Approach ban

[TenAndie]

never flown in middle east so couldnt say. do they not have their own rules in the middle east for approach bans ???

[NoJoke]

Ten

Some do, some don't because they don't operate to under the same regulatory authority. For example a mate of mine is an Australian, apparently over there the approach ban does not exist in the same way.

What actually happened was that the Vis was good, and indeed the 'reported' Vis 'improved' after landing. I would rather discuss than argue.

Now a general question to all. I am trying to find out if there is a definition of 'reported visibility' in context of a visual approach. For example when talking about Wind the book states 'Tower reported wind'. So could 'reported visibility' be defined as vis reported by anyone? For example, if a 'remote' Met office give a vis and yet the tower ask a departing aircraft to give a Vis report, does that count?

[Checkboard]

There have been several comments about the reason for the imposition of an approach ban:

This requirement was introduced to prevent the situation t)hat can exist with shallow fog whereby the runway is visable quite some way out but becomes obscured very close to the ground. (slant visual range ) This situation is quite common in europe.

and,

My impression was that the approach ban was introduced specifically to take the decision-making out of the cockpit -- and assessing visibility with any sort of precision from the cockpit is almost impossible.

The terrain clearance allowance for the missed approach is just 100'. if aricraft were to commonly fly the missed approach from the minima this simply wouldn't be a safe separation, and minimas would have to be significantly raised as a consequence. The reason the allowance is allowed to be so slim is that a missed approach from the minima is considered to be a statistically rare event, and the approach ban is there to ensure this - that is, you may not fly to such a low minima if there is an expectation that you will need to conduct a missed approach from that minima.

Once you meet the visual criteria specified iat JAR-OPS 1.430 then the approach ban criteria becomes irrelevant. Although it isn't specified for landing, JAR-OPS 1.430 allows the commander to determine the RVR/Visibility for take-off, even if the reported visibility is below the take-off minima [ para (a) (1) (iii) ] and of course it is implied that the Commander must verify the visual refernce (including visibility) from the cockpit on all approaches.

I would say that, given this, a commander's assesment of the visibilty for the approach certainly supercedes that of an ATIS, a tower assesment of visibility or even an RVR. Consider the case where an ATIS reports a visibility below the minima, however you commence the approach. The tower then reports a visibilityis above the minima so you continue past the approach ban point (you still don't have the required visual reference at this point, so you use the best information available - and you consider in this case the Tower report supercedes the ATIS). Past the approach ban point the Tower then reports an RVR below the limit, however you legally and safely continue, and at the minima make the required reference (including visibility) and land. All completely legal and safe as your assesment of the visibility at the minima is the only one that matters, not the reported RVR.

In the same sense, your assesment of the visibility when you became visual supercedes the ATIS, and you may contiue using the best information available.

[NoJoke]

Checkboard

Thanks for joining the confab. I don't have JAR-OPS docs available, so while we are JAR-OPS compliant we are not JAR OPS approved, hence certain convenient differences I think. You couldn't cut and paste 1.430 for me could you, or is there a web location I could look up. I would appreciate your help.

NJ

[Checkboard]

JAR-OPS are online at http://www.jaat.eu/publications/section1.html

You are right that in Australia there is no approach ban. There is also a comment in the Australian AIP to the effect that a pilot in command is an approved meteorological observer for the pupose of their own flight.

I fly in the UK now, and spent yesterday on the plane having a look for an equivalent statement here, but no joy I'm afraid.

As a defense for you, I would say that you did have a report of visibility before passing the outer marker - that report being your own observation.

[bookworm]

The terrain clearance allowance for the missed approach is just 100'. if aricraft were to commonly fly the missed approach from the minima this simply wouldn't be a safe separation, and minimas would have to be significantly raised as a consequence. The reason the allowance is allowed to be so slim is that a missed approach from the minima is considered to be a statistically rare event, and the approach ban is there to ensure this - that is, you may not fly to such a low minima if there is an expectation that you will need to conduct a missed approach from that minima.

