well..........;):p

[A le Ron]

Good news, actually that does ring a bell but has any airfield got even near an approach with an AFISO yet?

As for Pope - why let an inaccurate fact go unchallenged, ever? I agree it has nothing to do with safety. It's a mindset.

The Sherburn application is, I understand, at an advanced stage with the CAA.

[Downwind.Maddl-Land]

Originally Posted by tmmorris
Good news, actually that does ring a bell but has any airfield got even near an approach with an AFISO yet?

Campbeltown, Barra, Islay, Walney Is, Tiree all published. Wolverhampton well advanced but still in the pipeline.

Lands End is Twr only; no App.

[riverrock83]

Firstly - you can't put unpublished GNSS approaches into IFR GPSs - they simply wont accept them. Its part of their certification.

So you are left with doing home brew approaches based off VFR GPSs or other navigation beacons.

A let down over the sea is still pretty safe. CFIT isn't a risk, so long as your altimeter is set. If you can get a traffic service from ATC, all the better.

Over land - your minimums are going to be pretty high for an unpublished approach. It doesn't take a rocket scientist to descend on a radial after crossing a VOR / beacon.

I wouldn't use GPS/ILS or some other app to go anywhere near the sorts of minimums I would on a published approach using a certified GPS. GPS altitude ambiguity and other issues (no alarms from a phone when it isn't getting an accurate GPS fix) mean it shouldn't be trusted, certainly for height info.

Some CAT operations have had their own approaches for years (I believe that there are unpublished GPS based approaches to places like Barra in use) but those are professionally created.

[terry holloway]

Firstly - you can't put unpublished GNSS approaches into IFR GPSs - they simply wont accept them. Its part of their certification.

So you are left with doing home brew approaches based off VFR GPSs or other navigation beacons.

A let down over the sea is still pretty safe. CFIT isn't a risk, so long as your altimeter is set. If you can get a traffic service from ATC, all the better.

Over land - your minimums are going to be pretty high for an unpublished approach. It doesn't take a rocket scientist to descend on a radial after crossing a VOR / beacon.

I wouldn't use GPS/ILS or some other app to go anywhere near the sorts of minimums I would on a published approach using a certified GPS. GPS altitude ambiguity and other issues (no alarms from a phone when it isn't getting an accurate GPS fix) mean it shouldn't be trusted, certainly for height info.

Some CAT operations have had their own approaches for years (I believe that there are unpublished GPS based approaches to places like Barra in use) but those are professionally created.
"A let down over the sea is still pretty safe"
Is "pretty safe" a positive or a negative statement? It's either safe or unsafe, and MSA is MSA whether you are over sea, land, or mountains which run down to the sea!!

[foxmoth]

It's either safe or unsafe

Totally disagree, lying in bed is generally thought to be safe, but if thats all you do you will suffer all sorts of problems - and it is where most people die!
Aerobatics by a trained but inexperienced aerobatic pilot is relatively safe at 3,000'+ but less safe at 2,000' and progressively less safe the nearer he gets to the ground and similar could said of many aspects in aviation!

[terry holloway]

Totally disagree, lying in bed is generally thought to be safe, but if thats all you do you will suffer all sorts of problems - and it is where most people die!
Aerobatics by a trained but inexperienced aerobatic pilot is relatively safe at 3,000'+ but less safe at 2,000' and progressively less safe the nearer he gets to the ground and similar could said of many aspects in aviation!
Therefore, using that logic it's safe to descend below MSA in IMC conditions! I disagree.
However, if one decides to do so, I agree it's less risky to descend over the sea, notwithstanding that there are less masts and aerials about than over the land, unless one encounters a ship! Risk management is an important element of safety, but safe/unsafe are viewed by most people as "black and white". Not grey!
As for staying in bed, that's not for me! Far too dangerous!!

[Jonzarno]

you can't put unpublished GNSS approaches into IFR GPSs - they simply wont accept them. Its part of their certification.

Actually, you can if you really really want to; it's fairly obvious how, but I wouldn't do so myself and don't intend saying how you can do so here. :uhoh:

[n5296s]

It's so obvious that surely anybody could work it out for themselves... just enter the sequence of waypoints. Of course you'll have to manage the altitudes yourself, and you won't get LPV or LNAV - just like a Mk I GPS approach.

The GPS approach to my own home airport (KPAO) always has to be manipulated along these lines, because ATC never, ever, ever uses the official IAFs. So you have to select one of them, then manually to "direct" to the IF they use. (If you care to look it up, the official IAFs are SAPID and LICKE, but you are almost always given directions to DOCAL, very occasionally vectored onto the ABSIW-PUDBY segment - even when my flight has taken me right through SAPID I've still been given "direct DOCAL").

[foxmoth]

Therefore, using that logic it's safe to descend below MSA in IMC conditions! I disagree.

That is not what I said at all - the point is that it is not safe or unsafe it has a level of safety, even staying above MSA cannot be said to be safe per se, if you are have an MSA of 2,000' and you go from 2,001' to 1,999' have you REALLY gone from safe to unsafe, what you can say is that, generally, remaining above MSA is going to be relatively safe, if you go higher than that you are safer and if you go lower you are less safe, and the further you get below MSA the more unsafe it becomes, but even that has variations, for example if you are sitting in a light single at 2,500' in icing conditions with an MSA of 2,400' and you get a pirep that the cloud base is 2,350' what is the safer option?

[Arfur Dent]

How low would you descend to over the sea??

[galaxy flyer]

N5396S,

Two different animals here, a non-TERPS'd home designed approach versus a usual ATC procedure to an operational advantage, that is, expedite traffic.

foxmoth,

While your example has some validity, air discipline requires as accurate as possible observance of established minima. If 1,999' is ok is 1,900'? When does one stop descending? All the errors in the error budget are not terrain, but instrument error, Venturi effects over mountainous terrain, ground reporting errors, etc.

GF

[The Ancient Geek]

1000 feet should be fairly safe, much below that you can find oil rigs and wind turbines.
But are you sure of your QNH ?

[foxmoth]

Galaxy,
My point was not if you should observe these limitations or not but the definition of safety, and that safety is not a black and white issue but a variable. Good airmanship dictates that you select the least risk option, generally that will mean you do not descend below MSA, but there can be situations where that may not be the safest option!

[n5296s]

Two different animals here
You're quite right, but my point is that as far as the GPS is concerned, an approach is just a sequence of waypoints. Whether those form part of a published approached, or whether they're user-defined ones that you made up as part of your home-brew approach, it neither knows nor cares.

I'm not recommending home-brew approaches, just saying that it isn't too hard to figure the mechanics of how to fly one.

[rotarywise]

How low would you descend to over the sea??Last time I did it, 125ft on the Rad Alt, but that was 50+ miles north of Iceland with no diversion. These days I would never descend below MSA without an approved IAP or radar vectors.

[27/09]

You're quite right, but my point is that as far as the GPS is concerned, an approach is just a sequence of waypoints. Whether those form part of a published approached, or whether they're user-defined ones that you made up as part of your home-brew approach, it neither knows nor cares.


Actually the GPS does know and care, very much.

With a published approach loaded the GPS will scale at the FAF from 1 mile to 0.3 mile full scale deflection and a TSO 146 GPS will scale to full scale deflection of 2 degrees inside the final fix down to 350 feet at the missed approach point.

A homebrew approach cobbled together using just a sequence of waypoints will be scaled to 1 mile at best and could be as much as 5 miles full scale.

I know what I'd want to use for an approach and it sure ain't some dodgy homebrew one.

[n5296s]

Actually the GPS does know and care, very much.

Good point, I'd forgotten about that (although of course it pops up on the GPS every time). It's another good argument against using a homebrew approach, as if any more were needed.

[bookworm]

A homebrew approach cobbled together using just a sequence of waypoints will be scaled to 1 mile at best and could be as much as 5 miles full scale.

It will be scaled to whatever you set it to. The more significant aspect is the integrity: the horizontal alerting limit may be significantly higher than for a procedure retrieved from the database

[compressor stall]

For those thinking of GPS and synthetic vision are infallible, have a read here.

https://www.caa.govt.nz/Accidents_and_Incidents/Accident_Reports/ZK-SML_Fatal.pdf

[n5296s]

I certainly don't think any of this stuff is infallible, but you can hardly lay this at the GPS. Yes, the terrain database was inaccurate, but presumably the aircraft had an altimeter. This is like truck drivers getting stuck under low bridges or people driving into rivers because they "followed the GPS".

[cessnapete]

Slightly off topic, but recently upgraded our G430 t0 430W. I have been amazed at the accuracy and stability of GPS approaches carried out. Even an LNAV/V with only advisory glideslope, (i.e. Shoreham) if flown accurately takes you to the Rwy numbers. Pity that unnecessary regulatory bulls..t prevents this great safety enhancing aid being stifled in CAA land.

[piperboy84]

Cessnapete
Slightly off topic, but recently upgraded our G430 t0 430W

I will be doing the same upgrade on my 430 later this year, what was the ballpark cost if you don't mind me asking?

[cessnapete]

Anything to do with aeroplanes, not cheap! C182Q
£2300 to Garmin UK to upgrade the internal hardware/software, quite a big mod apparently, new faster processor etc.
Then about another £2000 for avionics shop.
New GPS aerial and cable to G430 box.No new holes to cut as all new upgrade parts fit into present positions in aircraft. And nice new thick Garmin manual to teach you how to use it!
Includes a 'royalty' fee to GAMA Avionics for their time, expertise and paperwork for the mod in UK.
All done expeditiously and efficiently by RGV Glos.

[n5296s]

what was the ballpark costI just upgraded my 530 to a 530W, and replaced my 330 transponder with an ADS-B 345. Total cost including parts and labour was about $16K. Ouch.

I agree with pb84 - LPV approaches are a pleasure to fly.

[Council Van]

for example if you are sitting in a light single at 2,500' in icing conditions with an MSA of 2,400' and you get a pirep that the cloud base is 2,350' what is the safer option? Hopefully you would be sat in your arm chair at home having carefully studied the weather forecast and realised that the forecast conditions were not suitable for your aircraft/qualifications.

