MEL definition

[jaja]

A quick question for the knowledgeable :

I am looking for the definition of "commencement of flight" with regard to MEL.

I want to find the present valid EASA documents on this.

Thank you !

[Skyjob]

‘Commencement of flight’ is the point when an aircraft begins to move under its own power for the purpose of preparing for take-off.
CS-MMEL (Certification Specifications and Guidance Material for Master Minimum Equipment List), Book 2 – Guidance Material, Subpart B, Master Minimum Equipment List, GM5 MMEL.120 Format and content of MMEL, Definitions And Explanatory Notes

For an older reference to JAR:
Commencement of flight is defined in JAR-MMEL/MEL.001(d) and .005(d) as “the point when an aircraft begins to move under its own power for the purpose of preparing for take-off.” In the case of a helicopter, it refers to the moment the helicopter commences air or ground taxi.

[torghabe]

So, MEL working on the ground until "the point when an aircraft begins to move under its own power for the purpose of preparing for take-off", after that point- QRH only.

[8che]

Not QRH only ! Life's not that simple. You would be foolish not to consult the MEL after taxi particularly for take off where the failure affects performance (or indeed something that will stop you returning from destination). That's Captaincy



For example Antiskid fail. The QRH says nothing but the MEL details the various takeoff performance penalties which you must still apply whether you have dispatched or not.

[Ollie Onion]

And just be careful because it CAN be airline specific. For example our aircraft aren't defined as dispatched until take off power is set. So any fault prior to takeoff is subject to MEL.

[john_tullamarine]

And just be careful because it CAN be airline specific

Generally, such will be the case.

The MMEL must be tailored to suit the operator and then processed through whatever regulatory approval process applies in the particular jurisdiction.

Sometimes the regulator will help out - developing an MEL is a painful exercise - as, for instance, in Australia where, for a period, CASA developed a generalised MEL (GMEL) for given Types which the operator could purchase for a fee much more attractive than the cost of a do-it-yourself animal. The GMEL system fell into disuse for reasons I have never discovered ..

Having had some involvement in MEL (and GMEL) development and defect investigation, I can only shake my head at the philosophy that holds a flight starts prior to takeoff ..

[om15]

EASA Air Operations Requirements ORO.MLR.105 MEL


"The Operator should include guidance in the MEL on how to deal with any failures that occur between the commencement of the flight and the start of the take off run".


As I understand it this guidance should include how to comply with the O&M procedures in that period between taxy and take off.

[torghabe]

8che, you"re on! ..."the point when an aircraft begins to move under its own power for the purpose of preparing for take-off, after that point- QRH only." It means- if you are on the RW and start moving for T/O. Sure, if you taxi to the RW and EICAS messages appears, NNCL first, MEL second, decision third. But if you start moving on the RW for T/O purpose, QRH- first and later you CAN use MEL, but for reference only.

[framer]

If you fly for an outfit that doesn't clarify exactly what is expected between pushback and comencement of the takeoff roll then you probably fly for a crap outfit.....if that is the case, the safety of the paying public relies on the Captains sound judgement and knowledge only. No systemic back up. It'll work well most of the time, it won't work well when the Captain is a fruit-loop.

[jaja]

Thank you Skyjob for the EASA reference.

When you read the definition on commencement of flight, it says
"the point when an aircraft begins to move under its own power for the purpose of preparing for take-off".
You could read this in two ways, either as beginning of the taxi phase, or the Take Off roll. But in the "old" JAR documents it says further :

"The operator's MEL should include procedures to deal with any failures which
occur between the start of taxi or push back and take-off brake release (see
ACJ to JAR-MMEL/MEL.001(d)). Any failure which occurs after take-off
commences should be dealt with as an in-flight failure, by reference to the
appropriate section of the Aircraft Flight Manual, if necessary."

(do you have the above as an EASA document ?)

