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B737-800W
11th Mar 2011, 21:27
Hello there,

Regarding Approach Ban, is there a difference on holding approach from a straight in approach?

Tnx

FlightPathOBN
11th Mar 2011, 21:40
Could you explain this more please?

eckhard
11th Mar 2011, 23:32
If I understand you correctly B737-800W, you are asking if the same 'approach ban' criteria apply to:

an approach which is started from a holding pattern; and

a straight-in approach.

The answer has to be, 'yes'.

I hope I haven't missed something!

Eck

Jinkster
12th Mar 2011, 11:09
I guess you wouldn't leave the hold without the minima being correct or above.

Not sure how this stands legally but it makes sense.

Will go look in a book.....

Microburst2002
12th Mar 2011, 13:03
I don't think so.

de facto
12th Mar 2011, 13:37
An approach ban is an altitude at which if the visibility is below the crew/aircraft minima, the pilots must initiate a missed approach.
Some ATC will request your minima before they clear for the approach and will provide you with the actual RVR at the 1000ft/OM.(non-precision/precision).
As a pilot you can request the info too.
But again some play by the rules and some don't.
Seen/heard scary things over the years...

Wizofoz
12th Mar 2011, 14:17
Does the approach ban have any sense in CAT IIIB no DH approaches?

--------------------------------------------------------------------------------
I don't think so.

Cat IIIB still has a minimum RVR value- I the reported RVR falls below this before the ABP, the approach cannot be continued.

The Real Pink Baron
12th Mar 2011, 15:02
Most airports in the world you can fly the approach, and it is your decision at what stage (not below published min) you decide to scrub it. Some airports (Dhaka) (Local rules) will not allow you to attempt an approach!
Check the AIP.
Be safe, Alex

PT6Driver
12th Mar 2011, 15:35
It does not matter how you get onto the final approach (radar vector, procedure or holding then procedure etc.) the approach ban is still there. (This assumes the country you are operating in and or the company you work for recognise this 'ban').
As JAR and EASA have the approach ban point as the outer marker, equivilant point or 1000' aal then all holding will be above this altitude or certainly further out on the approach path.
You will therefore have a distance to travel along the final approach path prior to the approach ban point for all instrument approaches.

HEATHROW DIRECTOR
12th Mar 2011, 15:46
At Heathrow even if nothing was holding but an inbound provided his minima which was below limits we would instruct him to join the hold..

Microburst2002
12th Mar 2011, 18:28
Wizofoz

In a CAT I, CAT II, CAT IIIA and CATIIIB-with-DH approaches, after we overfly the OM we are allowed continue the approach even if reported RVR gets below minimum. But we can only continue till the DH, at which we go around unless we have the required visual references.

what if there is no DH at all?

In CAT IIIB-with-no-DH there is no DH, only AH. There is nothing to decide, no point at which we have to see any visual references. So I guess we should overshoot as soon as the RVR goes below minimum, at any moment during approach. Or maybe revert to CAT IIIB-with-DH minimum and then decide at that DH, It occurs to me now.

9.G
12th Mar 2011, 19:03
For Category II operations the TDZ measurement is required, and for Category III operations the TDZ and MID measurements are mandatory. For CAT III without DH EU-OPS 1 requires only one RVR measuring point on the runway. FAA requires all 3 RVR readings to be available and above minimum. Approach ban Policy regarding an approach ban may differ from country to country. Usually the final approach segment may not be continued beyond the OM or equivalent DME distance if the reported RVR is below the published minima for the required transmissometers. After OM or equivalent position, if RVR becomes lower than the minima, the approach may be continued. FAA certified operators usually have OPS specs with FAF being nominated as approach ban point. Some countries set the approach ban at IAF. :ok:

Daysleeper
12th Mar 2011, 19:07
In a CAT I, CAT II, CAT IIIA and CATIIIB-with-DH approaches, after we overfly the OM we are allowed continue the approach even if reported RVR gets below minimum. But we can only continue till the DH, at which we go around unless we have the required visual references.

what if there is no DH at all?

In CAT IIIB-with-no-DH there is no DH, only AH. There is nothing to decide, no point at which we have to see any visual references. So I guess we should overshoot as soon as the RVR goes below minimum, at any moment during approach. Or maybe revert to CAT IIIB-with-DH minimum and then decide at that DH, It occurs to me now.

What?

Nooooooo

Right , you have to have the required RVR at the approach ban point, (Outer marker or equivalent normally check your company SOP) after that you can if you wish continue with the approach to your appropriate minima. A Cat3b No DH approach means you can continue through to the ground... the clue is in the no decision height bit.