1000 feet should be fairly safe, much below that you can find oil rigs and wind turbines.
But are you sure of your QNH ?I flew maritime patrol for a living with a previous company. We would not decend below an absolute minimum of 1300ft on the forecast regional QNH if we had not become VMC as obstacles could be up to 299ft without being shown on a chart.

[foxmoth]

Hopefully you would be sat in your arm chair at home having carefully studied the weather forecast and realised that the forecast conditions were not suitable for your aircraft/qualifications.

Ideally yes, but if you have never been caught with an incorrect forecast you probably have not got too many hours under your belt, It is also very different operating commercially in light aircraft than someone who can choose to only fly in CAVOK conditions.

[Piltdown Man]

This thread is amazing! There are dead bodies and wreckage strew all over the place, well qualified professional pilots saying flying a DIY approach is a stupid thing to do and a bunch of plonkers saying it's OK. To those who think flying a home brewed approach is OK, may make one request please: Fill in a donor card. Your brain, although unused, will not be involved in any transplant.

PM

[alex90]

Fill in a donor card. Your brain, although unused, will not be involved in any transplant.


Shame they normally are beyond recovery by the time the ambulance gets to them...

This thread is making me feel as though there hasn't been enough lobbying to the UK CAA to allow GPS instrument approaches at uncontrolled airfields to be more widely accepted / cheaper (re: paperwork / CAA application fees).

Surely if the UK CAA had a duty of care, and had to ensure safety was paramount - all airfields in the UK would have GPS approaches.

[1800ed]

I've got a copy of a 'discrete procedure' for Wellesbourne - looks like it originates from 1995 and uses the HON VOR and DME. Is this the same as an unpublished approach? I've only ever used it during my IMCr training and I'm a bit unsure about what it is really!

[foxmoth]

My understanding is that this is a training procedure, only to be used in VMC, another interesting one is the VOR procedure at Goodwood - this USED to be a published procedure but got withdrawn, so how many would use that down to its (once) published minima?

[cessnapete]

Foxmoth
Flew the old GWC VOR/DME NPA and Hold on my last IR renewal. Worked a treat, and free!

[tmmorris]

My understanding is a discrete procedure is supposed to be for a specific company to use and approved only for them (with an AOC?). Not sure if the Wellesbourne VOR procedure is strictly one of those - like you I used it in training.

[Mark 1]

Putting aside the wisdom or otherwise of using non-published procedures, the legalities for a private operation seem to allow it (in the UK).

I.e. the minima for IFR in the ANO and SERA do not apply when taking off or landing without any mention of following a defined procedure.

So it would seem reasonable that a procedure established and maintained to the same standards as a published one should offer a similar level of safety. The arguments about separation from other traffic are not much different from those for operating IFR outside controlled airspace except that you are in the vicinity of an airfield and hence more likely to encounter other traffic.

So, I agree using a hastily home-brewed approach carries increased risk, but a well thought out one done to the prescribed standards should be legal and relatively safe.

[oggers]

ANO:

Operating minima

(3) For flights under Instrument Flight Rules, the pilot in command must select and use aerodrome operating minima for each departure, destination and destination alternate aerodrome which—

(a)must not be lower than those notified, prescribed or otherwise designated by the relevant competent authority

[bookworm]

ANO:…

Nice try. But ignoring for a moment the issue that the ANO is not applicable to the operation of EASA aircraft, the 1000 ft rule for IFR in SERA is not part of aerodrome operating minima.

There are dead bodies and wreckage strew all over the place,

I'm still waiting for some one to come up with a persuasive list of examples of the "dead bodies and wreckage" attributable to unpublished let-downs. Most of those the examples I've seen cited are accidents that did not seem to depend on whether or not an approach was published or approved.

[ShyTorque]

I know of accidents where pilots messed up published IMC let-downs and others where pilots attempted to let down without any sort of pre-planned procedure. However, I can only think of one accident where an "unpublished" let down resulted in an accident and that occurred because the procedure wasn't followed at all accurately. Paradoxically, and sadly, a CAA Ops inspector was on board and perished along with the crew.

The same organisation suffered another, more recent and well publicised accident during an attempted IMC departure by a relatively inexperienced crew.

[oggers]

Nice try. But ignoring for a moment the issue that the ANO is not applicable to the operation of EASA aircraf

Bookworm, I was replying to this:

I.e. the minima for IFR in the ANO and SERA do not apply when taking off or landing without any mention of following a defined procedure.

It's a thread, if you can follow it.

[Sir Niall Dementia]

Shy;

Is this the one you're refering to? http://www.aaiu.ie/node/11 The late great Spotty Muldoon was the examiner on board.

Another, more recent one: https://www.gov.uk/aaib-reports/aaib-investigation-to-sikorsky-s-76c-g-wiwi I think we both knew the crew from that, and we both definately knew this guy:https://www.gov.uk/aaib-reports/agusta-a109a-ii-n2nr-23-october-2010

SND

[tmmorris]

Hmm. All rotary.

[bookworm]

I know of accidents where pilots messed up published IMC let-downs and others where pilots attempted to let down without any sort of pre-planned procedure. However, I can only think of one accident where an "unpublished" let down resulted in an accident and that occurred because the procedure wasn't followed at all accurately. Paradoxically, and sadly, a CAA Ops inspector was on board and perished along with the crew.

Indeed if you are referring to G-HAUG, the primary cause was the deviation from the planned procedure. In the conclusions:

3.1.20 No evidence was found that would indicate that the aircraft would have experienced any difficulty in following the selected route, MOIRA - WARRN - MAP - B, if the aircraft had been operated throughout in the fully coupled mode, with Nav Capture, and allowed to fly the selected route without manual intervention.

There is an argument that a PANS-OPS compliant procedure would have offered more margin for error. But in general, deviating more than 1.3 miles from an RNP 0.3 final approach segment of a published procedure is also bad news.

[oggers]

Would some one who is flying an unpublished approach in IMC below the safety altitude please inform the CAA with all the details if they feel it is legal and then let's see if they are prosecuted or not.

Hear hear. After all:

NCO.OP.110 Aerodrome operating minima — aeroplanes and helicopters

(a) For instrument flight rules (IFR) flights, the pilot-in-command shall select and use aerodrome operating minima for
each departure, destination and alternate aerodrome. Such minima shall:

(1) not be lower than those established by the State in which the aerodrome is located, except when specifically
approved by that State; and

(2) when undertaking low visibility operations, be approved by the competent authority in accordance with Annex V
(Part-SPA), Subpart E to Regulation (EU) No 965/2012.

So whether you operate iaw the ANO or Part-NCO, you may only descend below your minumum safe altitude in IMC if you are following an approved procedure.

[bookworm]

Your logic eludes me. Did you highlight the bit on "low visibility operations" for a reason? Where do you get "minimum safe altitude" from?

[oggers]

Your logic eludes me

Clearly.

Where do you get "minimum safe altitude" from?


According to Skybrary, "Minimum Safe Altitude is a generic expression, used in various cases to denote an altitude below which it is unsafe to fly owing to presence of terrain or obstacles. An ICAO definition of the term "minimum safe altitude" as such does not exist." It is just a piece of jargon that a lot of seasoned pros would understand, like 'platform altitude' or any number of other phrases. Sorry it threw you.

[ShyTorque]

Oggers,

I think you are reading more into that than is actually intended. It is about operating minima, as it says.

Your quote does not include any reference to descent below MSA or approved procedures.

[oggers]

Shy, have a read of this:

Aerodrome operating minima (AOM) for IFR flights are set out in some detail. They are “selected and used” by the pilot-in-command. They cannot be lower than those established by the state in which the aerodrome is located, and cannot include low visibility operations (550 m RVR for approach, 400 m RVR for take-off) without a specific approval. Note that the 400 m RVR for take-off is higher than the 150 m required under the UK ANO.

AOM are in two parts:

Decision heights and minimum descent heights are specified in the implementing rules, and are calculated on the same basis as under most national rules and EU-OPS. The DH/MDH is usually the higher of the OCH or the system minimum for the approach aid.

Minimum RVRs and visibilities are set out in guidance material. In principle, the pilot is at liberty to select these within the constraints mentioned above. In practice, I suspect most will use those in the Guidance Material or published by Jeppesen, which are substantially the same as for CAT.

The author participated in the Part-NCO review group in 2010, working with EASA and other stakeholders on the text of Part-NCO.


It is pretty clear to me that whatever discretion private operators had to exploit homebrew approaches back in the day no longer exists.

[bookworm]

ROTFLMAO. :)

[ShyTorque]

Oggers, it refers to the bit at the end of an approach, no reference to MSA.

[oggers]

ShyTorque

Oggers, it refers to the bit at the end of an approach, no reference to MSA.

Yes the approach. That is what gets you down from safety altitude to minimums. I have shown you the regs. You are interpreting them differently from me, so here is some further guidance from the CAA:

User-defined approaches can be dangerous and are not authorised. [Safety Sense Leaflet #25]

For operations in IMC, below safety altitude the use of user waypoints, and modification of the published procedure using temporary waypoints or fixes not provided in the database, is potentially hazardous and should never be attempted. The manual entry of coordinates into the RNAV system by the flight crew is not permitted for RNAV operations within the terminal area and should never be done below safe altitude in any location. [CAP 773 Flying RNAV (GNSS) Non-Precision Approaches in Private and General Aviation Aircraft]

It is in the ANO, it is in Part-NCO, it is spelled out in CAP773. You cannot descend below safety altitude in IMC unless you are using an approved procedure.
.

[A le Ron]

ShyTorque



Yes the approach. That is what gets you down from safety altitude to minimums. I have shown you the regs. You are interpreting them differently from me, so here is some further guidance from the CAA:

User-defined approaches can be dangerous and are not authorised. [Safety Sense Leaflet #25]

For operations in IMC, below safety altitude the use of user waypoints, and modification of the published procedure using temporary waypoints or fixes not provided in the database, is potentially hazardous and should never be attempted. The manual entry of coordinates into the RNAV system by the flight crew is not permitted for RNAV operations within the terminal area and should never be done below safe altitude in any location. [CAP 773 Flying RNAV (GNSS) Non-Precision Approaches in Private and General Aviation Aircraft]

It is in the ANO, it is in Part-NCO, it is spelled out in CAP773. You cannot descend below safety altitude in IMC unless you are using an approved procedure.
.

