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New landing distance calculations for Airbus

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Old 14th Oct 2012, 23:52
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New landing distance calculations for Airbus

Anyone have anything good to say about the new method of calculating landing distances required in flight on Airbus types?
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Old 15th Oct 2012, 01:55
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The method is actually quite logical from my point of view but are you aware (just checking) that it's now a mandatory calculation prior to each approach and landing?

My opinion? It seems completely pointless to have to produce a 3 or 4 digit number that 99.9% of the time will be above the LDA figure for any particular runway my current airline operates into. Our CP is trying to avoid having us do the calculations for EVERY landing but I hear several others want to incorporate the procedure (like pretty much everything else related to paper here, it'll get delegated to the FO for every approach anyway, so why not! ). We operate in the worst possible environment in terms of ATC (constant ATC chatter, unnecessary vectoring, step climbs and descents even on short sectors) and changing runways / weather.

My thinking is what's wrong with having Flight Ops produce some worst case LDR tables for all our destinations? The 'Landing performance' procedure can simply be a confirmation that even with the worse kind of weather and braking action we will be able to stop with Autobrake Med. Anything better than this is a therefore a bonus.

Anyone else?

Last edited by Superpilot; 15th Oct 2012 at 02:00.
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Old 15th Oct 2012, 05:15
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If you have the correct ACARS page, the OLD (Operational Landing Distance) can be determined by a few button clicks.

In our operation, the fleet office have checked all our destinations and alternates for certain parameters. If within these then the calcualtion doesn't have to be done.
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Old 22nd Oct 2012, 22:12
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There are two related issues here. First the need to calculate landing distance before landing, and second, the use of Operational Landing Distances (OLD) as the source of advisory information.

EASA has identified the ‘Absence of in-flight landing performance assessment’ as a significant risk factor in overrun accidents - (European Aviation Safety Plan), section 4.1.1.
The inference is that operators should make an assessment of performance – distance, in addition to the EU OPS requirement to check the landing mass. This should improve awareness of the landing distance margin available – the safety margin; useful for unforeseen circumstances (inaccurate braking action) or system failures. Also, it aids operational planning, such as the level of braking required, the need for specific flight path / speed accuracy, etc.
The distance calculation adds to the extent and the value of landing plan (before landing briefing) by helping to identify risks and mitigation, e.g. what if the ‘wet runway’ is actually flooded – what is the additional landing distance required, or what reliance is being placed on reverse thrust for this landing.

Use of OLD has been proposed as a more practical source of advisory data to assess the required landing distance as it better represents what pilots achieve in daily operation. The basis of this was to be standardised (Airbus / Boeing) in the FAA TALPA meetings (FAA, EASA, etc); I have not seen any official outcome of this as yet.
The Airbus view of OLD in ‘Safety First’ (page 5) may not represent any industry consensus, nor be the basis of what is published / EFB, but it provides a good explanation of what has been proposed. Of note, it provides an interesting interpretation of EU-OPS1 requirement for the commander to check that the landing will be safe; this may conflict with some operational views of the use of factored distances in the before landing assessment.
As with any computation, the output depends on the input, thus factors such as the accuracy of reported wind or runway contaminant, and braking action (EASA safety items) require appropriate judgement; even when using worst case scenarios - is their ‘worst case’ the same as the actual situation, or do the ‘certain parameters’ provide sufficient safety margin in the assessed situation.

Overall ‘the new method of calculating landing distances’ must benefit safety; at least it should get pilots to think about (and understand) the essential parameters in assessing landing performance. One difficulty is to implement this without increasing workload, yet maintaining the full safety benefit. Perhaps most of the effort could be done on the ground – training and communication, and with sensible operational implementation pilots should know ‘before they go’ - or at least know before they go off the end of the runway.
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Old 23rd Oct 2012, 10:54
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AAARGH!! Again??

Damn!

I'll ty to find it, study it and then I will comment... Or mayb I will just wait six months for the next change?
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Old 23rd Oct 2012, 11:07
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M2002, I feel your pain mate. I'd wait a bit airbus is rolling out whole new concept of Vapp, X wind and OLD. As correctly pointed out the airborne phase is adjusted to 7 secs and 96% of Vapp. on the dry RWY, contaminated and auto land remains the same. You'll have the runway assessment matrix as well.
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Old 23rd Oct 2012, 12:36
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Yeah, So many changes are frustrating...

It is good that they always try to improve and make the best efforts for safety, I admit that. But it takes them too much trial and error to come up with each thing. I bet in six months there will be some debugging. And this generates frustration and a negative approach of many pilots to the new ways.

