unofficial use of landing aids

[bogbeagle]

I'm fairly confident that 'tis unlawful to, say, slide down an ILS when the appropriate controllers are not on watch, i.e when the airfield is closed. However, I can't find the relevant bit of the ANO which does preclude such actions. Can any of you guys point me in the right direction.

Springer

[chevvron]

Depends where it is I suppose; if it's at an airport in class D airspace, it could well be illegal. If a guy is IMC and IFR, they could well go below safety altitude and lose terrain clearance thereby 'knowingly or recklessly endangering the safety of an aircraft'. Likewise if it's over a built up area, unless they're taking off and landing iaw normal aviation practice (which they won't be as they are not intending to land), they break the law if they go below 1000ft above the highest fixed object etc.
At my airfield, we've had complaints about aircraft landing outside the permitted hours. Well we know they aren't, and the aerodrome authority believe it may be people doing what you say, so the ILS is now switched off when the airfield closes.

[Chilli Monster]

The Relevant bits are:

Article 103
In the case of an aerodrome (other than a Government aerodrome) in respect of which there is equipment for providing aid for holding, aid for let-down or aid for an approach to landing by radio or radar, the person in charge of the aerodrome shall:
(a) inform the CAA in advance of the periods during and times at which any such equipment is to be in operation for the purpose of providing such aid as is specified by the said person; and
(b) during any period and at such times as are notified, cause an approach control service to be provided.

And

Rule 40
(1) Subject to paragraph (2), the commander of an aircraft shall not make use of any radio navigation aid without complying with such restrictions and appropriate procedures as may be notified in relation to that aid unless authorised by an air traffic control unit.
(2) The commander of an aircraft shall not be required to comply with this rule if he is required to comply with rule 31.

[SoftTop]

There's also the small issue of using a potentially unmonitored aid. ILS, to the best of my knowledge (limited to UK) is not generally monitored by ACCs and if there's no ATCO in the VCR watching the indications, I don't think I'd be too happy about using it.

The monitoring requirements are in CAP670 for the UK, and ICAO Annex 10 give the minimum international requirements - don't have time to browse them at the moment. I haven't found the ICAO annexes on the internet yet. I'm pretty sure you have to buy them.

ST

[Spitoon]

It's a bit old and the ANO has been updated since but in this (http://www.caa.co.uk/docs/33/ATS000.pdf) there's some stuff aimed at airport operators that might be of relevance.

[Scott Voigt]

We do this all the time in the US... There is no need to have a tower open or even have one to use an approach such as an ILS. You can also use it without ATC approval if conditions are VMC and you will not enter IMC and just want to practice...

regards

Scott

[Pierre Argh]

Scott, be careful you sound like you're advocating the "it's OK because we do it in the US!" strategy. What I would ask you, and all other readers to consider is serviceability.

There is no reason why maintenance of the ILS cannot be carried out outside normal airfield opening hours, and as far as I'm aware (in the UK) no reason to notify the effect providing the equipment will be returned to use before next time the airfield is open (becasue using said kit is against regulations).

Secondly, many ILS installations require protection (i.e. ground movements adjacent to the ILS aerials are monitored & controlled when the equipment is in use)... when the airfield is closed there may be no need to control these movements, hence a serviceable ILS signal may be interfered with... and you'd be none the wiser in the cockpit :-(

Basically... a dodgy procedure I would strongly not recommend.

[niknak]

I recall a very experienced flying instructor doing precisely this at a UK airfield when it was closed, his student flew the ILS perfectly and at decision height went around... only to meet someone who was doing exactly the same thing after executing an instrument approach on the recipricol runway.

I believe that both sets of pilots went away to contemplate in a dark room for a while and then considered the dry cleaning bill for their respective underwear.

[Scott Voigt]

PA. In the US if you are going to take a navaid out of service for any reason then a NOTAM must be filed and pilots are required to get them prior to flight... Also if they are going to take it off the air for maint. then they must take the ident off too... Just one of those things that we are taught to check over here.

regards

Scott

[West Coast]

Always check the ID of the navaid prior to using.