No matter how much you wish to kill yourself.

[oggers]

^^^^^^^^^^^^^^^^:ok:

[bookworm]

All right. I've recovered my composure enough to type again… :)

Aerodrome operating minima are established for aerodromes for take-off and landing. They consist of a decision height or minimum descent height and an associated visibility condition for each approach. Aerodrome operating minima may be published by the state, although these days the UK simply adopts what it says in the corresponding part of the EASA Air Ops Regulation, in this case Part-NCO.

The rule that you want to apply as "MSA" is in Part-SERA.

SERA.5015 Instrument flight rules (IFR) — Rules applicable to all IFR flights
(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 (1), 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.

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. Almost all CAT operations manuals will require that if relatively conservative minima for a visual approach are not met. But there is no requirement that a published procedure is used to meet the requirements of SERA.5015(b) when operating under Part-NCO.

[Sillert,V.I.]

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.

[oggers]

Bookworm

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.

That is not something that anybody has taken issue with. Nonetheless the rules on aerodrome operating minima do also exist.

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.

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.

But there is no requirement that a published procedure is used to meet the requirements of SERA.5015(b) when operating under Part-NCO.

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.

[bookworm]

But the regulations say you have to obey the aerodrome operating minima which in turn has to be approved by the state.

No, they don't say that the aerodrome operating minima have to be approved by the state. Approval is only required if you wish to conduct Low Visibility Operations (landing with an RVR less than 550 m). If the state has notified AOM for a particular approach, you cannot choose lower AOM. If the state has not, you may select your own AOM. States generally do not notify AOM for other than runways with instrument approach procedures.

Equally, 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.

[then arrive at minimums without the required visual references and still legally continue, merely because it was 'for the purpose of landing'.

No, that aspect is not permitted by NCO.OP.210(e):

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.

[tmmorris]

I'm sure it does, but your company's ops manual isn't the law.

I don't think Bookworm is claiming people should do it, just that there is no legal obstacle to doing so.

[ShyTorque]

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.

No matter how much you wish to kill yourself.
I have absolutely no intention of killing myself, or anyone else. But thanks for your advice anyway.

[BEagle]

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:

4.12 Aerodromes Without Published Instrument Approach Procedures

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.

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' :rolleyes:

[ShyTorque]

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.

[BEagle]

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.

[Pace]

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 ??

[Romeo Tango]

IMHO when things like aeroglass (https://glass.aero/) have a few years experience and debugging this discussion will become moot.

[ShyTorque]

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.
Beagle, I was taught never to use abbreviations in written text unless they were explained in full at first instance. I'd be grateful if you could do so with regard to your post, thanks.

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-investigation-to-sikorsky-s-76c-g-wiwi

[Good Business Sense]

AMC/GM

Some unknown persons opinion of what he/she would like the law to mean (because the laws are so well written :ugh: )

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.

[150 Driver]

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.

[ShyTorque]

Beagle, While 'Shall' denotes a mandatory requirement, the word 'should' expresses a recommendation or advice.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. :)

[oggers]

ShyTorque

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.

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.

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

In your opinion. But in the CAA's opinion:

User-defined approaches can be dangerous and are not authorised

[oggers]

Bookworm, I wrote:

by your logic, it would be legal to descend from safety altitude on some half baked procedure, then pick up a published approach


You wrote:

So far so good -- that's not significantly different from vectoring.


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).

[ShyTorque]

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.

[ShyTorque]

Oggers,
The problem is you believe that it is still legal for GA pilots to carry out unapproved let downs below safety altitude.

Here is the relevant "present" rule (copied direct from the CAA website which links to a .PDF):

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.

[chevvron]

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.

[bookworm]

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).

Yes, if you meant shortcutting a segment of a procedure with obstacles less than 1000 ft below, I can't see much reason to do that. But I don't really see the relevance. You wrote:

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'.

It would not be legal to continue, however you got on to the procedure. NCO.OP.210(e) forbids it.

[Pace]

The CAA or any regulatory body will regulate to cover their own backs as well as the obvious safety angle.
I have been flying for 35 years nowadays totally CAS but going back knew many airfields where unpublished procedures were used by even professional pilots usually with a lot of local knowledge and usually on an NDM or other aid with a GPS overlay

A bad pilot can mess up and crash on a published procedure the published part doesn't mean an unpublished procedure isnt cannot itself be a good procedure only that it is not published i.e approved

I am not at all promoting the use of un published procedures but stating the fact that throughout that course of 35 years I know of many even used by professional pilots

OCAS it was probably considered as "creative flying" for those who must fly rather than choose to

[ShyTorque]

Chev, I've often wondered how accurate ATC radars are when compared to modern, IFR certified on-board GPS equipment.

Almost every time I ask for a radar service I'm given a reason why it's only a limited service.

[oggers]

Bookworm:

It would not be legal to continue, however you got on to the procedure. NCO.OP.210(e) forbids it.

...which is why your cherry picking of the rule permitting 'descent in IMC below safety altitude for the purpose of landing' without the need to be established on an approved procedure is such patent cobblers. If it were permitted to carry out home-made approaches there would be no reason that you could not start out on an approved procedure and at some point lower down decide 'I'm going to work to my own made-up minima from here on, and it will be legal because I intend to land'. :ugh:

ShyTorque

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.

Well, we are actually discussing what is legal for GA not public transport, and that recommendation pre-dates the publication of both the latest ANO and Part-NCO by 2 years. Anyway, here is the CAA guidance you remain in denial of:

User-defined approaches can be dangerous and are not authorised

[ShyTorque]

I'm not in denial of anything. I'm pointing out the difference between official guidance (which I don't disagree with in any way) and the legal position.

It appears that some don't understand that there is a difference.

The CAA website I quoted from has been placed by the authority itself to highlight national differences from the regulations under SERA. With regard to the subject under discussion, they have not elected to differentiate or change what the regulations state. The website was placed to inform all interested parties and is updated more regularly than the ANO.

The rules for public transport are obviously more strict than those for private operations, for very good reason. Part-NCO is a way of further regulating private operations. But not all operations will be covered by those new regulations, based on aircraft maximum weight.

[chevvron]

Chev, I've often wondered how accurate ATC radars are when compared to modern, IFR certified on-board GPS equipment.

Almost every time I ask for a radar service I'm given a reason why it's only a limited service.
For some reason, many controllers seem to cover their backs nowadays by saying 'poor radar performance' or something similar. This only refers to low coverage, not to overall accuracy which is regularly (at least in the UK) checked.
I once watched a certain rock star attempt to fly his own approach into Blackbushe in his newly purchased Navajo (normally flys a Harvard - gives the game away doesn't it!) . We could see he was on final for Lasham not Blackbushe, but no amount of us telling him would convince him until he broke cloud and could see we were right.

[ChickenHouse]

Could somebody please define the difference between "unpublished or 'home-grown' instrument let-downs" and "flying low"?

If there is no published procedure to land, there is no procedure to land. If I am performing a flight in IMC under IFR to fly low to check whether I am able to land VMC at an uncontrolled airfield, when does "let-down" begin? At a specific height, or a distance to the field, or? The pilots intention is not (yet) a measurable quantity.

[27/09]

I shake my head at some of the stuff on this thread.

How many posters actually hold an instrument rating?

Chickenhouse, to me "Flying Low" infers you are VMC below the cloudbase in sight of the ground but in order to stay VMC you need to fly lower than the legal minimum above ground level altitude.

For me (unless you're in controlled airspace) the let down starts the minute (assuming you are still IMC) you descend below the MSA (Minimum Safe Altitude) for the Airway you're on and/or when you leave the Airway to track across no mans land (in other words you no longer have a promulgated MSA, unless you have radar coverage) towards the destination airfield.

Flying away from published tracks (random routing) outside of controlled airspace is strictly forbidden here below FL150

[Pace]

27/09

You are on a flight from say Gloucester to Caernarfon cloud base 1500 feet. You are IMCR rated and comfortable flying in clouds
How would you have completed that flight ?
I am not promoting un published or home made approaches just stating a fact that in 35 years of flying pilots flying OCAS regularly used such procedures

The most dangerous flying is attempting to fly vmc in lowering cloud and visibility around high ground or commonly known as scud running
A controlled procedure is better than no procedure

[BEagle]

Assuming Class G UK airspace, pilot has an instrument qualification and is flying an aeroplane:

1. If completely certain of position, descend as you wish to no lower than 1000ft above the highest obstacle within 5nm.
2. Further descent may only be under a published Instrument Approach Procedure or in accordance with VFR.
3. If you do not have sight of the surface below 3000ft amsl (or 1000ft above terrain, whichever the higher), you do not meet VMC criteria (thanks to nanny-SERA) and should follow the UK IAIP guidance - divert to somewhere which is VMC or has a published IAP.
4. If you do have sight of the surface, remain clear of cloud and fly at 140KIAS or less, you are in VMC provided that the visibility is no less than 1500m.

So, putting all this together, I would see no problem with a pilot flying to an 'initial point' on the extended centreline of the RW, which is 1000ft above the highest obstacle within 5nm, then if in sight of the surface, clear of cloud and below 140 KIAS, flying a descent to the aerodrome with navigational guidance but under VFR. Thus a 'degraded visual environment' approach, not an 'unpublished instrument approach'.

[foxmoth]

27/09 - most of what you say is not applicable to this thread as your rules seem totally different to the UK which is where most of this discussion is talking about, IFR outside CAS is not only permitted but frequently flown.

[foxmoth]

For Paces flight I would fly to Caernarfon at an appropriate IFR level then let down out to sea down to a 1,000' minima, preferably talking to Valley for both traffic, met reports and confirmation of position, if I could not get visual then I should be able to get an approach to Valley.