Denti
12th Mar 2011, 19:54
Guess it depends on your local regulator. Ours required that we have to discontinue the approach at any point of the approach if the RVR drops below the CAT IIIb required RVR (75m for the 737). Same justification as Microburst posted.

Wizofoz
13th Mar 2011, 05:31
Wizofoz

In a CAT I, CAT II, CAT IIIA and CATIIIB-with-DH approaches, after we overfly the OM we are allowed continue the approach even if reported RVR gets below minimum. But we can only continue till the DH, at which we go around unless we have the required visual references.

what if there is no DH at all?

In CAT IIIB-with-no-DH there is no DH, only AH. There is nothing to decide, no point at which we have to see any visual references. So I guess we should overshoot as soon as the RVR goes below minimum, at any moment during approach. Or maybe revert to CAT IIIB-with-DH minimum and then decide at that DH, It occurs to me now.

Day-sleeper is correct. I don't know how you came to understand the rules as above.

Firstly, ABP is not always (or even usually) the OM.

If sufficient RVR (absolute minimum for Cat IIIB is 75m) is reported at ABP- continue approach

If sufficient RVR is NOT available at ABP, go around.

After ABP- continue- and yes, for a Cat IIIB that means continue to touch down, with no requirement to establish a visual reference.

Is that clearer?

Microburst2002
13th Mar 2011, 06:58
So as I said, aproach ban has no sense in a CAT IIIB noDH approach!

Denti, thanks.
What is your local regulator?

Daysleeper

so in a CAT IIIB no DH approach I can continue if RVR becomes 0/0/0 if I have already passed the approach ban height (say 1,400 AGL)? Noooo, I don't think so.

Topper80
13th Mar 2011, 09:10
Microburst 2002:

so in a CAT IIIB no DH approach I can continue if RVR becomes 0/0/0 if I have already passed the approach ban height (say 1,400 AGL)? Noooo, I don't think so.

Yes, it is correct: the regulation (Eu-ops) just changed. In the New version, no more required to go around in CAT IIIB no DH if RVR goes below 75....

9.G
13th Mar 2011, 09:21
Microburst2002, it all depends on the OPS specs and country regs you're flying to. Under EU OPS one can commence the approach regardless of reported RVR and may not continue beyond ABP if it falls below the required one. For CAT IIIb you only require single RVR anywhere along the RWY of 75 m, that's all. Once you passed ABP RVR is of no relevance any more it's a simple reliance on sophisticated automation therefore the AH. It's a different ball game with FAA folks once again their specs stipulate all three RVR to be above and available to commence CAT III b approach however once passed the ABP the approach can be continued regardless of RVR as under EU OPS as well. Approach ban policies vary with countries thus make sure to check the applicable regs. :ok:

Denti
13th Mar 2011, 09:55
@microburst, LBA or german CAA of course operating under EU-OPS. We are required to have at least 75m RVR for CAT IIIb on the 737 during the whole approach, no approach ban so no difference if before or after a certain point. Those 75m have to be met for all points covering the required landing distance (computed to dispatch criteria). Even on our non fail operational 737 those 75m are now a hard go-around criteria during all parts of the approach, however after the ABP we can continue if the RVR falls below the CAT III value but still is 75m or greater.

Nightstop
13th Mar 2011, 10:32
Our ABP is now 1000' aal for all types of approaches. No messing around with OM, equivalent position etc anymore. Makes it easier :ok:

9.G
13th Mar 2011, 11:33
Denti, it's got nothing to do with LBA but with your specs. If you're fail passive on 737 or no auto roll out system installed then all 3 RVRs are mandatory at any point and there's no approach ban coz it's about you being able to perform a manual roll out. Airbus however is fail operational therefore it's a matter of reliability of automation only consequently approach ban applies. 75 meters are only there to be able to taxi that's it. :ok:

Denti
13th Mar 2011, 12:56
Actually, the 737 of course has auto rollout and a fail operational system, we also have airbus fleets and the restriction above apply to all of them (OM A restriction). Without it we wouldn't get our AOC, so it is enforced by the LBA.

9.G
13th Mar 2011, 14:10
I hear you Denti, you gotta follow whatever your manual says. However that's not the EU OPS valid concept but your OPS specs imposed by your authority for some reasons. We are talking about EU OPS approach ban concept here and it's applicable to any approach including CAT III b. :ok:

Microburst2002
13th Mar 2011, 14:48
Can any of you guys put a link to the EUOPS where this issue is laid down?