As I understand it, "the point when an aircraft begins to move under its own power for the purpose of preparing for take-off" means the taxi phase, agree ?


If that is correct, then according the above, we should have tailored "on-ground Abnormal Procedures" (we fly Airbus`s) to cover the part of the flight from were it commences (beginning of taxi) until T/O ?

[Skyjob]

The EASA reference given is and can be explained either way. So it is up to an individual operator to establish the policy for its fleet and remove ambiguity.

As 8che mentioned, some operators rely on Captaincy to return to stand should a failure occur prior to departing during taxi, some require a return to stand no matter what.

Some failures (eg turnoff light failing) are benign but others (eg an antiskid failure) not so. Captaincy requires the Captain of the vessel to make an informed judgement call (decision) whether to continue the flight, having established the failure prior to departure, or to return to stand and have it looked at by Engineers, or speak to Engineers before continuing the flight without a return to stand, or to refer to MEL/CDL and assess if possible to apply restrictions for the flight to be undertaken instead delaying the aircraft further even though the restriction is not (yet) raised as a defect in the technical log of the aircraft.

There is no EASA defence to Captaincy and the area between the lines is in the hands of the Operator to define.

[SkyWagon737]

The definitions will not save your a$$ , but your decisions. Your company will ask you at the end. It is always good to check MEL for futher actions and it gives you vaulable information.

[LeadSled]

For example our aircraft aren't defined as dispatched until take off power is set

Folks,
That is close enough to the FAR definition for government work, the MEL applies up to the point of commencement of takeoff. It definitely does not mean commencement of taxiing.
Sorry I can't give a reference, too late at night.

PS: Have a look through a B744 or B767 etc. MEL, at the king of things that can happen between commencement of taxi, and ask yourself if you would want to get airborne.

[Sue Ridgepipe]

Our airbus MEL says this...
The provisions of the MEL are applicable until the start of the takeoff roll.
If a failure occurs between Pushback (OFF BLOCKS) and the takeoff roll, flight crew must complete all actions as required by the failure, including ECAM Actions and then refer to the MEL .

[mgTF]

MEL are NOT legally binding ONLY after the takeoff roll has begun.
From the moment the plane moves under its own power to takeoff roll, MEL are still legally binding.

The spirit of the sentence is that if you have an APU fire after pushback, first you deal with the fire drills as per QRH, then eventually consider a dispatch with an inop APU, though I guess first you want to investigate the fire damages :E

[Dufo]

After engine start, MEL and/or QRH apply in our joint. Plus common sense and captain discretion. All well written and explained.

[vilas]

Start of flight is although company specific there are far too many issues to consider before you take off and it is not possible or practical to apply MEL during taxi and if you ignore it because by definition the flight has begun it could have serious implications and land you in trouble. The least of which is getting grounded at destination where maintenance is not available. Prudent option is to return to dispersal switch off and do the needful.

[Skyjob]

Prudent option is to return to dispersal
And herein lies the discretion of application.
If a failure would occur at home base with engineering support it may be more prudent to return to stand, whereas if the same failure had occurred down-route at an outstation it would probably more prudent to "return to dispersal".
Same failure, different choice made by, but both governed by the same definition in MEL, both correct.

[jaja]

So please give examples of which major airlines in Europe, apply the MEL up until takeoff power is set, and not just until start of taxi.

[PENKO]

Just to be clear, it's misleading in this discussion to say 'the MEL applies'.
The MEL does not 'apply' anything. What applies is that you go back to the gate, open the doors, enter the defect in the tech log, call an engineer, wait an hour for the engineer to arrive, and THEN, if the fault cannot be cleared in a reasonable time frame, possibly apply the MEL in order to dispatch.

[PENKO]

This is what EASA states in its document 'Certification Specificationsand Guidance Material for Master Minimum Equipment List CS-MMEL':
‘Commencement of flight’ is the point when an aircraft begins to move under its own power for the purpose of preparing for take-off.
[...]
Operators should include guidance in the MEL to deal with any failures which occur between the commencement of the flight and the start of the take-off.