[Pace]

Foxmouth

Exactly you would probably cross the NDB confirmed with GPS and ATC and let down in a teardrop a so called un published but safe approach

[foxmoth]

Strictly speaking it is a cloudbreak rather than an unpublished approach!

[2 sheds]

Strictly speaking...define "cloudbreak"!

2 s

[foxmoth]

Descent to MSA to get below cloud not neccesarily to a runway, an "approach" is normally to a runway, so in Paces example you could be in or above cloud at say 6,000' and descend en route to do a cloud break at the en route MSA of say 4,300' (not looked up the actual MSA here) but with a cloudbase of 1500' the only realistic cloudbreak is going to be out over the sea - and I would want to be below cloud before I was back within 5nm of the coast.

[2 sheds]

I was just making the point that terms such as cloudbreak and unofficial letdown are bandied about when they are not defined and may therefore imply different things to different people. What you are advocating is compliance with the Rules of the Air!

2 s

[foxmoth]

What you are advocating is compliance with the Rules of the Air!

2 sI never said otherwise!

Actually There are cloudbreak procedures officially promulgated, iirc one of the Cuban airfields has one

[ShyTorque]

2. Further descent may only be under a published Instrument Approach Procedure or in accordance with VFR.

Beagle, please post your reference for that statement.

[BEagle]

part-NCO spells out that aerodromes are subject to national limits.
UK IAIP makes clear the UK policy on aerodromes without IAPs.

By the way, do you fly on an EASA licence? If so, you should be well aware of the meaning of AMC/GM and AltMoCs...

[27/09]

Pace: You are on a flight from say Gloucester to Caernarfon cloud base 1500 feet. You are IMCR rated and comfortable flying in clouds
How would you have completed that flight ?
I am not promoting un published or home made approaches just stating a fact that in 35 years of flying pilots flying OCAS regularly used such procedures

The most dangerous flying is attempting to fly vmc in lowering cloud and visibility around high ground or commonly known as scud running
A controlled procedure is better than no procedure

Pace I have NFI where those two places are nor the surrounding terrain. I don't have any charts of the area

However I assume there is an Airway linking those two places, I'd descend to the MSA for that route and if not visual proceed to the closest suitable airfield with a promulgated IAP and land there.

foxmoth: 27/09 - most of what you say is not applicable to this thread as your rules seem totally different to the UK which is where most of this discussion is talking about, IFR outside CAS is not only permitted but frequently flown.

Our rules may be different, but descent below a minimum flight altitude in IMC while not on a published procedure doesn't make any sense no matter which rules you operate under.

By the way there is a significant amount of IFR flying conducted outside of CAS in this part of the word. I'd guess at least some part of about 70 - 80 % of my IFR flights has been outside of CAS.

[ShyTorque]

part-NCO spells out that aerodromes are subject to national limits.
UK IAIP makes clear the UK policy on aerodromes without IAPs.

By the way, do you fly on an EASA licence? If so, you should be well aware of the meaning of AMC/GM and AltMoCs...
Beagle, Again, but without the stalling tactics, I'd be grateful if you would expand both the abbreviations and provide a reference in your other post to back up what you wrote. Part-NCO doesn't apply to my operations. Thanks.

[Good Business Sense]

ShyTorque,

Don't worry you are right. Many people are producing statements taken out of context.

The Safety Sense 25 document was a lot of tosh when it was badly written in 2009 and eight years later it reads even worse. Even in 2009 there were more LPV approaches in the USA than ILSs - many, many of them without an ATC facility.

In 2009 I talked to the chap in the CAA who was in charge of GPS rollout, who I believe wrote the aforementioned document, and I was told that the use of GPS and GPS approaches was still all a bit too dodgy/risky and it was not a mature technology. Thankfully, he had the good grace to wind his neck in when I mentioned that his comments were a concern as my airline, one of the largest in the world, had been doing them in widebodies every day for many years.

The introduction of WASS in the states... many years ago ...... brought the accuracy of GPS down from 10-15 metres to around one metre. The equipment available at reasonable cost, with all the protections, even for the smallest, lightest aircraft, is incredible - knowing your position down to 10 metres or so is unbelievable. Goodness, synthetic vision has now been introduced to GA and TAWS as well as TCAS are also available as add ons.

You can get a GPS approach done for you very cheaply by many companies advertising on the net.... you can get the software and be trained to do it yourself.

China is building over 200 airports before 2020 and none of them will have a VOR, NDB or ILS !

... and here in the UK we are still screaming, "here be dragons"

If you are a reasonably experienced instrument rated pilot you should be able to plan a sensible, safe, non airport located, cloud break with a device that tells you your position to within 10 metres and the basic IFR law allows for this. Many aviation companies/entities need to do this every day whilst carrying out their tasks and they have developed good SOPs to keep it safe and LEGAL.

[foxmoth]

By the way there is a significant amount of IFR flying conducted outside of CAS in this part of the word. I'd guess at least some part of about 70 - 80 % of my IFR flights has been outside of CAS.

??? In one place you say
Flying away from published tracks (random routing) outside of controlled airspace is strictly forbidden here below FL150 - which to me is CAS or much the same, then you say you fly outside CAS, which is it???
In Paces example there is no airway and no CAS, in the UK we can fly IFR on any routing we choose if outside CAS.

[27/09]

Foxmoth,

Do you have an Instrument Rating?

Airways and Controlled Airspace are two different things. I don't have access to your UK charts, But looking on Skyvector it would seem to me you guys have Airways that proceed outside of controlled airspace, just like we do here.

I fail to see what you're getting at when you say Airways and CAS as being the same thing. They're not.

One area where we do differ is random routing outside of controlled airspace. This is absolutely forbidden here below FL150. How do you guarantee you are safely clear of any terrain, and unless using GPS how can you easily pin point your position to even know where you are?

Flying around in cloud like you guys do on a random track outside of controlled airspace makes the hair on the back of my neck stand up.

[Sir Niall Dementia]

27/09;

Here in EASA land airways are controlled airspace. IFR outside CAS is perfectly permissible. For her he route described earlier, there is an airway well above and a plenty of CAS for Bristol and Cardiff which puts the base way up.

I fly rotary mainly and fixed wing when ops let me and an awful lot of my Public Transport rotary flying is IFR outside CAS. It's the way it is and it works.

SND

[foxmoth]

How do you guarantee you are safely clear of any terrain, and unless using GPS how can you easily pin point your position to even know where you are?

Yes I have an IR, and on it, besides GPS I learnt how to use a VOR, DME and even ADF, didn't you?? ( in fact I even learnt Decca, but never used that apart from in the RN),add in radar assistance and it is not that hard to know where you are, Sir N has answered the other points.
As a matter of interest, how does an airway work if not CAS, it seems to me you are then just forcing all the aircraft into the same airspace, and if not controlled you are actually increasing the collision risk!

[piperboy84]

Flying around in cloud like you guys do on a random track outside of controlled airspace makes the hair on the back of my head stand up.

I've heard it said that in the U.K. there has not been a midair collision in uncontrolled airspace in IMC conditions since WW2. Not sure about down south were it's busier but up in Scotland where I fly IMC in Class G with a basic service (non radar but similar to VFR flight following in the US) the chances of bumping into something man made is zilch. Icing and granite is another story if you don't do your homework or read the charts

[27/09]

Foxmoth, Yep I have VOR, ADF , GPS on my IR. They're all quite easy to use.

An Airway doesn't need to be in CAS, at least not in this part of the world. The Airway has a minimum altitude assigned to it, this may change at various DME points along it's route to ensure clearance from terrain.

While we usually follow Airways inside CAS, since CAS usually also means surveillance airspace we often get direct (random route) tracking.

In this part of the world we could not operate outside of controlled airspace without Airways. There's far to much cumulo granite about.

There's never been an issue with traffic conflicts on an Airway outside of CAS.

A, the traffic on these routes is never that great to start with, B all IFR flights are on a Flight Plan and IFR flights are advised of other IFR flights and where necessary each flight co-ordinates with other flights to ensure separation.

While the perceived risk of collision with another aircraft may be higher the very real risk of collision with cumulo granite all but disappears.

How do you go point to point outside of CAS and no Airway. Are you flying from nav aid to nav aid? If not how do you quickly and accurately pin point your position? Is the nav aid coverage that good every where in the UK? How do you ensure safe terrain clearance?

You mention radar assistance, that to me infers you are in controlled airspace, is that so? There is no radar assistance outside of CAS here.

Due to the topography there's large parts of NZ that don't have radar coverage so no chance of radar assistance.

[Flyingmac]

If you are a reasonably experienced instrument rated pilot you should be able to plan a sensible, safe, non airport located, cloud break with a device that tells you your position to within 10 metres .


:D:ok: In my case it's two metres.:) First choice is the GPS.

[foxmoth]

27/09, your posts makes my point that you are talking a very different set of rules, here I can launch off IFR without a flight plan, outside CAS there is often radar assistance from various providers, they may not give you radar CONTROL, but they will give traffic info and confirm your position, whilst we do not have the terrain problems you have in NZ (highest ground here is about 3,600') I would have thought even there you should know what your position is near enough to be able to know what your MSA is, heck, I could do THAT with just DR nav!!
I think one reason Pace picked the route he did is because there is no CAS, including airways, below 10,000' and it goes over high ground including very close to mount Snowdon which is the highest terrain in the UK! Edited to add - highest in the UK outside of Scotland!

[Flyingmac]

As a Scot, I couldn't let tat one go.


The highest point in Scotland (also the highest in the United Kingdom) is Ben Nevis (https://en.wikipedia.org/wiki/Ben_Nevis), standing at 1344 metres (4409 ft.).

[foxmoth]

Apologies FM, you are of course correct!

[mm_flynn]

Just had a quick look at NZ rules and airspace classifications, which are of course very different to the UK.

NZ
Controlled airspace A, C, D. Appears organised like the US for Class C and D. Class A is the same as UK airways, but appears to only be high level for commercial jet traffic.

There are 'Airways' in class G that are defined routes that guarantee terrain clearance. It is mandatory to be receiving traffic information if operating under IFR, but appears to rely on self separation for collision avoidance.