It's an interesting argument, Checkboard, but I'm not convinced. I'm entitled to fly (repeatedly if I choose) an approach with a low ceiling and therefore a high expectation of a missed approach from it. And missed approaches are carried out routinely in training. I believe IAPs are designed to provide adequate separation from terrain or obstacles, where "adequate" does not include such a mitigation factor for the probability that a missed approach will actually be flown.

I would say that, given this, a commander's assesment of the visibilty for the approach certainly supercedes that of an ATIS, a tower assesment of visibility or even an RVR.

The word visibility comes up frequently in regulations. In almost all other cases, flight visibility is the phrase used. This is clearly defined as being the forward visibility as assessed from the flight deck. The approach ban refers to reported RVR/Visibility. If the commander's assessment of visibility were to supersede the reported value, why do you think the regulations are so explicit in using the word reported?

[rak64]

the e)

(e) The approach may be continued below DA/H or MDA/H and the landing may be completed provided that the required visual reference is established at the DA/H or MDA/H and is maintained.

I think the term "at the DA/H or MDA/H" make it unclearly, every approach may be continued if a element of the approach light .... are in sight. Isn't it fully legale to count on that, to continue in that case just before the "approach ban point"?
Next, the word visual is relly pluryvalent, so the sheeps on the green can use the meaning that makes your guilty. Say on radio what you see, it sounds silly but it is clearly.
Talk with the controller before, the weather might not be equal at all directions, perhaps against the sun, or due to smoking hills, use the best suitable RWY. If you are sure to met a safe approach, make a statment after the landing.

[bookworm]

I think you have to read (e) in the context of (a) and (c) as well.

JAR-OPS1 seems to consider the approach as three parts:

Part 1 before outer marker
Part 2 between the OM and the DH
Part 3 after the DH

It seems pretty clear to me that (e) is intended to govern the decision to continue the approach from 2 to 3, while (a) is intended to govern the decision to continue the approach from 1 to 2. However, because, unlike the UK legislation, (e) is drafted in the positive ("may be continued if"), you might have enough of a drafting loophole to get off the hook. I wouldn't want to be the one putting your case though.

If you're a UK operator, or operating in the UK, the ANO offers no such loophole.

[keithl]

I'm still following this with interest. Can we please get rid of the "shallow fog" red herring (sorry- that's "irrelevance" for those who don't have colloquial English). You are just as likely to encounter shallow fog if the visibility deteriorates after the AB point - in which case you are legal to continue to minima. So the AB doesn't seem to have been established to avoid that one.

I think it will be much more profitable to pursue NJ's question "What is 'reported visibility' ?"

[goinggrey]

JAR-OPS 1 Rules are there to protect you
let me say that again !
JAR-OPS 1 Rules are there to protect you
to keep you safe in a long career so you can grow up with your grand children
not to lick your employers ass when the weather is ****
Read the Rules and obey and you will live to grow up with your grand children
Next time - Simple !

[Checkboard]

bookworm (and interested others), my comments are not my own musings!

The information originally came from an article written for the Australian CAA's safety magazine by their chief airways surveyor, the (late) Captain John Edwards. (Aviation Safety Digest, issue 139, "ILS - Some whats and whys", if anyone wants to look it up) Here is the relevant quote:

... CAR 257 prohibits a pilot continuing an approach 'when any element constituting the meteorological minima for landing is less that that determined for that aerodrome except in the case of an emergency'. This CAR prevents a pilot preceeding to the minima to 'look and see' if he can land. This seemingly conservative restriction recognises that the missed approach is not designed with protection that permits its use as a normal event (as distinct from the comparatively infrequent use it should get from operations conducted in accordance with the CAR). In the case of the precision segment of an ILS the segment is designed with the following safety objectives:

(a) Overall risk of collision with obstacles
1 X 10exp(-7) (18)
(b) Missed approach rate
1 X 10exp(-2) (19)

The CAR recognises the above and is intended to ensure that pilots of aircraft which are permitted to proceed to the minima enjoy a high probability of being able to land off the approach. (NATO: International assessment has been that the criteria necessary to protect the missed approach risk equal to the normal event, most likely would incur significant operational penalty.).