No signal or test signal = don't use

"Basically... a dodgy procedure I would strongly not recommend"

Happens thousands of times a day, ranging from GA to air carrier to mil. Nothing dodgy about it.

[Pierre Argh]

Nothing dodgy about it.... obviously a matter of opinion!

West Coast, are you writing off Niknak's account as simply improbable?

Scott you're right about idents etc will help, but it doesn't rule out interference with the beam... (Not sure are required to NOTAM removal of a piece of kit designed for solely for airfield use when that airfield is closed... but it might be?)

We'll leave you Yanks to get on with it at your peril... (hopefully you will at least consider these cautionary tales before doing it next time?)... simple fact it is against CAA Regs and must not be attempted in the UK.

[discountinvestigator]

It is an ICAO requirement for the approach controller to have the status of all approach navigation aids displayed in a relevant position.

It is usually the approach controller (procedural or radar) that gives the clearance to use the approach aid, not the tower controller, as the ratings are different.

It is also a requirement for the tower controller to have the status displayed.

Use of the navigation aid outside published hours is prohibited in England, Wales and Northern Ireland under the conditions mentioned. You require an ATC clearance to use the navigation aid, which you cannot have if the aerodrome is closed.

There are certain aerodromes in Scotland where use of navigation aids for instrument approaches is allowed, and no ATC service is provided. However, this is a very very grey area of the law, and restricted to a few aircraft operators only, mainly Loganair.

Interestingly enough, use of navigation aids to approach many offshore installations might be illegal as well! Nice to see that SRG and DAP cannot agree on this, but the "Authority speaks with one voice".

Interesting interpretations would occur when using en-route navigation aids, based at an aerodrome that is either closed, or does not have an ATC service. Not that I am suggesting that anyone still has the old plates for Goodwood, for example.....

There is an interesting exception to the Tower ATC function which occurs at Lasham. There is approach control, but no tower ATC, from memory at least, please correct if wrong! They give you an SRA to 2 nm and then it is up to you.

The controllers have "remote indication" in their respective dark holes or greenhouses. The equipment has monitoring provided with it. Most modern navigation aids will shut down automatically if the system is close to the tolerance boundaries. What you will not notice is some distortion of ILS signals if only a near field monitor is in use and then someone parks a 747 in front of the remaining GP signal. That will make you fly at about one degree, not three. Many navigation aids have two channels, so that if the A system fails, the B takes over. In the event of a major problem, or single source failure point, then the whole lot should stop transmitting.

Remember, that you need the identity, not TST for those who cannot interpret morse!

Remember about ASSOCIATION of identity signals as well. The group of four identity tones for a VOR/DME. Now, which way round is it... three for the VOR and one for the DME.... well, you should know.... if only listen for one then it does not tell you all you need to know.

As for the opposite direction stuff, well fine for VOR or NDB, but the LOC signals would interfere with one another, so they are interlocked out so only one end can transmit at once.

I guess in summary, for flying in the UK, only during published hours, with ATC clearance!

[West Coast]

How can you turn it into a Yank thing? If its safe and and done in the middle of Africa would it change your tone?
What it does have is a large body of evidence indicating that it works over here. If your regs say your not allowed, then follow your regs. Understand just because the way its done elsewhere in the world differs from your system doesn't make it dangerous, just different.

[tori chelli]

Discountinvestigator...what's your reference for saying "use outside published hours is illegal in the UK"?
I agree it's not sensible, but illegal??
Chilli points us to the salient articles of law, but to answer bogbeagle's question and play devil's advocate for the moment...
Article 103 says the provider has to a) notify times and b) provide a service therein...OK so he/she does, but unlike chevvron, leaves the power on to the facility after hours
Rule 31. 3)a)ii)bb) says the commander has to fly in accordance with the notified procedures...ident the beacon, follow the plate and tick that box
Rule 40 1) says the commander must follow the appropriate procedures...again; ident the beacon, follow the plate and tick that box
so if the operator has left the power on and we do what we're supposed to do but after hours, I'm thinking that foolish as it may be, we're getting towards what Scott & his buddies do all the time.
using the CFD VOR as an example, it's an H24 en-route aid and provides an approach to the airfield...why are the plates suddenly unsafe because it's after 19:00 ?
Tori

[Scott Voigt]

PA;

If they do ANYTHING to the navaid or the landing surface then they have to NOTAM it and it should get to both the controller and pilot.. Now that said, what are you going to do for a GPS approach which has nothing to do with a navaid at the airport <G>????

regards

Scott

[Say Again, Over!]