UK
Airways are almost always class A and can be quite low level.
Class C is used like the the US Class A to ensure all aircraft are under positive control at 'jet' levels.
Class G, there is absolutely no requirement to talk to anyone or receive any service IFR or VFR, VMC or IMC.
There are no (or almost no) Class G advisory routes, and the Class F routes are in very remote areas. So effectively, 'all' airways are controlled.
most GA IFR flights are on random routes where altitudes for sufficient terrain clearance are established by the pilot during flight planning.

[2 sheds]

There are 'Airways' in class G that are defined routes that guarantee terrain clearance. It is mandatory to be receiving traffic information if operating under IFR, but appears to rely on self separation for collision avoidance.
So they are not, by definition, airways. Even to put the word in quotes is completely misleading.

2 s

[ShyTorque]

If I remember correctly, in UK there used to be something similar called "Advisory routes".

But they couldn't be defined as Airways there.

[27/09]

2 sheds: So they are not, by definition, airways. Even to put the word in quotes is completely misleading.

2 Sheds would you like to give is your definition of an Airway.

I can assure you they are Airways that mm_flynn is referring to.

[foxmoth]

An airway is: a control area or portion thereof established in the form of a corridor. (ICAO Annex 11)

And Control area A control area (CTA) is an aviation term that describes a volume of controlled airspace

And to really tie it down
Controlled Airspace is defined as airspace of defined dimensions within which air traffic control service is provided to IFR flights and to VFR flights in accordance with the airspace classification.

So by ICAO definition, what you describe are not Airways, here they might be called Advisory routes, though I suppose a better name for yours would be "Compulsory Instrument Routings"

[piperboy84]

And Control area

So by ICAO definition, what you describe are not Airways, here they might be called Advisory routes, though I suppose a better definition for you would be "Compulsory Instrument Routings"

Interesting, I get the airway/corridor bit, but I always that a Control Area was airspace around a Control Zone that did not go all the way to the deck, like the second tier on a upside wedding cake.

[foxmoth]

Well I suppose they are just really extensions of the wedding cake layer joining up different cakes!:8

[tmmorris]

Stop it, you're making me hungry...

I think pilots in the US forget that all of the US is controlled airspace by ICAO definition - class E everywhere from 700/1200ft AGL. So any airway will be in CAS and require a clearance to fly IFR. Whereas the U.K. Is mostly class G.

[27/09]

And then there's this definition.

An airway is a legally defined corridor that connects one specified location to another at a specified altitude, along which an aircraft that meets the requirements of the airway may be flown. Airways are defined with segments within a specific altitude block, corridor width, and between fixed geographic coordinates for satellite navigation systems, or between ground-based radio transmitter navigational aids (navaids) (such as VORs or NDBs) or the intersection of specific radials of two navaids.

No mention of CAS.

I also found this bit of info as well. In most land areas of the world, aircraft are required to fly airways between the departure and destination airports

Foxmoth. I think our Airways are more aligned to the FAA system with very little in common with the UK Airways. We shall have to agree to disagree. Plus we are getting away from the original discussion of un published let downs.

[foxmoth]

Where is your definition from? I would have thought the ICAO one is the international authority. Certainly the second quote seems more a wikipedia style quote as I have flown in many areas of the world and there are very few that I know where you are REQUIRED to fly airways between airports - from what you have said before even in NZ not a requirement if VFR.
Agree though, major thread drift here.

[BEagle]

SERA definition:

36. ‘airway’ means a control area or portion thereof established in the form of a corridor;

[mm_flynn]

The point of my posting was to highlight that in NZ it appears the term 'airway' is used differently than in Europe (or the ICAO definition).

If you look at H249 near TIMARU VOR, it is charted for all the world the same as an IFR airway (on Skyvector), but is clearly in class G, and is provided with an ATService, but not ATControl (possibly logically similar to the way the UK provides procedural control in uncontrolled airspace).

The difference clarifies 27/09's comment about always on airways but mostly uncontrolled.

In NZ, there appear to be very few airports without an approach that have surrounding terrain that would be suitable for non-Darwin Award winners to undertake a DIY approach.

[2 sheds]

in NZ it appears the term 'airway' is used differently
Unless you can quote from the NZ AIP, I doubt that. Are you sure that it is not just quoted as an ATS Route? Either way, the AIP will specify the class of airspace for that route.


2 s

[oggers]

Good Business Sense

The Safety Sense 25 document was a lot of tosh when it was badly written in 2009 and eight years later it reads even worse. Even in 2009 there were more LPV approaches in the USA than ILSs - many, many of them without an ATC facility.

Badly written according to you but not according to the CAA, EASA or any official source. Part-NCO and the ANO are current as of now and say operating minimums cannot be less than those approved by the state. It is irrelevant how many LPV approaches there were in the USA in 2009 because they were all approved by the FAA whereas this thread is "Unpublished let-downs".

In 2009 I talked to the chap in the CAA who was in charge of GPS rollout, who I believe wrote the aforementioned document, and I was told that the use of GPS and GPS approaches was still all a bit too dodgy/risky and it was not a mature technology. Thankfully, he had the good grace to wind his neck in when I mentioned that his comments were a concern as my airline, one of the largest in the world, had been doing them in widebodies every day for many years.

You will of course be able to name the airline and reproduce the unapproved GPS approaches that you were carrying out every day to below safety altitude in IMC

The introduction of WASS in the states... many years ago ...... brought the accuracy of GPS down from 10-15 metres to around one metre. The equipment available at reasonable cost, with all the protections, even for the smallest, lightest aircraft, is incredible - knowing your position down to 10 metres or so is unbelievable.

Again, no argument that WAAS is a huge step forward. But it doesn't matter if it is 10 meters or 10cm accuracy, it still needs to be an approved procedure if you are going to descend below safety altitude in IMC.

... and here in the UK we are still screaming, "here be dragons"

Nobody is suggesting that GPS approaches are less safe than ground based approach aids. The argument is about home-made approaches. It is the job of the regulator to check that approaches are designed to the requisite standard. The CAA lag way behind the FAA in facilitating the approval of RNAV approaches, there is no argument about that.

if you are a reasonably experienced instrument rated pilot you should be able to plan a sensible, safe, non airport located, cloud break with a device that tells you your position to within 10 metres and the basic IFR law allows for this.

Only down to safety altitude unless you are using an approved procedure.

Pace:

Exactly you would probably cross the NDB confirmed with GPS and ATC and let down in a teardrop a so called un published but safe approach

It isn't much of an approach unless it gets you down below safety altitude, and it cannot do that legally unless it has been approved.

ANO Operating minima:

(3) For flights under Instrument Flight Rules, the pilot in command must select and use aerodrome operating minima for each departure, destination and destination alternate aerodrome which—

(a)must not be lower than those notified, prescribed or otherwise designated by the relevant competent authority

Part-NCO NCO.OP.110 Aerodrome operating minima — aeroplanes and helicopters:

(a) For instrument flight rules (IFR) flights, the pilot-in-command shall select and use aerodrome operating minima for each departure, destination and alternate aerodrome. Such minima shall:

(1) not be lower than those established by the State in which the aerodrome is located, except when specifically approved by that State

ICAO Annex 6 2.2.2.2 Aerodrome operating minima:

The pilot-in-command shall not operate to or from an aerodrome using operating minima lower than those which may be established for that aerodrome by the State in which it is located, except with the specific approval of that State.

[Good Business Sense]

Oggers,

I'm afraid I found your responses above incongruous. However, .....

Do you fly in Class G or is it always on airways high level in something heavy?

You present information/regulation relating to "aerodromes" to make your case - there is a whole world out there that doesn't fly to/from departure, destination and alternate aerodromes - your take on the LAW is out.

Enjoy the higher levels

[Jonzarno]

I don't think it is a simple distinction between flight in airways vs flight OCAS. For example, see this accident (https://aviation-safety.net/database/record.php?id=20120301-0) in which a Citation cancelled IFR to do a home made approach into an airport with no instrument approach.

The pilot had probably done this many times before and, for all I know, perhaps into other similar airports. For whatever reason, this time it went wrong.

[Good Business Sense]

Hi Jonzarno,

Two different subject matters i.e. The LAW and good airmanship etc.

...... without mixing up/pulling in references to aerodromes, etc etc see SERA 5015.

Cheers

I don't think it is a simple distinction between flight in airways vs flight OCAS. For example, see this accident (https://aviation-safety.net/database/record.php?id=20120301-0) in which a Citation cancelled IFR to do a home made approach into an airport with no instrument approach.

The pilot had probably done this many times before and, for all I know, perhaps into other similar airports. For whatever reason, this time it went wrong.

[Jonzarno]

I was thinking more in terms of the Laws of Physics......

[n5296s]

I think pilots in the US forget that all of the US is controlled airspace by ICAO definition - class E everywhere from 700/1200ft AGL. So any airway will be in CAS and require a clearance to fly IFR. Whereas the U.K. Is mostly class G.
Not quite all true. "Normally" Class E starts at 14000 feet (in the same way that "conventional" aeroplanes are taildraggers). It's true that in populated places it starts at 1200, sometimes down to 700 and even sometimes down to the ground. But in unpopulated areas it's all over the place. Take a look e.g. at the area around Las Vegas, where there are incomprehensible little corridors at odd altitudes.

In any case in the US, even to fly IFR in Class G (which most US pilots have never heard of and don't believe is possible) you still need to be on an IFR flight plan.

[ShyTorque]

I was thinking more in terms of the Laws of Physics......
Please explain what you mean by that.

There are obviously some here who still don't properly understand SERA 5015 (and its equivalent in the UK ANO in previous times). The "Safety Sense" leaflet, although giving advice, is not the legal definition. Check the wording of both.

I note that Beagle has gone totally quiet on this matter and has been obviously reading SERA since he has found a quote regarding the definition of an airway. Hopefully he now understands the wording properly!

