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Oliver James
20th Feb 2002, 17:01
I have been hearing that BA do not train to Cat 3A approach limits, because of costs?; they do Cat 2 or Cat 3B. Would anybody in BA care to confirm or comment on this please?

Last week a BA Long haul aircraft refused 27L, which is Cat3A at the moment, and insisted on 09L which, as I write, is the only Cat 3B ILS that Heathrow has. I am told this added significantly to the early morning problems because effectively it caused 2 runway changes; from West to East and then back again. As a result, it probably won't be allowed to happen a second time. (Hearsay)

When I made enquiries about it I was given the above information about BA's approach Cat. training. Is Cat 3A a manual landing from a 50' DH or is it an autoland from a 50'DH? I was told the former but that hadn't been my understanding.

Why weren't other BA aircraft affected?

Discuss...

Captain Airclues
20th Feb 2002, 17:46
120.4

BA train for all categories both in initial conversion, and recurrent training. It costs no more to train for a Cat 3A approach as for a Cat 3B approach.. .I can only speak for the 747-400, but we operate to 100m and No DH for Cat 3B, and 200m and 50ft DH for Cat 3A. I believe that the 777 has similar limits. Autolands are mandatory in RVRs of less than 550m.. .I find your story about the runway change hard to believe. For the aircraft to require a Cat 3B approach the RVR would have had to have been less than 200m. Could you please tell me which day this was, and were all the other aircraft getting in OK with this RVR?

Airclues

Positive Climb
20th Feb 2002, 17:49
120.4 - I think you have been 'led up the garden path' somewhat.

I can't quite work out why it would save costs to train to CAT 3B instead of 3A, but this is an incorrect statement.

I would only be guessing, but I imagine the captain of the said aircraft had good operational reasons why he needed CAT 3B on the day.

As for your second question, I cannot speak for all BA fleets, but on the 737 when required in LVP's, we fly CAT 3A approaches to an autoland wherever possible.

regards,

P.C.

(edited for ambiguity - thanks Beamer !!!)

[ 21 February 2002: Message edited by: Positive Climb ]</p>

beamer
20th Feb 2002, 17:53
Positive Climb

Only when weather conditions necessitate surely ?

Fat Tony
20th Feb 2002, 17:56
With due respect 120.4, you clearly have very little understanding of this topic!!! To ask whether CAT 3A is a manual landing or autoland (regardless of the DH) suggests to me that your facts may not be entirely correct.... .To answer your question in brief, we are trained to operate our a/c down to CAT 3B no DH (ie no call-outs, no visual requirement) where possible as this gives the greatest chance of a successful landing in low vis. This is dependent on a/c technical status, the airport in question and the air traffic procedures in force at the time of the approach.

In some cases the airport may only be certified by BA to be used for CAT 2 or CAT 1 approach minima: it depends on the airport facilities etc.

However, and I know someone will correct me if this is a fleet specific thing, on my a/c 757/767 we can certainly complete a landing to CAT 3A minima if that is the most appropriate available. Incidentally, although 3A minima tends to be 50R, it is not specifically that. ie- check the performance manual.

If only 2 autopilots are available then 3A is the lowest minima allowed. 767 can also do a planned 1 engine autoland; 757 can once approach has been started.

Hope that answers your question.

[ 20 February 2002: Message edited by: Fat Tony ]</p>

Oliver James
21st Feb 2002, 03:02
Thanks chaps.

First thing to say is, I found the information about the approach catagories difficult to believe myself as it was contrary to all the understanding I have gained from 20 years in ATC. I had always understood that autoland was mandatory in Cat 3 conditions. I dare not reveal my source, it would embarrass him and shock you.

Capt. Airclues, be in no doubt about the runway change. I am in a position both to see the relevant log and speak to the ATCOs who controlled it an hour or so before I relieved them. I checked again today, it happened! From the log, there were no go arounds, IRVRs not less than 300m. It was either Sunday or Monday morning, just before 06:00. I can check if you need to know.