NikNak,

If two airplanes are shooting approaches to an uncontrolled aerodrome at opposite ends and never know of each other until they meet over the field, then someone didn't make the mandatory calls on the local frequency.

As is the norm in Canada (where I am), I would suspect that an airport deserving of an ILS or at least an instrument approach, would also have a mandatory frequency for afterhour use.

Now, on a more serious note: Do you really have your underwear drycleaned? :eek::}

SAO

[discountinvestigator]

Discountinvestigator...what's your reference for saying "use outside published hours is illegal in the UK"?

Article 104 (1) A person shall not cuase or permit and air traffic service equipment to be established or used in the UK otherwise than under and in accordance with an approval granted by the CAA to the person in charge of the equipment.

Article 104 (3) (a) The person in charge of an aeronautical radio station at an aerodrome for which a licence for public use has been granted shall cause to be notified in relation to that aeronautical radio station the type and availability of operation of any service which is available for use by aircraft.

OK, so for aerodromes with licensed for public use with navigation aids located there (almost, but not exclusively all of them. Scatsta, Southend and a few others might not be public use licence but ordinary, in fact Coventry springs to mind as well, but I do not have any sort of official list and do not have time to plod through the AIP trying to work it out) then the hours of service have to be published.

The approved service will include written conditions from the CAA in relation to the provision of full ATC at the time. Therefore, in unwritten terms, or at least invisible to flight crew, you have a requirement to be open and providing ATC for instrument approach procedures to be valid.

Now, if you want to stir up a hornets nest in this area, just ask CAA SRG Flight Operations, Aerodrome and ATC as well as CAA Directorate of Airspace Policy and the corporate legal branch to agree on it. Even if questions were not asked in Westminster, sure as hell they would be asked in Edinburgh at the Scottish Parliament when all the procedures for the outer islands and offshore installations go!

[vector4fun]

In many cases in the U.S., Instrument Approach systems are remotely monitored (via computer systems) at a regional office, which will call the affected ATC facilities should a fault be noted. While we have ILS monitors in our Tower cab, they are also remotely monitored from the same office. We have a satellite field with ILS, several NDBs, and the area VOR which are not monitored at all from my facility, but from said regional office. In absense of a phone call, or report from pilot that facility ID is missing, we run approaches to those satellite airports. In VMC wx, it is not unusual at all to see several VFR targets flying practice approaches to same without communicating with ATC. I'm sure they are, (or SHOULD) be communicating on the common traffic advisory frequency (CTAF) however.

Been that way over here for decades. I was doing same in the early '70s while working on my Instrument rating. :hmm:

[Pierre Argh]

Once again we have a topic that highlights differences across the world (a bit worrying in an international game such as aviation...) It is clear that use of approach (not nav) aids outside A/.F hours is illegal under UK regs ... fact.

That the Americans (and possibly others across the world) do differently doesn't change that... nor does it change the interpretation UK experts placed on the practise that is is... shall we say "unwise". To mis-quote your comment back at you... Understand just because the way you do it differs from our system doesn't make it safe either, just different
This is not an attempt at Yank bashing... did I strike a nerve there Westcoast? This thread is based on an an enquiry about UK practices; it is, perhasp, foolhardy to cloud the issue by talking about International practices that may not apply? However it was, I think, Douglas Bader who said, "Rules are for the obeyance of fools and guidance of wisemen". Quite typically some have highlighted "exceptions" UK where rules are being "bent" or "ignored" across the UK... if you're insistent upon following suite, and needs must... best practice may be to (as is probably the case with the airfields/operators quoted) check with the unit in question before flight, check their practices when closed and their feelings about said practices (may have to be off the record)

... and as, no doubt Scott and Westcoast would say, "Y'all be careful y'hear!" Alternatively, maybe the aids should be turned off with the airfield lights?