[bookworm]

Several pages ago I wrote:
I'm still waiting for some one to come up with a persuasive list of examples of the "dead bodies and wreckage" attributable to unpublished let-downs. Most of those the examples I've seen cited are accidents that did not seem to depend on whether or not an approach was published or approved.

and so now we see this example (interim report here (http://www.bfu-web.de/EN/Publications/Interim_Reports/IR2012/I1_Report_12_CX005_C750_Egelsbach.pdf?__blob=publicationFile )) quoted:

For example, see this accident in which a Citation cancelled IFR to do a home made approach into an airport with no instrument approach.
The pilot had probably done this many times before and, for all I know, perhaps into other similar airports. For whatever reason, this time it went wrong.

When you describe it as a "home made approach" then I suppose you're correct, in the sense that all VFR approaches are to some extent "home made". The ATIS available at EDDF gave 8000 FEW004. The report for EDFE (which was not available to the crew) gave 4000 FEW008. No evidence is presented in the report that suggests that the crew flew any sort of unpublished let-down which got them into trouble. Rather, they attempted to fly night VFR and got caught out, while making an unstabilised visual approach to a runway with rather unforgiving terrain on its approach.

'At 1855:05 hrs the controller reported “…, field now eleven clock position, range six miles.“ The co-pilot answered that he had the airfield in sight after he had gotten the PIC's assurance.'

Had they instead flown a profile based on level vs distance numbers from their FMS, even at 300 ft per mile, they and their passengers would probably still be alive today.

[Jonzarno]

I don't really see how it can be described as anything other than a "home made approach" given that they descended out of whatever FL at which they had been cruising, and tried to fly what they thought was a straight in approach to an airport with no IAP in at best very marginal VMC. After all: if they really could see the airport, how did they come to be victims of CFIT?

Although I have no idea if this is true: a sceptic might conclude that when the controller asked if they could see the airport, they might have said yes in order to avoid getting into trouble because flight in IMC is not permitted in Germany unless on an IFR plan.

I agree that, had they followed the procedure you described, they might well have made it. Equally, that may have been what they were trying to do and they just got it wrong. Either way, they didn't get the indications that things were wrong that they would have had on a properly coded IAP.

That wasn't really the point I was trying to make, though, which was in reply to an earlier post: it was simply that there isn't always a black and white distinction between flights under IFR in airways and flights conducted completely in class G between non-instrument airfields.

[ShyTorque]

I don't really see how it can be described as anything other than a "home made approach" given that they descended out of whatever FL at which they had been cruising, and tried to fly what they thought was a straight in approach to an airport with no IAP in at best very marginal VMC. After all: if they really could see the airport, how did they come to be victims of CFIT?

That's not the same as an "unpublished letdown". It sounds like that crew were attempting to fly VFR in IMC, which is a totally different thing.

[Jonzarno]

Perhaps my choice of words wasn't all that it could have been: I think it is highly probable that they made an unpublished let down in order to start the home-made approach.

Again: this wasn't really the aspect I was trying to address in my earliest post, and I wasn't trying to reopen a discussion on this specific accident, only to use it to illustrate my original point.

[bookworm]

Again: this wasn't really the aspect I was trying to address in my earliest post, and I wasn't trying to reopen a discussion on this specific accident, only to use it to illustrate my original point.

Noted, and I'm sorry to pick on your post, but I think it illustrates the fundamental misconception in this thread.

After all: if they really could see the airport, how did they come to be victims of CFIT?

Really?! Welcome to the world of "night VFR", where you are required visually to avoid unlit obstacles and terrain at night.

There are two safety aspects to making any approach work where visual means are insufficient:

1) You need to plan to fly a trajectory that is clear of obstacles and terrain, with a margin consistent with the navigational performance of the system you are using. The trajectory also needs to be consistent with the performance of the aircraft.

2) You need to fly that trajectory with commensurate precision.

Approval and publication of an instrument approach procedure are designed to mitigate the risks associated only with aspect 1. You risk CFIT if you deviate significantly from a safe trajectory, whether or not that trajectory is PANS-OPS compliant, approved or published.

Throughout this thread, assertions have been made that, for example, "there are dead bodies and wreckage strewn all over the place" from the use of trajectories that have not gone through the rigours associated with PANS-OPS design, approval and publication. Yet the only accident examples cited are cases where the flight crew failed to fly a safe trajectory (whether published or not) with reasonable precision.

[foxmoth]

Agree, ANY approach, published or unpublished is unsafe if you do not fly it accurately.

[Jonzarno]

whether or not that trajectory is PANS-OPS compliant, approved or published.

I know that I'm getting sucked into the aspect of the thread that I was trying to avoid BUT........ :)

The point I was trying to make about approved vs home built approaches (and, to an extent as well, cloud break procedures) is that you get a much better indication that you are deviating from what you KNOW to be a safe profile on an approved IAP than on what you THINK is a safe profile on a home built approach.

There has been a thread about this running on PPL/IR which has divided opinion as well.

My own view is that, purely from a flyability standpoint, there is a world of difference between descending over the sea and then following a home built approach that you have programmed and stored into your NAV system and flown several times in VMC to test it to an airport with no hazardous terrain vs making up a descent and approach into a mountain airport when you get stuck in unexpected IMC.

Obviously, those examples represent the extreme ends of a spectrum of danger, and everyone has to decide where their comfort level lies.

[ShyTorque]

Jonzarno, I don't think anyone would argue with that and I don't think any one actually has, at least, not on this thread.

The main thrust of the argument here has been that some believe that descending below MSA in order to land is illegal if away from an aerodrome on a "published approach". It's not.

However, if a pilot chooses to do so, he /she is obviously "responsible for your own terrain clearance". Any ATCO will quite rightly make a point of telling you so at the time if you descend below his sector safe altitude.

[bookworm]

The point I was trying to make about approved vs home built approaches (and, to an extent as well, cloud break procedures) is that you get a much better indication that you are deviating from what you KNOW to be a safe profile on an approved IAP than on what you THINK is a safe profile on a home built approach.

How do you get "a much better indication"?

My own view is that, purely from a flyability standpoint, there is a world of difference between descending over the sea and then following a home built approach that you have programmed and stored into your NAV system and flown several times in VMC to test it to an airport with no hazardous terrain vs making up a descent and approach into a mountain airport when you get stuck in unexpected IMC.

I agree with that, and flyability is an issue. However, there's nothing difficult about setting up a safe trajectory into Egelsbach. You don't approach it down a valley. If you simply put in waypoints and calculate minimum levels to establish a 3 degree descent (preferably 4 degrees, but 3 degrees doesn't hit anything) then you fly a safe trajectory. That the Citation crew did not do that contributed to their demise. It would be possible to put an LPV into 27 at EDFE as far as the final approach segment goes: the problem is the missed approach segment and the conflict with 18 departures from EDDF, which is why there is no published approach.

[Jonzarno]

How do you get "a much better indication"?

Well on my aircraft, at least, it tells me if I am outside a guaranteed safe vertical and horizontal profile, when I have reached the MAP and shows my position on a geo-referenced approach plate.

Your other point is very interesting :ok:: I didn't know the reason for the lack of an IAP at Egelsbach. Given the point you make, I suppose it would have made for an interesting situation had the Citation flown what I assumed to have been a home made approach and then gone missed. Would they have ended up conflicted with EDDF traffic?

[bookworm]

Given the point you make, I suppose it would have made for an interesting situation had the Citation flown what I assumed to have been a home made approach and then gone missed. Would they have ended up conflicted with EDDF traffic?

In practice, with the performance of a Citation, no more practical risk of that than a missed approach in good VFR by day I would think. The EDDF CTR starts about a mile beyond the end of the runway. So turn away to the south and climb to about 1400 ft. But almost impossible to construct a turning missed approach in compliance with PANS-OPS, which assumes a 2.5% climb (150 ft per nm). I wouldn't be surprised if a Citation could exceed that by a factor of 5 to 10.

[Jonzarno]

Thanks for that!!

[alex90]

I recently chatted to a few IR and IR(r) students at various schools around London, some at fields without any published approaches over the last few weeks.

I was absolutely horrified when several of them told me that they had been taught to follow a "set of instructions to get back to the field safely in marginal conditions" which involved following radials from nearby VOR/DME. I asked how low they descended, and they told me a figure that sounded too low to be above MSA in these areas. I looked at them and paused for a minute... before asking what the MSA was in the area...

I am not only horrified to find out how many people would descend below MSA, but also at the fact that they were TAUGHT this! I find it absolutely crazy!

I then prompted them about doing a cloud break at a nearby aerodrome, and continue VFR, VMC the whole way back (note the difference between scud running); and some just retorted "why?" And others saying that they didn't even know they could do this!

I find this VERY worrying.

Anyone else think that this may be a good time to press the UK CAA to make GPS approaches more widely available at smaller airfields with/without ATC and make it more affordable paperwork-wise due to the HUGE safety increase provided? More and more IR/ IR(r) training planes being equipped with G430 / G430W / other glass - is it not time to start making approaches in the UK more widely available?

[blueandwhite]

I recently chatted to a few IR and IR(r) students at various schools around London, some at fields without any published approaches over the last few weeks.

I was absolutely horrified when several of them told me that they had been taught to follow a "set of instructions to get back to the field safely in marginal conditions" which involved following radials from nearby VOR/DME. I asked how low they descended, and they told me a figure that sounded too low to be above MSA in these areas. I looked at them and paused for a minute... before asking what the MSA was in the area...

I am not only horrified to find out how many people would descend below MSA, but also at the fact that they were TAUGHT this! I find it absolutely crazy!

I then prompted them about doing a cloud break at a nearby aerodrome, and continue VFR, VMC the whole way back (note the difference between scud running); and some just retorted "why?" And others saying that they didn't even know they could do this!

I find this VERY worrying.

Anyone else think that this may be a good time to press the UK CAA to make GPS approaches more widely available at smaller airfields with/without ATC and make it more affordable paperwork-wise due to the HUGE safety increase provided? More and more IR/ IR(r) training planes being equipped with G430 / G430W / other glass - is it not time to start making approaches in the UK more widely available?

I'm a bit surprised that you didn't realise the reality.