So it is very, very, very clear till what stage a defect needs to be entered in the Tech Log, rectified by an engineer or possibly deferred under the MEL: the release of the parking brake for taxi.

You'd be surprised how many pilots don't grasp this simple fact

[sonicbum]

the release of the parking brake for taxi.


100% agree, my previous operator had exactly the same wording in our OM(A) and that cleared any possibile doubts amongst the pilot population. My current one uses the wording "commencement of the flight" which should still be pretty clear but does indeed create confusion sometimes over a widespread fleet. As we all know most of the times wording is kept in such a way that it can be twisted and interpreted as needed depending on whom is supposed to be right or wrong :E

[pineteam]

Same as PENKO.

From our FOM:

''The crew must refer to the MEL if a failure occurs or a component is degraded or a function is inoperative before taxi-out. If a failure occurs between the start of taxi ( when the aircraft begins to move under his own power) until the start of the takeoff roll it is subject to good pilot judgement and airmanship. The PIC may refer to the MEL to make an assessment before any decision to continue the flight is taken. This is particularly true for those failures that might affect the takeoff performance (i.e loss of spoilers, brake failure, etc.).''

[spannersatcx]

Just to be clear, it's misleading in this discussion to say 'the MEL applies'.
The MEL does not 'apply' anything. What applies is that you go back to the gate, open the doors, enter the defect in the tech log, call an engineer, wait an hour for the engineer to arrive, and THEN, if the fault cannot be cleared in a reasonable time frame, possibly apply the MEL in order to dispatch.

Maybe where you are, WE are on the headset for departure at our airline! :p

[jaja]

No it is not clear when to apply the MEL or the Abnormal checklist, but it used to be clear (up to approx 15 years ago).

The MEL should be applied up until setting takeoff power if you have failures on startup/taxi, and when airborne you look into the Abnormal checklist. That is the way we used to do it.

Let me give an example why : on taxi out you have an ECAM warning, and this failure is a “NO DISPATCH” according to the MEL. Common sense would be not to continue the flight, but as it is company procedure in many places, it is up to captain to decide if it is OK to continue (after using “good airmanship etc”.

In todays complex aircraft it should not be up to the captain to decide that. The MEL should be used/applied up to setting takeoff power.

Please give examples on in which European companies is the MEL used/applied that way (up to setting takeoff power) ?

[pineteam]

Many MEL '' No dispatch'' are conservative and therefore not busine$$ friendly so it would not necessary make sense to return to the gate especially if you are in a remote area where they would not be able to fix the aircraft. Most of the time, it will have zero effect on the flight as there is redundancy. As long as you are aware of the potential consequences and comfortable with it. Then why not continue. I personally like the way it is. :)

[jaja]

Yes Pineteam, that is also the answer I get from many, BUT if we have such good system redundancy why should we in the first place appy the MEL restrictions if we have failures before pushback ? It does not make sense !

[pineteam]

Maybe since we are still att the gate, probably with no pax on board with engines shut down, and maintenance available it's worth it to try and fix it? During taxi we are left alone. xD
Just speculating. I'm not sure why. xD

[sonicbum]

Yes Pineteam, that is also the answer I get from many, BUT if we have such good system redundancy why should we in the first place appy the MEL restrictions if we have failures before pushback ? It does not make sense !

The MEL provisions also consider the worst case scenario of a subsequent inflight failure of another critical system and therefore protects You accordingly. Once the applicability of the MEL ceases it is up to You to cater for all the different scenarios that could happen and decide. Regardless of what the MEL says the final word is anyway always with the flight crew (ie the Captain) if a more restrictive interpretation of the MEL is required given the conditions of the day.