I have checked a few presentations and the idea is good. But I don't like the idea of Airbus pilots having to check landing distance every landing, even if they land in a 4000 m runway.

Why I don't like it?

Because they won't!!

Such mandatory procedures are doomed to be systematically violated. It is against human nature to do a stupid thing if you know that it is stupid, even if you are ordered to do it.

Calculating landing distance on a sunny day with an A319 before the briefing for an approach in DOH, (over 4,000 m) is one such thing. It is not if you are aproaching Londonderry in bad weather with a wet or worse runway, wings full of tankered fuel and full house...

I think that the first step of the landing distance assessment should be determining if such assessment is necessary at all, so that you only continue to step 2 if there is any doubt about the capability to land within the LDA.
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Old 25th Oct 2012, 12:47
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Micro / 9.G, this is not solely an Airbus initiative; but they do grasp opportunities for change where it improves safety.
OLD is an output of the FAA’s TALPA work, which is primarily aimed at reducing the risk of an overrun. It is anticipated that the FAA will require all manufactures to provide OLD and for operators to use this advisory data in their pre landing assessment (SAFO 06012).

Re “… the first step of the landing distance assessment should be determining if such assessment is necessary at all.”
I agree, but this assumes that there is some expertise and knowledge enabling such an assessment. Many of the younger generation of pilots do have a good depth of experience and apparently with increasing workload the opportunities are decreasing (#2).
Routine checking of landing distance and comparing performance may be tedious and repetitive (but no two landings are the same); however this can be the basis of skill enhancement (expertise - adding to their knowledge base), particularly if crews relate the pre landing check to the performance actually achieved.

I also agree that “… mandatory procedures may be systematically violated”, but this problem could reflect the way in which existing procedures are formed and taught. If a new procedure is seen as a rule, never to be violated, the ultimate ‘truth’, etc, then overrun incidents/accidents may continue, but if the prelanding check is seen as a trigger for risk assessment, a check and enhancement of situational knowledge, and an opportunity for advancing airmanship skills, then OLD and the prelanding assessment should help reduce the number of overruns.
Furthermore if this approach to safety is used elsewhere – a trigger for assessment, action, and learning, then many other in-flight thinking skills could be improved; but all of these start with a good knowledge base of the subject.
In this case it’s landing performance, thus understanding OLD and the differences between it and previous advisory data, and with certificated data is very important.
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Old 25th Oct 2012, 14:49
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st, i couldn't agree more moreover I'd go as far as labeling those actions from airbus as preemptive as it's a matter of time till the regulators set those rule in stone. As for the practibaility of the landing performance, it's SOP and is to be followed.
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Old 25th Oct 2012, 17:34
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Overruns always happen in wet or contaminates runways.

Spare us, at least, calculating OLD in dry runways, please. No flight ahould be ever dispatched to a runway where it is necessary to make the calculation...
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Old 25th Oct 2012, 20:53
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Re “…the practicality of the landing performance, it's SOP and is to be followed.” (#9)
Many of the current interpretations of SOPs involve ‘thoughtless’ adherence and is one of the potential problems in landing assessment and other flight operations.
The current FAA guidance (and without thought, the SAFO becomes a rule) requires a minimum distance margin of 15% over any advisory distance.

OLD provides a more realistic baseline on which to judge landing distance, … a judgement, not just a lookup table.
With OLD the airborne distances are longer and the braking action for assumed friction levels may also have been adjusted, but the reported braking action / braking effort to be used, wind, type of runway surface, etc, all require consideration before applying a safety margin. OLD may not consider variability or errors in reporting, thus judgement is required, and additional distance margins added as necessary.
SOPs may provide alleviation for emergency operation, but what is an ‘emergency’, and how might it relate to the expected landing situation; what risks can be justified when landing without a safety margin. SOPs cannot cover every situation; OLD provides a realistic minimum distance for specified conditions and other information to help balance any additional risk during landing.

The comparison of OLD – the required landing distance, with the landing distance available should be a standard procedure of airmanship. Using OLD and the judgement in continuing with a landing should be a rule of mind, but OLD per se isn’t a SOP or rule, the rule is don’t go off the end.
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Old 25th Oct 2012, 21:25
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well, st I prefer to keep it short and sweet. If you check pending revision of FCTM , FCOM QRH assessment of the landing performance using the RWY matrix is per se SOP. SOP is a guideline and shouldn't substitute neither sound judgment nor airmanship.
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Old 25th Oct 2012, 22:00
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SOP is a guideline and shouldn't substitute neither sound judgment nor airmanship
Where does this come from? 99.99999999% of the time sticking to SOP is the most sound judgement and best airmanship.

Most people I see who quote this sort of rhetoric do so just to excuse their own sloppiness or they consider themselves to know better.