18. ICAO Doc 8168-OPS/611, Vol 2 para 21.1.4
19. ICAO Coc 8168-OPS/611, Vol 2, para 21.4.8.8.3.2
ICAO Doc 9274-AN/904, Part 2, para 7.3.1

I didn't include the references before as I was quoting from memory. The Australian context shouldn't matter, as approaches are designed to ICAO criteria.

The approach ban refers to reported RVR/Visibility. If the commander's assessment of visibility were to supersede the reported value, why do you think the regulations are so explicit in using the word reported?

Simply because the assumption was that an aircraft using this rule is conducting an instrument approach, and as such (i.e. not being visual) would have to rely on a report. As to a commanders observation superceeding an RVR report, JAR-OPS 1.405 specifically says:

(c) If, after passing the outer marker or equivalent position in accordance with (a) above, the reported RVR/visibility falls below the applicable minimum, the approach may be continued to DA/H or MDA/H."

This paragraph would have no meaning unless the commanders observations at the minima entitled them to land.

[NoJoke]

Visual

So my point is. I called Visual before the approach ban point. Tower then cleared me for the approach (then a visual approach) although tacit, it was still a clearance. Y/N. My assessment of the Vis was higher than the ATIS Vis.

[bookworm]

Checkboard

I'm grateful for the references. I don't have access to Doc 9274 as cited. In case it's helpful, here's the bit in PANS-OPS Vol II:

To allow for the fact that only a proportion of the approaches results in a missed approach, the computed risk of each obstacle in the missed approach region was factored by a missed approach rate. Taking account of the variability in missed approach rate experienced over different periods of time and at different locations, one per cent was deemed to be representative of the general order of missed approach rates likely to be experienced and was used in the CRM.

So I've learned something new. But I'm still not convinced on this being the motivation for the approach ban.

I'm puzzled by what Edwards writes (in your quote).

CAR 257 prohibits a pilot continuing an approach 'when any element constituting the meteorological minima for landing is less that that determined for that aerodrome except in the case of an emergency'. This CAR prevents a pilot preceeding to the minima to 'look and see' if he can land.

Here's what CAR 257 actually says (my bold):

(4) If an element of the meteorological minima for the landing of an aircraft at an aerodrome is less than that determined for the aircraft operation at the aerodrome, the aircraft must not land at that aerodrome.

(6) This regulation does not prevent a pilot from:
(a) making an approach for the purpose of landing at an aerodrome;
or
(b) continuing to fly towards an aerodrome of intended landing specified in the flight plan;
if the pilot believes, on reasonable grounds, that the meteorological minima determined for that aerodrome will be at, or above, the meteorological minima determined for the aerodrome at the time of arrival at that aerodrome.

and from CAR 2

aerodrome meteorological minima means the minimum heights of cloud base and minimum values of visibility which are determined in pursuance of regulation 257 for the purpose of determining whether an aerodrome may be used for take-off or landing.

So first of all, this regulation is different from the JAR-OPS1 and ANO approach ban in at least three ways:

* contrary to what Edwards says, there's apparently no ban on the approach as such, but rather on landing

* the minima include the cloud-base criterion

* there's no differentiation between reported conditions and the conditions the pilot finds

Even if we accept that missed approaches are not protected to the same level of safety as the rest of the approach, a regulation aimed at addressing this would surely

a) ban approaches with the ceiling below minima (as CAR 257 bans landings)

b) ban repeated (e.g. training) approaches in which the missed approach is to be flown in IMC, even if the vis/RVR is above minimum

wouldn't it?

[JAR-OPS 1.405(c)] would have no meaning unless the commanders observations at the minima entitled them to land.

But the crew's acquisition of visual reference at DH does entitle them to land. That's the whole point of the paragraph. The crew does not have to make a judgment as to the RVR/vis in relation to minima. Once the OM (or 1000 ft point) is passed, the only criterion that remains is the crew's acquisition of visual reference. But the crew's acquisition of visual reference does not exempt them from 1.405(a) requiring them to break off the approach at the OM if the reported RVR/vis is below the minimum.

[bookworm]

I also add the following, which I think indicates even more strongly that the reported RVR/vis of JAR 1.405(a) is not replaceable by a pilot assessment.