[jaja]

The MEL provisions also consider the worst case scenario of a subsequent inflight failure of another critical system and therefore protects You accordingly. Once the applicability of the MEL ceases it is up to You to cater for all the different scenarios that could happen and decide. Regardless of what the MEL says the final word is anyway always with the flight crew (ie the Captain) if a more restrictive interpretation of the MEL is required given the conditions of the day.

yes SONICBUM that is exactly why you should apply the MEL up until setting takeoff power = no normal captain or technician can fully understand the consequences of flying with a “NO DISPATCH” failure on todays complex aircraft.

So I ask again : are there examples on a European company who apply/uses the MEL up until setting takeoff power ?

[PENKO]

No it is not clear when to apply the MEL or the Abnormal checklist, but it used to be clear (up to approx 15 years ago).

The MEL should be applied up until setting takeoff power if you have failures on startup/taxi, and when airborne you look into the Abnormal checklist. That is the way we used to do it.

Let me give an example why : on taxi out you have an ECAM warning, and this failure is a “NO DISPATCH” according to the MEL. Common sense would be not to continue the flight, but as it is company procedure in many places, it is up to captain to decide if it is OK to continue (after using “good airmanship etc”.

In todays complex aircraft it should not be up to the captain to decide that. The MEL should be used/applied up to setting takeoff power.

Please give examples on in which European companies is the MEL used/applied that way (up to setting takeoff power) ?







If you ask me what is whise, then yes, of course, the MEL is one of the things you consider in your scenario of ECAM during taxi. The MEL is also a wonderful companion with ECAM in flight if time permits, or reading FCOM in bed at home.

If you ask what are the rules, then the rules are very clear, see my quote in an earlier post.
If you disagree with this, then please explain why. I pointed out that EASA also has the provision regarding failures during taxi. This should answer your initial question.

As for your point that we need tailored on ground procedures for dealing with failures, well, that's exactly what you have in your MEL: once dispatched but before TO, complete the QRH/ECAM and consider the implications of the MEL, maintenance facilities etc and then decide to go or not. But you are not bound by the MEL at that stage.

[jaja]

yes PENKO, but the average flightcrew/technician can not “consider the implications of the MEL”

so if you as a flightcrew decide to continue the flight, after having a failure during taxi that is a “NO DISPATCH” according to the MEL, then indeed you are on “un known ground”.

Why not be professional, and consider the aircraft “not airworthy” if you have a “NO DISPATCH” fault during taxi ?

[PENKO]

That's a different discussion jaja. An interesting discussion for those quiet cruise portions on a long flight indeed, but still a different discussion.
Now we can produce a long list of failures and ask 'would you take off'. Or we can ask one simple question: why have the regulators chosen the moment of taxi as the start of a flight with respect to defect handling? Apparently they trust our professionalism.

Fair enough, no?

[pineteam]

Why not be professional, and consider the aircraft “not airworthy” if you have a “NO DISPATCH” fault during taxi ?


Because a return to the gate can be extremely expensive if for instance the flight is cancelled. Being safe is good but you can’t be overly safe and competitive at the same time. Airlines main target is to make profit. It’s a business. We should not forget that.
How many times have you heard of a serious incident/accident after a crew decided to continue a flight after a « no dispatch failure » during taxi? Must be extremely rare otherwise I would expect that we apply the MEL the way you describe.

[sonicbum]

How can you apply requirements and restrictions of the MEL when (M) is required, without returning to the gate?

Well You can't that's why You need to balance risks, assess the situation and come up with a decision using all the available tools. If possible a phone/satcom/HF call to your maintenance team while at the holding point could give you valuable inputs to come up with your decision and if you're still stuck a call to your duty pilot (if there is one where your work) can help you out as he is going to speak on behalf of the company even though he's not going to decide for you but most likely give you "food for thoughts". Main thing when in a grey area is to get as many inputs as possible before jumping to a decision and being told "oh yeah but you could have talked to etc..". In the end no one decides for You but if the feeling You get from all around is that it smells "dodgy" then the parking bay is where you are heading to.