[West Coast]

You do it your way and I'll continue to safely do it our way.

[bookworm]

So what's the difference, under Rule 40, between flying down an ILS and using an off airways VOR or NDB for navigation outside controlled airspace?

[goddammit]

I believe tori chelli has got it right.

If the airfield is closed, then there is no atcu to authorise anything other than the notified procedure.

The airfield operator has to publish when a service is available, but outside those hours they are not required to turn the facility off, at least not in the 2 approvals i've read.

[PPRuNe Radar]

The UK and the US are not all that different as I read it.
In the US, you can carry out an approach using the aids of a closed airfield without any ATC clearance at any time if flying VFR. Exactly the same as in the UK :ok:

In the US, if you are IFR, you need an ATC clearance (from the Tracon or Center if the airfield ATC facility is not available). In the UK, you also need an ATC 'clearance'. The only difference is that the Area Control Centres in the UK can't give you one so there is no possibility of legally making an approach in IFR at an airfield which is closed (except with special procedures agreed with the CAA by individual operators).

Scott or West Coast, correct me if my simplistic view is wrong please :ok:

[bookworm]

In the US, you can carry out an approach using the aids of a closed airfield without any ATC clearance at any time if flying VFR. Exactly the same as in the UK :ok:

Rule 40 makes no distinction between VFR and IFR.

[PPRuNe Radar]

Bookworm

You have to apply lateral thinking to get to a VFR exemption from the Rule ;)
Rule 40 states:

Use of radio navigation aids

40 (1) Subject to paragraph (2), the commander of an aircraft shall not make use of any radio navigation aid without complying with such restrictions and appropriate procedures as may be notified in relation to that aid unless authorised by an air traffic control unit.

(2) The commander of an aircraft shall not be required to comply with this rule if he is required to comply with rule 31.

So if we jump to Rule 31 :

Flight plan and air traffic control clearance

31(1) In order to comply with the Instrument Flight Rules, before an aircraft either takes off from a point within any controlled airspace or otherwise flies within any controlled airspace the commander of the aircraft shall cause a flight plan to be communicated to the appropriate air traffic control unit and shall obtain an air traffic control clearance based on such flight plan.

(2)Not included - not relevant to this thread.

(3) (a) subject to sub-paragraph (b), the commander of the aircraft shall fly in conformity with:

(i) the air traffic control clearance issued for the flight, as amended by any further instructions given by an air traffic control unit; and

(ii) (aa) the instrument departure procedures notified in relation to the aerodrome of departure unless he is otherwise authorised by the appropriate air traffic control unit; and

(bb) the holding and instrument approach procedures notified in relation to the aerodrome of destination unless he is otherwise authorised by the appropriate air traffic control unit.

(b) The commander of the aircraft shall not be required to comply with subparagraph (a) if

(i) he is able to fly in uninterrupted Visual Meteorological Conditions for so long as he remains in controlled airspace; and

(ii) he has informed the appropriate air traffic control unit of his intention to continue the flight in compliance with Visual Flight Rules and has requested that unit to cancel his flight plan.

So, if someone files IFR with any portion of flight in CAS, but then cancels to go VFR (perhaps doing so with an En Route ATC agency or a FIS service, not necessarily the airfield ATC unit), they do not need to comply with Rule 31 Para 3 (a) but only Rule 31 Para 3 (b). By complying with the relevant part of Rule 31, they can be exempt from Rule 40 :ok: It may not be the intention, but the relevant part of Rule 31 doesn't state that you have to remain in CAS at the point where you are using the navaid, does it ??

In other words, I could depart from Bristol IFR (in CAS), comply with relevant clearances until clear of CAS, cancel IFR and go VFR with London Info, and then make a VFR approach using the navaids at Shoreham (which is closed). It would all be down the the legal interpretation of what would be an 'appropriate ATS unit' to cancel the IFR plan with, thus allowing me exemption from Rule 31 Para 3 (a) and subsequently Rule 40. I would argue that London Info is an 'appropriate' unit to do so with. I suspect the CAA mean it to be an appropriate ATS unit related to the navaid, but as this is not implicitly stated, it is arguable in court.