And (this is to the veterans) Does anyone know the history of the approach ban concept?

I would say the approach ban concept is avoiding the danger that means airplanes flying approaches with very low probability of success and a not so low probability of "temptation to fly just a little bit below minimum". If the event that RVR goes below minima after a given point in final, then you can wait till the DH to discontinue the approach.

With no DH, if you can only continue and land, even in zero zero RVR. Why don't they just establish CAT IIIC?

Besides, if you land with nearly zero RVR, you will have to wait in the runway centerline until RVR increases. No one else can shoot that approach after you, in the mean time.

Torque2
13th Mar 2011, 15:25
Direct extract from the section EU Ops:


OPS 1.405
Commencement and continuation of approach
(a) The commander or the pilot to whom conduct of the flight has been delegat ed may commence an instrument approach regardless of the reported RVR/Visibility but the approach shall not be continued beyond the outer marker, or equivalent position, if the reported RVR/visibility is less than the applicable minima.
(b) Where RVR is not available, RVR values may be derived by converting the r eported visibility in accordance with Appendix 1 t o O PS 1.430, subparagraph (h).
(c) If, after passing the outer marker or equivalent position in accordanc e with (a) above, the reported RVR/visibility falls below the applicable minimum, the approach may b e continued to DA/H or MDA/ H.
(d) Where no outer marker or equivalent position exists, the commander or t he pilot to whom conduct of the flight has been delegated shall make the decision to continue or abandon the approach before descending below 1 000 ft above the aerodrome o n the final approach segment. If the MDA/H is at or above 1 000 ft above the aerodrome, the operator shall establish a height, for each approach procedure, below which the app roach shall not be continued if RVR/visibility is less than applicable minima.
(e) The approach may b e continued below DA/H or MDA/H and the landing may b e c ompleted provided that the required visual reference is established at the DA/H or MDA/H and is maintained.
(f) The touch-down zone RVR is always controlling. If reported and relevan t, the mid point and stop end RVR are also controlling. The minimum RVR value for the mid-point is 125 m o r the RVR requ ired for the touch-down zone if less, and 75 m for the stop-end. For aeroplanes equipped with a roll-out guidance or control system, the minimum RVR value for the mid-point is 75 m.
Note: ‘Relevant’, in this context, means t hat p art of the runway used during t he h igh speed phase of the landing d own to a s peed of approximately 60 knots.

9.G
13th Mar 2011, 16:57
torque2 nailed it.

Kijangnim, no idea why you're shocked since FAA has got exactly the same procedure in place. The only difference is that to commence the approach PIC needs 3 RVR equal to 75 m. Once FAF has been passed it's a go as well regardless of the reported RVR. :ok:

Denti
13th Mar 2011, 17:41
(c) If, after passing the outer marker or equivalent position in accordanc e with (a) above, the reported RVR/visibility falls below the applicable minimum, the approach may be continued to DA/H or MDA/ H.


This is the problem though, at least with the LBA and CAT IIIb with no decision height. As there is no decision height you may not continue, if there is one, you may as it gives time for a go/no-go decision. Especially in consideration of point e).

Point f) is seen as a fixed requirement of 3 (or 4 if you have two midsection readings like MUC for example) RVR readings of at least 75m if they are relevant, ie as long as they are within the landing distance required which of course has to be calculated before starting the approach. If you have no automatic rollout system (older 737s for example) you need even higher readings.

Wizofoz
13th Mar 2011, 18:14
This is the problem though, at least with the LBA and CAT IIIb with no decision height. As there is no decision height you may not continue, if there is one, you may as it gives time for a go/no-go decision. Especially in consideration of point e).



Perhaps under your regs.

Under the ones I operate to, you can continue.

Microburst2002
13th Mar 2011, 18:16
Thanks Torque

If follows that the approach ban is necessarily associated to a DH (or MDA in NPAs).

NoDH means No Approach Ban point.

If there is no DH you cannot use the approach ban point as a "cleared for anything you want beyond here" point. That would go against safety, I think.

Anyhow, when are they going to invent some fog goggles or something so we can just land normally no matter what is whe visibility? Don't the military guys have something like that yet? all this AWO is quite complicated.

Also it would be nice to have those x-ray vision glasses that you can use to see women underwear, but that is another story :O

9.G
13th Mar 2011, 18:33
Denti, may I suggest you re-read your manual carefully again. It's plain simple, for CAT III A&B with DH approach two RVR reading are mandatory TDZ & MID. In case auto roll out is performed MID RVR can be 75 m whereas TDZ must be 200 m in order to acquire visual cues for CAT III A 3 lights and for CAT III B 1 light. CAT III B with NO DH no need to see anything thus only TDZ RVR 75 is required which can be substituted by MID, rollout RVR has NO effect whatsoever. Have a look at the table 6a for failed or downgraded equipment for AWO. EU OPS.