Appendix 1 to JAR-OPS 1.430 (a) Take-off Minima

(1) General
(iii) When the reported meteorological visibility is below that required for take-off and RVR is not reported, a take-off may only be commenced if the commander can determine that the RVR/visibility along the take-off runway is equal to or better than the required minimum.

(iv) When no reported meteorological visibility or RVR is available, a take-off may only be commenced if the commander can determine that the RVR/visibility along the take-off runway is equal to or better than the required minimum.

Table 1 Note 3: The reported RVR/Visibility value representative of the initial part of the take-off run can be replaced by pilot assessment.

Table 2 Note 2: The reported RVR/Visibility value representative of the initial part of the take-off run can be replaced by pilot assessment.

(3) Required RVR/Visibility (iii) When reported RVR, or aids meteorological visibility is not available, the commander shall not commence take-off unless he can determine that the actual conditions satisfy the applicable take-off minima.

These are 5 paragraphs in which JAR-OPS1 makes it explicit that a pilot assessment of RVR can replace the reported value. All relate to take-off only. There is no corresponding note or exemption for approaches (subparas b,c,d,e,f). Surely you would expect such a note or exemption if it were permitted for approaches.

(Edited to add that I see Checkboard noted the same difference between a and b,c,d,e,f in a previous post and drew the opposite conclusion!)

[rak64]

From JAR-OPS 1 1.430: A pilot may not continue an approach below MDA/MDH unless at least one ....... visual references for the intended runway is distinctly visible and identifiable to the pilot.

That means: it is allowed to continue an approach with the visual reference below, at, even above the MDA/MDH.
If the pilot maintaining visual references for the intended runway, before the OM/EP (Equivalent Position), than the approach ban is not valid.
I'm right with this?? (Hopefully nobody reminds me my former position with MC Donald )

[Checkboard]

The Edwards article is about 19 years old now - hence the difference in the CARs quoted I copied it for reference at the time, but haven't flown in Australia for years now. I included it here to illustrate the thinking of an airways surveyor (the extrapolation to the UK/JAR OPS approach ban was my own) in the same way that I included the JAR take-off references to illustrate the principle that a Commander's observation is just as valid as an RVR (and more current, as it happens in real time).

As it applies to an ILS, the cloud base is of little importance, as the visibility is what will determine whether or not you will see far enough along the approach path to make the required visual reference.

[DFC]

rak64,

Don't have the docs to hand but if I remember correctly, if you place the DA/MDA above the height at which the approach ban would apply then you also have to increase the approach ban height.

In other words, you can never have a situation where the DA / MDA is at a higher level than the approach ban Altitude. Thus you will never get to see the DA/MDA altitude unless you can meet the requirements for the approach ban.

Regards,

DFC

[NoJoke]

Oh my

DFC. I understand your point of view, and due to the extensive discussion we all have had; I think I understand the Regs. However I still ask that if cleared for the approach by ATC AFTER declaring visual, does that not indicate that the visual approach is approved? In reality ATC knew the situation and it was an understanding that both parties had. I was visual ....... over 9 km

[keithl]

So, what is a "Visual Approach"?

This from the UK Manual of Air Traffic Services Glossary:

Visual Approach An approach by an IFR flight when part or all of an instrument approach procedure is not completed and the approach is executed with visual reference to terrain.

In your case, NJ, (although not in UK, I know) you were IFR and part of the instrument approach was not completed (due to the Approach Ban plus being visual). You executed the approach with visual reference to terrain.

If ATC were happy with that, and it seems they were, then only some more limiting company rules could put you in the wrong, it seems to me. As to a specific "cleared visual approach" statement from ATC, I'd say that was implied from what you have told us.

An Approach Ban, of course, can only prevent an Instrument Approach.

[rak64]

Still some mix of visual with visual reference.
visual means visual approach, what was here described correctly.
But noyoke reported visual by meaning visually identified the elements and/or the active RWY.

The intention of the approach ban, to improve the level of safety by implementing a rule, not allowing a senseless approach, is fully okay. Ask yourself, if the active RWY could visually identified before the OM/EP, what is the visibility?! The aim was to find some clinical criteria, but it end by general threat pilots as not reliable. Normally civil aviation is based of thrust, the approach ban is introducing a new view.