Fat Tony: Thank you! My having asked the question I suppose I can understand your doubts, I am actually aware of the requirements for low. vis. ops. I asked it because I needed to be sure that it was duff gen. <img src="wink.gif" border="0">

Point 4

[ 20 February 2002: Message edited by: 120.4 ]</p>

Cough
21st Feb 2002, 03:16
120.4 - Just for clarification.

CAT III - AutoLand Mandatory. Limits described above but basically 50RA/200m (or 150m if you are an RJ100?) for CAT IIIa, less for 3b (A/C dependant)

CAT II - AutoLand Probable! On our 737 Fleet you can disconnect below DA (100'RA/300m) and manual land, but it is normal to autoland.

No different training for any of these.

Oliver James
21st Feb 2002, 03:46
Thanks Cough. All cleared up. It is going to be an interesting chat..... . . :) :)

[ 20 February 2002: Message edited by: 120.4 ]</p>

snooky
21st Feb 2002, 04:02
I can't be absolutely specific because I don't have the document in front of me, but I recall that recently there was some doubt about the use of 27L for cat 3 approaches because of a suspected bending of the localiser beam at a late stage of the approach.

Despite the runway recently being upgraded back to cat 3 after a period as a cat 1 runway, I recall a nubrief item saying that BA aircraft should continue to operate only to cat 1 minima on this particular runway until further investigation of the suspected bending had taken place.

This would perhaps explain the request for 9L in the original case in question.

Hand Solo
21st Feb 2002, 04:27
Quite right Snooky, all company aircraft to use Cat 2 DH on 27L due beam bends until further notice. Same brief also states that 09R and 27R are Cat 1. Perhaps if the aircraft was looking tight on fuel he may have requested the runway that gave him the best chance of getting in, rather than going around and having all sorts of troublesome fuel problems.

BIK - which UK airline is operating with HUDs?

[ 21 February 2002: Message edited by: Hand Solo ]</p>

411A
21st Feb 2002, 08:57
Maybe these BA flights should divert to AMS... :)

Oliver James
21st Feb 2002, 12:53
It seems there are some directives within BA that we are not aware of on the ground. That is a bit disappointing since you partially own us and it would assist our service provision to you if we knew of these things.

Snooky: I believe 27L was downgraded to Cat 2 not 1, but has been back to 3A for a while now. Would a directive to use Cat 2 limits not have affected all BA aircraft? The others were landing 27L okay.

Clearly the Captain did what he thought was best. My purpose here is to understand the decision so that should the circumstances arise again I will be better placed. As things stand, the mumbling here is why didn't he go to Gatwick?

Point 4

[ 21 February 2002: Message edited by: 120.4 ]</p>

snooky
21st Feb 2002, 14:11
120.4, I agree that the captain was merely doing what he thought was best.

There would be many other considerations which he would have to take into account which we are not party to. These would include the weather conditions at his diversion and the amount of fuel remaining.

I can see that theoretically 27L was above his cat 2 limits, but it does seem that a good policy would be (wind permitting) to use the runway with the lower limits as the main landing runway in order to avoid possible go arounds and diversions.

Is the noise lobby possibly the reason for not so doing?

It does seem strange to me that BA do not accept the promulgated classification of the runway.

Oliver James
21st Feb 2002, 19:04
Snooky:

It is strange that BA should not accept the promulgated runway without good reason, I agree and I would like to know if there was.

Incidentally, the IRVR at 09L touchdown was worse (as it nearly always is due the resevoirs) than 27L and that is why, having landed this a/c on 09L, ATC changed back to Westerlies. Also, as this aircraft is a LAM arrival, 09L added some 30 miles to his intermediate approach.

Your point about the lower limit runway is valid but we don't get involved in the noise issue, except for attempting CDAs (near impossible if you want a good landing rate on both runways!).

The "correct" landing runway is predetermined according to a strict rotation. Towards the end of the night shift Tower tell us which is the correct landing runway and, wx permitting, we use it. (The use of the other runway for landing is dependant on us having 10 minutes delay between 06:00 and 06:30 and 5 minutes delay between 06:30 and 07:00.)

Point 4