Deviation from SOP should only happen in extremis. Otherwise the other members of the crew don't know where they stand.

Most of the minor incidents that I have seen, the initial causal factor was lack of adherence to SOP. Most serious incidents or accidents that I have read about have been due to deviation from SOP.

PLEASE ANYBODY READING THIS, STICK TO SOP (UNLESS YOUR SITUATION IS DIRE) AND THEN AVIATION WOULD BE SOOOOO MUCH SAFER!

Last edited by fmgc; 25th Oct 2012 at 22:02.
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Old 25th Oct 2012, 22:07
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Now back to the OLDs.

I have just done my first sim using them and they seem to work pretty well but do take a bit of getting used to.

There does seem to be an anomaly where if you have no failures but have to land overweight, the correction for carrying out the overweight landing procedure seems to be unduly punitive.

You can have a single hydraulic failure and get a shorter landing distance than you would for no failure, for a given overweight landing. Seems a bit odd to me but I guess there must be a good reason for it.
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Old 26th Oct 2012, 05:37
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Where does this come from? 99.99999999% of the time sticking to SOP is the most sound judgement and best airmanship.
Could you ever imagine it came directly from airbus?
The procedures contained in this Chapter are recommended by Airbus, and are consistent with the other Chapters of this manual. The Authorities do not certificate Standard Operating Procedures. The manufacturer presents them herein as the best way to proceed, from a technical and operational standpoint. They are continually updated and the revisions take into account Operator input, as well as manufacturer experience. In addition, Operators may amend them, as needed.
. Since you're such a black on white pedant, let's stick to the correct terminology so that everybody is in the same boat.
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Old 26th Oct 2012, 06:54
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The Authorities do not certificate Standard Operating Procedures.
Around here, the authorities do certify an airlines SOP's, the airline can amend them if desired provided they have a No Technical Objection letter from the manufacturer.

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Old 26th Oct 2012, 08:26
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9.G

What I am saying is that you shouldn't ever deviate from your Operator's SOPs.

And the Operator's SOPs ARE most definitely approved by the Authority! Under EASA you have to submit an NPA (Notice of Proposed Amendment) for changes to the Operations Manual and then wait for the local Authorities' approval of that NPA.
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Old 26th Oct 2012, 10:09
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well, the devil is the details as usual. This topic has been beaten to death here already but perhaps it's worth a while to review it again.
Firstly there's two different terms:
APPROVED: The Authority has reviewed the method, procedure or policy in question and issued a formal written approval.
ACCEPTED: The flight crew of large transport category aeroplanes typically use other sources of operating procedures information other than the AFM. Examples of other sources of operating procedures information include manufacturer- or operator produced operating manuals, Quick Reference Handbooks (QRH), System Pilot’s Guides and Emergency or Abnormal Checklists. For these aeroplanes, items such as cockpit checklists, systems descriptions, and the associated normal procedures should not be presented in the AFM if they are provided in other documents acceptable to the Agency. Normal procedures that are necessary for safe operation should be presented in the AFM, but the remaining normal procedures should be placed in the manufacturer produced FCOM (or other acceptable sources of operating procedures information). More on this topic here OneHandbookNew.dot
AC 25.1581-1 - Airplane Flight Manual - Document Information

Generally both EASA and FAA approve OM part A and accept the rest thus amendments to part A must be approved whereas part B can be amended by operator and is treated as accepted.

Last edited by 9.G; 26th Oct 2012 at 10:12.
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Old 26th Oct 2012, 10:14
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What is the difference between the FCOM and the AFM?
Airbus defines the content of the Airplane Flight Manual (AFM) based on the requirements issued by the Airworthiness Authorities in:

EASA Certification Specification (CS) 25, in paragraphs 25.1581 to 25.1591 and associated Acceptable Means of Compliance (AMC) 25.1581
FAA Federal Aviation Regulations (FAR) 25, in paragraphs 25.1581 to 25.1587 and associated Advisory Circular (AC) 25.1581.
The AMC and the AC also provide some information on the difference between the AFM and FCOM. For example:

Aeroplane Flight Manual (AFM). A EASA (or FAA) approved document that contains information (limitations, operating procedures, performance information, etc.) necessary to operate the aeroplane at the level of safety established by the aeroplane’s certification basis.

Flight Crew Operating Manual (FCOM). A document developed by a manufacturer that describes, in detail, the characteristics and operation of the aeroplane or its systems.

The AMC and the AC also include the following information on the content of the AFM compared to the content of the FCOM.