For someone flying VFR the whole way, or flying IFR wholly outwith CAS before going VFR whilst still outside CAS, it is perhaps not as clear cut, but there are certainly things a good aviation lawyer could pick up on to argue with :D

[goddammit]

Sounds to me it would be easier to just go ifr :)

[Pierre Argh]

PPRuNe Radar... I think I managed to follow your logic, convaluted though it was. One question, just because there is a legal defence (albeit questionable as you yourself admit), do you think that makes the practice of such a manouevre sensible in light of the cautionary tales that have been posted?

[tori chelli]

Pprune Radar - sir :)

Most of your answer referred to IFR in CAS as detailed in Rule 31. I still maintain that the law is being followed if you fly the notified procedure to an out-of-hours airfield in the FIR (ATZ not existing out-of-hours) if the navaid is still powered up and idents correctly. I still refer to the CFD VOR which, if memory serves, is an en-route navaid operated by The Authority, but happens to have an airfield approach procedure stuck onto it.

Discountinvestigator
I still think a CAA VOR facility operating H24 covers Art 104 1)...as to conditions specifying use for approaches under 104 3) I couldn't say:\

Goddamit...thank you, it's not often someone thinks I'm right :D :D

I'm not suggesting it's clever, or that I'd want to do it, but for theory's sake...

[PPRuNe Radar]

Perfectly safe in respect of the US way (which I was defending as being not too disimilar to the UK) and also the UK.

In VFR (and thus VMC) you can see the ground. Using an aid does not prevent that. Legally whether you can use an aid which no one can check up on whether you did or not is another issue. I think that is the same for the USA and the UK (by inference).

In IFR, the US requires you have a clearance from someone. I don't know their rules well enough to say if there is a VMC differential whilst under IFR.

In the UK, under IFR you need an ATC clearance, except in the specific occasions mentioned in the ANO. These conditions are when you are flying in IFR and then switch to VFR (and thus VMC) or when you can fly in uninterrupted VMC (remaining IFR) in CAS. Again, using an aid does not prevent you seeing the ground.

So both are perfectly safe systems in my opinion.


IFR and IMC in UK = No go without ATC clearance. Only available from airfield ATSU.
IFR and VMC in UK = OK, if you are in CAS, or cancel IFR plan.
VFR and VMC in UK = OK at all times.

[FlyingForFun]

Interesting thread, from a pilot's point of view. Especially from an instructor's point of view - I often have reason to fly instrument approaches in VMC (for training) and it's good to know what I can and can't do.

Can I ask for your thoughts on the following related issue? A hypothetical airport in Class G is occassionally short of staff, and is not able to provide any form of approach control service for short periods due to not having appropriately qualified controllers.

If I want to fly an instrument approach, in VMC, the tower controller is not able to clear me for the approach because he is not qualified to do so. But he is happy, and might even pass me traffic information, if I inform him that I will be "general handling in the overhead at 3000'" and I then fly something which looks suspiciously like a hold. Likewise, I can then inform him that I will be "general handling to the east of the airfield", and then that I am "6 mile final" for the westerly runway, from which point he will clear me to land, touch+go, or low approach and go around as appropriate. Has anyone broken any rules?

How about the same situation in IMC, notwithstanding the fact that I have no method of avoiding conflicting traffic?

FFF
-------------

[Chilli Monster]

Having previously worked at such an airport it's not as hypothetical as you infer ;)

VMC - Provided neither of use any words that infer that an instrument approach aid is being used then no problems at all - because you're not are you. Once you say something (remember - it's all taped) then you drop yourself (and possibly said ATCO if they 'go along' with it) in the pooh.

IMC - the same applies. After all, he's not in the aircraft - you are. Therefore said ATCO, although the weather conditions they report might intimate IMC, doesn't actually know you're IMC where you are.

It's a matter of conscience really.