Yes GPS works to a different accuracy to old radio nav kit. The sooner the CAA gets modern approaches to more airfields the better.

[oggers]

Good Business Sense:
Do you fly in Class G or is it always on airways high level in something heavy?


Class G or class A it makes no difference. You cannot descend below the altitude approved by the state, which is either your safety altitude or the aerodrome minima if landing.

You present information/regulation relating to "aerodromes" to make your case - there is a whole world out there that doesn't fly to/from departure, destination and alternate aerodromes - your take on the LAW is out.

"Aerodrome" is defined in the regs as anywhere intended to be used for the arrival, departure or surface movement of aircraft.

ShyTorque:

There are obviously some here who still don't properly understand SERA 5015 (and its equivalent in the UK ANO in previous times). The "Safety Sense" leaflet, although giving advice, is not the legal definition. Check the wording of both.

I expect everyone understands 5015. What seems to be eluding you for some reason is that 5015 does not allow you ignore all the other regulations. SERA is not a complete stand-alone set of regulations, it is only a common core. If you go to the ANO and/or Part-NCO you find the other stuff a private pilot has to comply with.

The "Safety Sense" leaflet, although giving advice, is not the legal definition.

Let's call it what it is then. It is how the competent authority interprets their own legal definition :ok:

Here it is again:

"User-defined approaches can be dangerous and are not authorised."

And here are the current regs again:

ANO:For flights under Instrument Flight Rules, the pilot in command must select and use aerodrome operating minima for each departure, destination and destination alternate aerodrome which must not be lower than those notified, prescribed or otherwise designated by the relevant competent authority

Part-NCO:

For instrument flight rules (IFR) flights, the pilot-in-command shall select and use aerodrome operating minima for each departure, destination and alternate aerodrome. Such minima shall not be lower than those established by the State in which the aerodrome is located, except when specifically approved by that State

And here is the ICAO stuff it is based on:

ICAO Annex 6 2.2.2.2 Aerodrome operating minima:

The pilot-in-command shall not operate to or from an aerodrome using operating minima lower than those which may be established for that aerodrome by the State in which it is located, except with the specific approval of that State.

2.2.4.7.2 Aeroplanes operated in accordance with the instrument flight rules shall comply with the instrument approach procedures approved by the State in which the aerodrome is located.
Note that in no case is there a caveat that made-up minima can be substituted for approved minima even if you really really intend to land.

[ShyTorque]

Oggers, you are simply regurgitating what you wrote earlier. I do read the regulations, I'm very much aware of what they say.

I take it (looking at what you have written here and elsewhere on the forum) that you make most of your flights departing from a fully IFR equipped airfield, climbing to your MSA on a SID inside CAS and remaining so until your STAR and IFR letdown to a nicely lit runway. I have no issues with that although some don't have that privilege and there is a very different world outside of that type of operation.

Again, you are confusing the rules about airfield operating minima with other IFR rules. How do you think an IFR transit is done when operating from non-airfield sites?

[alex90]

I'm a bit surprised that you didn't realise the reality.


Well I assumed that everyone was taught well enough to know what they SHOULD do. Especially at IR(R) level. Ie... Descend to MSA, if you still can't see anything - request cloud base at a local aerodrome, if it is high enough to maintain VFR below, do a cloud-break approach. Then decide whether to commit to the approach, or to continue to your original destination VFR in VMC at or above the approach's minimums.

Not "follow X radial of VOR Y and at Z nautical miles DME continue descending below MSA". That is NOT what anyone should EVER do.

But then again, about 80% of them had never heard of an SRA... Sooooo.... Maybe I once again had too much faith in the teaching. Don't these instructors get taught how to teach? Don't they have renewals?

Anyway... How can we attempt to lobby the UK CAA for safer approaches for ALL airfields? I think this is particularly important right now, as we seem to have more and more accidents relating to people doing their own "ad-hoc" approaches. I find it very worrying. If at least these pilots, irrespective of pressures, had an alternative, then maybe there would be fewer accidents.

[Good Business Sense]

In almost everything you've just quoted the word aerodrome is included, yet again. What if you don't use aerodromes, I'm being serious - many operations don't ! I guess if you're nowhere near an airport your references don't count - maybe that's why 5015 is a standalone section of law?

For my sins, amongst may other technical manuals and publications, I've assisted with the writing of large sections of air law for three different countries - I'm happy to be corrected by a decent argument but until then I'll stick to my view.

One last thing - do you have a reference in law for, "User-defined approaches can be dangerous and are not authorised"? I know it was in a GA safety leaflet (you know my opinion of it) but there is no back up reference for the statement in law. Now, whether you think it is good airmanship or not, where is the law that underpins it ?

We're obviously from different schools so I'll leave you to it. No need to respond to the questions above.

All the best

[BEagle]

Apart from forced landings, all normal flying whether at London Airport or Farmer Giles' farm strip is at an 'aerodrome':

From ANO2016
“Aerodrome”—

(a) means any area of land or water designed, equipped, set apart or commonly used for affording facilities for the landing and departure of aircraft; and

(b) includes any area or space, whether on the ground, on the roof of a building or elsewhere, which is designed, equipped or set apart for affording facilities for the landing and departure of aircraft capable of descending or climbing vertically; but

(c) does not include any area the use of which for affording facilities for the landing and departure of aircraft has been abandoned and has not been resumed;

[alex90]

What if you don't use aerodromes

I think this is where the definition of an aerodrome becomes important. If you don't use an aerodrome, then technically, you can't be flying. An aerodrome is usually defined as: "An aerodrome or airdrome is a location from which aircraft flight operations take place, regardless of whether they involve air cargo, passengers, or neither." So if you takeoff or land somewhere, where aircraft flight operations don't take place - well... They are technically taking place during your event (as your event of takeoff / landing is construed as a "flight operation"), and therefore would be bound by the same rules and regulations.

I am not an expert in law, nor in Instrument Flight Rules, nor do I wish to entertain the possibility of having someone who is properly trained to fly under IFR, do something so reckless and dangerous. IAP exist for a reason, they are very stringent for a reason. The scary thing is that we all know the reasons why - and yet we are still discussing and entertaining this possibility as a "normal" occurrence which I find greatly worrying!

I think you will find that you have ample available reading regarding MSA.

[Good Business Sense]

It's important not to pull words out that you like from a sentence/para - it needs to be read in full i.e. in context - below para C helps my point - i.e. even a disused airport does not count ?

“Aerodrome”—

(a) means any area of land or water designed, equipped, set apart or commonly used for affording facilities for the landing and departure of aircraft; and

(b) includes any area or space, whether on the ground, on the roof of a building or elsewhere, which is designed, equipped or set apart for affording facilities for the landing and departure of aircraft capable of descending or climbing vertically; but

(c) does not include any area the use of which for affording facilities for the landing and departure of aircraft has been abandoned and has not been resumed;

For example, there are many more, when a police helicopter lands in a field or on a road or when a rescue helicopter lands on a rock shelf half way up a mountain does that make it an aerodrome .... I would say no as it's ;

not designed for;
not equipped for;
not set apart for;
not affording facilities for;


For info MSA

One Definition;

The Minimum Sector Altitude (MSA) is the lowest altitude which may be used which will provide a minimum clearance of 300 m (1 000 ft) above all objects located in the area contained within a sector of a circle of 46 km (25 NM) radius centred on a radio aid to navigation.

- Normally quoted around an airfield (found at the top of most IFR charts) - sometimes cut into different sectors with different altitudes quoted.

[alex90]

i.e. even a disused airport does not count But.... The landing or departure of aircraft HAS been resumed - because you have landed there, despite it generally being marked as "disused".

not designed for;
not equipped for;
not set apart for;
not affording facilities for; One could argue - even in your rather extreme case, that if nothing else, the aircraft (irrespective of type) has been able to land, therefore, in context, as you suggest, the landing site chosen "afforded" the aircraft thus being a suitable location for such purpose.

ps: sorry for splitting hairs - this doesn't amend the fact that MSA in the "class G, IR(R) world" generally means Minimum Safety Altitude, which relates to being at least 1000' above the highest obstacle within 5nm of track.

[Good Business Sense]

Alex90

Extreme case?

Happens hundreds of times per week in the UK

fact that MSA in the "class G, IR(R) world" generally means Minimum Safety Altitude

Re. splitting hairs - in the Commercial Class G IR world MSA relates to my post above and has nothing to do with class G per se and, as far as I'm aware, there is no official term such as "Minimum Safety Altitude" i.e. no definition, ICAO or otherwise. I'm sure many people use these aberrations in various ways but they mean nothing in themselves and they are incorrect.

relates to being at least 1000' above the highest obstacle within 5nm of track

Once again, the importance of quoting the entire law i.e. all the text ..... The RULE is as follows .... you've left out ..... "Except when necessary for take-off or landing"

SERA.5015 Instrument flight rules (IFR) — Rules applicable to all IFR flights
(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 (1), 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.


I think we've done this to death now - I'm done - happy landings

[oggers]

Good Business Sense:

In almost everything you've just quoted the word aerodrome is included, yet again. What if you don't use aerodromes, I'm being serious - many operations don't !

As I pointed out when you posted that objection the first time, it is the generic term in the regulation for anywhere that you take-off or land.

Here is are the actual definition from ICAO:

A defined area on land or water (including any buildings, installations and equipment) intended to be used either wholly or in part for the arrival, departure and surface movement of aircraft.

And from SERA:

aerodrome’ means a defined area (including any buildings, installations and equipment) on land or water or on a fixed, fixed off-shore or floating structure intended to be used either wholly or in part for the arrival, departure and surface movement of aircraft;

As far as the regulations about aerodrome minima go there is nothing in the regs that require the 'aerodrome' to be anything more than the place you intend to land, be it a field, or a flight deck. And in case you are wondering I am familiar with operating from such sites.

You and ShyTorque are both in error in believing that the regulations pertaining to aerodrome minima do not apply to sites that are not - to use the vernacular - 'airports'. But wouldn't it be a nice get out of jail card to play. 'Technically I didn't bust my minimums because I was actually making an approach for the purpose of landing iaw SERA 5015 in the field next to the airport and therefore minima do not apply'.