As more complex equipment was incorporated into transport category aeroplanes, many aeroplane and equipment manufacturers developed separate operating manuals intended for on-board use by the flight crew. These operating manuals are generically referred to within this AMC as Flight Crew Operating Manuals (FCOM). By locating information such as cockpit checklists, systems descriptions and detailed procedures in the FCOM, the bulk and complexity of the AFM can be kept manageable. As a result, the AFM for many transport aeroplanes has evolved into more of a reference document than a document used frequently by the flight crew. In recognition of the usefulness and convenience provided by these FCOMs, the normal operating procedures information in the AFMs for these transport category aeroplanes should be limited to those procedures considered ‘peculiar’ to the operation of that aeroplane type.

The flight crew of large transport category aeroplanes typically use other sources of operating procedures information other than the AFM.
Examples of other sources of operating procedures information include manufacturer- or operator produced operating manuals, Quick Reference Handbooks (QRH), System Pilot’s Guides and Emergency or Abnormal Checklists. For these aeroplanes, items such as cockpit checklists, systems descriptions, and the associated normal procedures should not be presented in the AFM if they are provided in other documents acceptable to the Agency. Normal procedures that are necessary for safe operation should be presented in the AFM, but the remaining normal procedures should be placed in the manufacturer produced FCOM (or other acceptable sources of operating procedures information).

The non-normal procedures section of the AFM for these types of aeroplanes should include, as a minimum, procedures dictated by the aeroplane’s system and failure modes, and may also include those emergency procedures listed in (...)this AMC (or AC).

Therefore, as explained in the introduction of the AFM and the FCOM:

This Airplane Flight Manual (AFM) is a reference document published in English by Airbus. It is not established as an operational document to be used directly by the crew in flight.

Flight crew documents available in flight must include an Operational Manual, with appropriate contents and language as required by the National Regulations.

The FCOM is the support documentation for flight crews, published in English by Airbus. It provides them with all the necessary information about the operational, technical, procedural, and performance characteristics of the A380 aircraft, to ensure safe and efficient operations of the aircraft during normal and abnormal/emergency situations, that may occur on ground, or in flight.

The FCOM is intended to be used:

Directly as flight crew operating manual, or
To provide operators with a basis for their development of a customized airline operations manual, in accordance with applicable local requirements
Is the content of the AFM included in the FCOM?
All procedures (emergency, abnormal and normal procedures) and limitations of the AFM are included in the FCOM, with additional information and guidance. As a general rule, and in agreement with the AMC and AC 25.1581, the FCOM provides additional data but should not disagree or be less restrictive than the AFM. Therefore, for each AFM revision, Airbus checks that the content in the FCOM is in accordance with the revised AFM. Similarly, for each FCOM revision, Airbus checks that the FCOM is in accordance with the AFM.

Some content of the AFM is not included in the FCOM. For example, the Configuration Deviation List (CDL) is not in the FCOM. Operators usually include the CDL in their MEL or DDG. The External Noise section is also not included in the FCOM because its content is not operationally relevant for flight crews.

It should be noted that discrepancies may temporarily occur between both manuals. This is due to different revision cycles between the two manuals (i.e. updates in both manuals may not be simultaneous).

Should the AFM and FCOM both be in the cockpit?
As explained in the introduction of the AFM, the AFM is a reference document and not an operational document to be used directly by the flight crew.

As a reminder, the operational regulations (EU-OPS 1, FAR 121) require that the AFM be on-board the aircraft. However, some local authorities accept that the operator removes the AFM from the aircraft if the Aircraft Operations Manual (AOM) contains all the necessary information for the flight crew.

For example, in EU-OPS 1 (OPS 1.130):
Manuals to be carried
An operator shall ensure that:
(1) The current parts of the Operations Manual relevant to the duties of the crew are carried on each flight;
(2) Those parts of the Operations Manual which are required for the conduct of a flight are easily accessible to the crew on board the aeroplane; and
(3) The current Aeroplane Flight Manual is carried in the aeroplane unless the Authority has accepted that the Operations Manual prescribed in OPS 1.1045, Appendix 1, Part B contains relevant information for that aeroplane.

FAR 121.141 provides similar information.



References
AFM / General / Introduction

FCOM / General Information / FCOM Purpose

EASA CS 25 (25.1581-25.1591) and AMC 25.1581
FAA FAR 25 (25.1581-25.1587) and AC 25.1581

EU-OPS 1 (1.130 Manuals to be carried)

FAR 121.141
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Old 26th Oct 2012, 10:15
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I don't disagree with what you are saying. But even if a change to Part B is made the Authority can and do ask for amendments to be made.

Notwithstanding all that, just because an SOP is accepted rather then approved doesn't give a pilot carte blanche to ignore SOP at his or her whim.
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