[PPRuNe Radar]

Tori Chelli
Basic flaw in your post ..... the CAA don't operate any navaids :p

However, I agree with you that it could be interpreted that flying an approach published in the AIP (regardless of ATC availability) might comply with Rule 40. I need to take counsel on that though ;)

[bookworm]

Perfectly safe in respect of the US way (which I was defending as being not too disimilar to the UK) and also the UK.
I think we can agree the US experience demonstrates that the risks of using aids without a clearance, particularly in VMC, are quite limited. Other than that, I think I'll refrain from the suggested "lateral thinking". ;)
Rule 40, and in fact much of the UK attitude to IAPs at smaller airports, is both vague and hopelessly out of date.
It's a matter of conscience really.
i.e. anything's legal as long as you don't get caught? ;)

[Spitoon]

PPRUNE Radar Don't know whether this makes much difference to your argument but ‘Appropriate air traffic control unit’ is defined in the ANO as "in relation to an aircraft either the air traffic control unit serving the area in which the aircraft is for the time being, or the air traffic control unit serving the area which the aircraft intends to enter and with which unit the aircraft is required to communicate prior to entering that area, as the context requires". The phrase "with which unit the aircraft is required to communicate" might be a problem but I agree that it all comes down to an interpretation.

[funfly]

There's an interesting thread elsewhere about the effect of interference (by vehicles) on ILS. An interference will result in the ILS unit being unusable and immediately switched off.
Presumably before entering the localiser our pilot (who will not have advised ATC) will have morse identified it. If there is then a problem with the ILS during his approach there will be no way of the ATC advising the pilot of this fact if they (the ATC) are unaware that the pilot is using the ILS.

[foghorn]

There's an interesting thread elsewhere about the effect of interference (by vehicles) on ILS. An interference will result in the ILS unit being unusable and immediately switched off.
Presumably before entering the localiser our pilot (who will not have advised ATC) will have morse identified it. If there is then a problem with the ILS during his approach there will be no way of the ATC advising the pilot of this fact if they (the ATC) are unaware that the pilot is using the ILS.

If the ILS gets switched off he's going to get flags up pretty smartish - he will be left in no doubt that the ILS had gone off, ident or no ident.

[Denti]

As for the opposite direction stuff, well fine for VOR or NDB, but the LOC signals would interfere with one another, so they are interlocked out so only one end can transmit at once.


Just a minor point here, yes, they can transmit both at once, at least over here in germany. Often enough there is a relevant remark on the ATIS that the opposite ILS is transmitting and therefore automatic landings are not allowed. Thats the only restriction though, normal approaches can be done.

Reason seems to be that each ILS (LOC and GS) needs to transmit a certain amount of time per month/quarter to retain its CAT III status. In the case of low visibility procedures becoming active the opposite will be of course switched off to allow automatic landings.

[tori chelli]

Pprune Radar

I wasn't sure whether to refer to CAA or NATS engineering...either way it's a specious point because I'm talking about en-route navaids notified H24 that also happen to have airfield approach procedures attached to them; irrespective of whoever operates them :hmm:

Can't fly IFR/IMC without a clearance? What if I get airborne from my (lit) strip at night in VMC (& IFR), fly into IMC while terrain safe and then fly the procedure out-of-hours to MDA, go-around back to MSA and fly back into VMC?

I'm looking at Benbecula, Biggin, Cranfield, Ronaldsway, Southampton (couldn't get Sumburgh to come up on the AIP site:ugh:) & Wick...what would anyone out there think if a pilot shot the published approach out of your hours using the en-route navaid? :hmm:

Tori

[Scott Voigt]

PPRUNE Radar;

You are indeed correct in your inference to the US way of doing it. Now, if you are IFR it doesn't matter if you are VMC or IMC, you are still IFR and need some sort of a clearance, BUT, if you are VMC and not in class B, you can just cancel IFR if you aren't getting what you want <G>, and go on your merry way.

Sorry it took me a bit to respond. But we have the green and white flag with the red dragon in the middle flying from the house right now and are entertaining guests at the moment from that far away land <G>.

Take care

Scott