For my sins, amongst may other technical manuals and publications, I've assisted with the writing of large sections of air law for three different countries - I'm happy to be corrected by a decent argument but until then I'll stick to my view.

It makes no difference to me how many technical manuals or legal documents you claim to have written. It is the stuff you are writing here that is in error.

[Good Business Sense]

"Defined" - Past tense

CAP793
The regular use of an area of land or water for aircraft take-offs and/or landings amounts, in law, to the establishment of an aerodrome.

[ShyTorque]

Oggers, I refer you again to the text from the AAIB report I quoted in post #105.

There was no comment from the CAA on that recommendation and there has been no change under SERA to the regulations that were in force at that time.

Enjoy your airline flying and ILSs.

[foxmoth]

I think this is yet another of those arguments that will only be properly answered if someone ends up in court and a judge makes a ruling!

[oggers]

ShyTorque

Oggers, I refer you again to the text from the AAIB report I quoted in post #105.

You are really clutching at straws. That pre-dates all the current regs. What an AAIB inspector thought might have been legal in 2009 is a very tenuous basis for rejecting the current regulations and advice from the CAA that has all undergone a major change since the report's recommendation to close off that particular loophole. It doesn't occur to you that the recommendation was acted on or perhaps rendered moot by the intro of EASA Ops.

Oggers, you are simply regurgitating what you wrote earlier. I do read the regulations, I'm very much aware of what they say.

I take it (looking at what you have written here and elsewhere on the forum) that you make most of your flights departing from a fully IFR equipped airfield, climbing to your MSA on a SID inside CAS and remaining so until your STAR and IFR letdown to a nicely lit runway. I have no issues with that although some don't have that privilege and there is a very different world outside of that type of operation.

Again, you are confusing the rules about airfield operating minima with other IFR rules. How do you think an IFR transit is done when operating from non-airfield sites?

This thread is about unpublished let-downs for private pilots. There is no confusion, the regulations on aerodrome minima apply to IFR approaches (whether the 'aerodrome' happens to be a field or a proper airport). This from the UK AIP has not previously been "regurgitated":

4.12 Aerodromes Without Published Instrument Approach Procedures
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.
I don't see how the CAA could spell it out any more clearly than that.:ugh:

[oggers]

Good Business Sense

Quote:
"Defined"
- Past tense

CAP793
The regular use of an area of land or water for aircraft take-offs and/or landings amounts, in law, to the establishment of an aerodrome.

Ha! You are having a laugh! The definition in SERA and ICAO annex 6 is current.

I see what you have done though, you have conflated what constitutes an aerodrome for the purposes of licensing (CAP793) with what constitutes an aerodrome for the purposes of determining aerodrome minima. I salute your audacity :ok:

...but what constitutes an aerodrome for the purpose of determining aerodrome minima is still any place used for the departure, approach or surface movement of aircraft. As per the still current definition used in Part-NCO as well as SERA and ICAO annex 6.

[bookworm]

It doesn't occur to you that the recommendation was acted on or perhaps rendered moot by the intro of EASA Ops.

It's EASA Air Ops that's the issue here. Allow me to quote some snippets:

CAT.OP.MPA.125 Instrument departure and approach procedures
(a) The operator shall ensure that instrument departure and approach procedures established by the State of the aerodrome are used.
(b) Notwithstanding (a), the commander may accept an ATC clearance to deviate from a published departure or arrival route, provided obstacle clearance criteria are observed and full account is taken of the operating conditions. In any case, the final approach shall be flown visually or in accordance with the established instrument approach procedures.

NCC.OP.115 Departure and approach procedures
(a) The pilot-in-command shall use the departure and approach procedures estab*lished by the State of the aerodrome, if such procedures have been published for the runway or FATO to be used.
(b) Notwithstanding (a), the pilot-in-command shall only accept an ATC clearance to deviate from a published procedure:
(1) provided that obstacle clearance criteria are observed and full account is taken of the operating conditions; or
(2) when being radar-vectored by an ATC unit.
(c) In any case, the final approach segment shall be flown visually or in accordance with the published approach procedures.

NCO.OP.115 Departure and approach procedures — aeroplanes and heli*copters
(a) The pilot-in-command shall use the departure and approach procedures estab*lished by the State of the aerodrome, if such procedures have been published for the runway or FATO to be used.
(b) The pilot-in-command may deviate from a published departure route, arrival route or approach procedure:
(1) provided obstacle clearance criteria can be observed, full account is taken of the operating conditions and any ATC clearance is adhered to; or
(2) when being radar-vectored by an ATC unit.

Note the conspicuous absence of NCO.OP.115(c). Just in case you think it's an accidental omission, here's the corresponding bit from SPO, which tends to deal with both complex motor-powered aircraft and non-complex aircraft:

SPO.OP.115 Departure and approach procedures — aeroplanes and heli*copters
(a) The pilot-in-command shall use the departure and approach procedures estab*lished by the State of the aerodrome, if such procedures have been published for the runway or FATO to be used.
(b) The pilot-in-command may deviate from a published departure route, arrival route or approach procedure:
(1) provided obstacle clearance criteria can be observed, full account is taken of the operating conditions and any ATC clearance is adhered to; or
(2) when being radar-vectored by an ATC unit.
(c) In the case of operations with complex motor-powered aircraft, the final approach segment shall be flown visually or in accordance with the published approach procedures.

[alex90]

I am with Foxmoth on this... Sounds like a neverending argument...

Law or not; Just don't be stupid. Value your life and those of others both in and out of the aircraft. Don't descend below MSA (irrespective of your definition) unless you're on an IAP or in VMC remaining visual until you touchdown.

HAVE COMMON SENSE. Live to fly, don't fly to die!!!

[oggers]

Yes bookworm I agree that part of the regs permits a deviation from published procedures which could be interpreted as permitting a user defined approach all the way from safety altitude to landing. I think it is the only place in the regs where the argument that non-approved approaches are legal has any basis. But the problem is it is contradicted by so much of the other regs and information from the CAA that I have already posted.

One thing that is definitely a red-herring is the notion that a landing site is not subject to the regs pertaining to aerodrome operating minima if it is not a proper airfield. And another red-herring is that ad-hoc descent below safety altitude in IMC is permitted on the basis of SERA 5015. But that one you posted above does on its own merit suggest that an unpublished let-down might be legal for non-complex, non-commercial operations.

[Sillert,V.I.]

Law or not; Just don't be stupid. Value your life and those of others both in and out of the aircraft. Don't descend below MSA (irrespective of your definition) unless you're on an IAP or in VMC remaining visual until you touchdown.

That.

However much folks may argue about the legal interpretation of the rules & regulations, historically enforecement has generally been the province of a higher authority whose judgment is instant, final, unforgiving and not subject to appeal.

[bookworm]

However much folks may argue about the legal interpretation of the rules & regulations, historically enforecement has generally been the province of a higher authority whose judgment is instant, final, unforgiving and not subject to appeal.

You've said that twice now, but I'm still waiting for an example where that instant, final, unforgiving judgment was passed on the design of the approach rather than its execution.

[ShyTorque]

Oggers, again, you regurgitate the same wording that is available to all. Again, the term "should" has never prefaced a mandatory item.

"Should" indicates advice. If the wording read "shall" or "must" I would agree it was mandatory. But it doesn't, even under framework of SERA, which you rather strangely seem to think I haven't read.

The new regulations have had a very significant effect on certain parts of the U.K. industry. Thankfully the CAA have listened to the coal face in a number of areas and gave allowed certain easements. I'm grateful to have been asked for my personal input in a couple of areas in that regard. This (topic under discussion) is one area where SERA has not imposed further restrictions, despite Oggers thinking otherwise.

However, I most definitely wouldn't ever advise any pilot, "private" or otherwise (SERA doesn't differentiate, Oggers) to descend below MSA on a whim, for obvious safety reasons and I certainly would not do so. IFR flights need to be very carefully planned with nominated diversions found as necessary. That latter requirement remains in the ANO, but it rather strangely states:

"If, according to the information available, an aircraft would as regards any flight be required to be flown in accordance with the Instrument Flight Rules at the aerodrome of intended landing, the pilot in command of the aircraft must select before take-off a destination alternate aerodrome unless no suitable aerodrome suitable for that purpose is available.

The text I have quoted in bold would rather tend to lead a pilot into the very situation we are discussing! The only possible reason for that wording isn't immediately obvious, but it allows a pilot to use judgement on a forecast weather clearance, such as early morning fog. My personal judgement would be not to take such a risk.

That is a separate issue to the legality of a descent below MSA when necessary to do so in order to land, iaw SERA 5015.

What hasn't really been discussed fully is what constitutes a published approach/letdown and what doesn't. For example, the meaning, in legal terms, of "published". In the past I've been given details of a number of approaches designed and fully surveyed by a CAA recognised expert which the CAA has been fully aware of. You won't find them in any flight guide or the AIP. Some of them are for easily recognised airfields and some are not. Where might an approach be classed as "published" and where might it otherwise exist?

[ShyTorque]

You've said that twice now, but I'm still waiting for an example where that instant, final, unforgiving judgment was passed on the design of the approach rather than its execution.


However much folks may argue about the legal interpretation of the rules & regulations, historically enforecement has generally been the province of a higher authority whose judgment is instant, final, unforgiving and not subject to appeal.

Bookworm, I think he's referring to final judgement passed by smiting the earth! ;)

But a published approach, flown badly, is also highly likely to suffer the same consequence.

[Sillert,V.I.]

You've said that twice now, but I'm still waiting for an example where that instant, final, unforgiving judgment was passed on the design of the approach rather than its execution.

The devil is usually in the execution (perhaps an appropriate choice of word in this case?). Sadly arguing about whether they crashed because of a failure in the design of a homemade approach, or its subsequent execution, doesn't change the fact that they're now dead.

There are plenty of examples of a badly executed approach where disaster has been averted only because of the additional safeguards built into operating in a properly regulated and controlled environment.