For CAT IIIB operations with no DH, an operator shall ensure that, for aeroplanes authorised to conduct no DH operations with the lowest RVR limitations, the following applies in addition to the content of Table 6a:

RVR At least one RVR value must be available at the aerodrome.:ok:

P.S. once again the thread is about the approach BAN it's applicable as per country's regulation and OPS specs of the operator. EU OPS approach ban is applicable to any approach.:ok:

Torque2
13th Mar 2011, 18:36
Micro you are allowed to continue provided the rvr is greater than 75, beyond that point you can continue to the DH aand NoDH is valid. Provided the aircraft does not downgrade the landing category all is valid.

In Canada, for example, the requirement is to discontinue the approach if the rvr goes below minima even after the ABP, not so in EASA land.

The airport has to be equipped to Cat IIIB standard for No DH, as far as I am aware there are none in Canada and a very few in the US (Seattle being one of course, reqd for Boeing testing and certification I believe but stand to be corrected.)

There is no interpretation required, those are the rules as certified if you operate under EASA. :ok:

Microburst2002
14th Mar 2011, 09:13
(c) If, after passing the outer marker or equivalent position in accordanc e with (a) above, the reported RVR/visibility falls below the applicable minimum, the approach may b e continued to DA/H or MDA/ H.

It's written. Maybe continued to DA/H. If there is no DH, the approach ban has no sense. Or its sense is like James Bonds and other double zero: a license to kill.

Wizofoz
14th Mar 2011, 09:29
How is allowing the aircrat to Autoland a license to kill? the required vis in CatIIIB is only there for turn-off, taxi anyway.

I'm sorry if you don't like the Regs- We're just telling you what they are.

Microburst2002
14th Mar 2011, 18:49
agree I exagerate

but if there is no DH you cannot continue to DH in the hope that REQUIRED rvr is attained. So the approach ban cant be applied.

the text says clearly that you may continue to DH. No mention of the no DH case. In other countries they make it very clear that. In EUOPs is not so clear.

It all comes to this question

"can you land with rvr 0/0/0, knowing that that is the rvr?"

if answer is affirm: why the 75m requirement?

if taxi and fire brigade are the reasons: Why do you disregard those reasons after passing the approach ban?

Wizofoz
14th Mar 2011, 22:50
Microburst,

That's the same as saying, "If, after you pass the ABP, the reported vis goes below the minimum, can you land if you have visual reference at the DH" The answer is of course, yes you can.

In the same way, if the vis goes below minimum after ABP on a CatIIIb, you can land.

There are minimum RVR values, and then minimum visual reference criteria for each catagory of approach, except CatIIIb which basically has no visual reference criteria, you just let it land!!

Microburst2002
15th Mar 2011, 09:46
I see your point, but i am afraid I still think that it is not right to land in a runway with less than the required RVR, even if there are no visual cues required to land and the AFS can do it very well in zero visibility.

The 75 meters are required for a reason, and I think that this reason is still valid after the approach ban. And so they think in other regulations, it seems.

I am too stubborn, sometimes, I know

Anyway, I will probably retire without ever having had this case. And without having enjoyed the x-ray underwear scanning glasses:}

9.G
15th Mar 2011, 09:57
M2002, all other regulations except Canucks have implemented APB. It's the whole purpose of a ABP to give the PIC the chance to assess the dynamic of the situation. The idea of a AB is that an approach can be started regardless of WX, approaching the ABP a go around must be performed in case there isn't a improvement. Once beyond however it's a matter of getting to see at MDA/DA whether a landing can or can't be accomplished safely. ON CAT III B there's nothing to see anyways thus it becomes a redundancy matter. Speculations about emergencies in LVO, might bear grounds as much as the odds of probability. Ask yourself a question would you rather land having an engine fire on CAT IIIB on short final on go around? I think you know the answer.:ok:

CoiledString
30th Mar 2011, 15:32
Read EU OPS1 Subpart E 1.405
Commencement and continuation of approach
(a) The commander or the pilot to whom conduct of the flight has been delegated may commence an instrument approach
regardless of the reported RVR/Visibility but the approach shall not be continued beyond the outer marker, or equivalent position, if the reported RVR/visibility is less than the applicable minima.