[hans brinker]

https://cimg3.ibsrv.net/gimg/www.gmforum.com-vbulletin/1536x1586/img_0149_e63d7f7f86ead50744481339f7813d3f83d4121d.jpg

Clear I would hope...

[PENKO]

This is not EASA-based.
So to be clear, you would go back to the gate for say..a burnt turn off light?

[PENKO]

Nice idea, but I would suggest it would be a brave manager or engineer who would authorise departing without a tech log entry. If you having enough doubt to call them ...

Ever been told “it’s OK” and then asked of it in writing? I did once, and I got it (I didn’t agree with CP and engineering that I should do an engine run after a problem). Carried out the requested engine run ... very expensive bang followed. Play safe.

Just my 2 cents worth.

Why so paranoid? It's perfectly legal, no tech log entry necessary after you've dispatched. Any professional engineer will have no hesitation to advise you to go or not go, in writing, or on a recorded phone conversation.

I'm glad I work with sensible professionals who are not afraid to offer sensible advise or take sensible decisions. Also in writing when requested.

[FlightDetent]

The regulation is worded the way it is for a reason. By people who - unlike common line folks such as us here (both FD an MX) - actually do know the backgroud, understand the implications, and are expertly trained in writing legal documents.

jaja, have you considered if perhaps the strong discord between your convictions and the law could be due to lack of education on the side of the liveware unit? There are valid answers to your queries, yet until you pass through that door they could remain out of sight.

[767 pilot]

Boeing 767 DDG quotation "Upon completion of any applicable procedures and prior to takeoff, the operator’s MEL should be consulted to determine if relief is available for continued operation with system faults displayed at the alert level (Warning, Caution, Advisory).", so Boeing's policy is: if after or during engine start and before TO there is an alert message: 1) do the respective non-normal checklist (NNC), 2) check the DDG or MEL to make decision. For me, it is still unclear what to do if on this stage and before ETOPS entry point there some issues related to ETOPS MEL ITEMS and which usually not considered for NON-ETOPS flights.

[speedbird787]

In my company MEL is applicable till take off thrust this is the flow chart we follow as per OMAhttps://cimg1.ibsrv.net/gimg/www.gmforum.com-vbulletin/1080x1920/screenshot_20180713_234150_cf4faa2ddc4e872f13a46b9a860d97a83 a3c1108.png
https://cimg2.ibsrv.net/gimg/www.gmforum.com-vbulletin/1080x1920/screenshot_20180713_234155_5d6bfa9f93359d7939af3596f07883e36 7bec338.png

[pineteam]

This is what EASA states in its document 'Certification Specificationsand Guidance Material for Master Minimum Equipment List CS-MMEL':

So it is very, very, very clear till what stage a defect needs to be entered in the Tech Log, rectified by an engineer or possibly deferred under the MEL: the release of the parking brake for taxi.

You'd be surprised how many pilots don't grasp this simple fact

Hello Guys,

I just have a doubt about this. Imagine you have closed the doors, about to push back and you have an ECAM : IR1 fault. Obviously you check the MEL it’s a go Item. Only thing you have to do to switch IR3 to captain side. My question is: Do I need to call maintenance to release the aircraft in that condition? From what I understand it’s not required; We must refer to the MEL until aircraft moves on his own power but it does not say we need maintenance to release the aircraft again in case of failure.. According to our FOM, the captain takes the responsibility of the aircraft after doors are closed. My understanding is that before taxi, in case of failure, we refer to MEL but if no maintenance action is required therefore there is no need to call maintenance again. Isn’t it?
I had this issue today in Shanghai Hongqiao but the IR self recovered after realignment. Pilots flying in China know the nightmare it is to get ground personal after doors closed... xD

[FlightDetent]

Airline's Operating Manual, more specifically the Operator's Approved MEL Preamble is where you find the binding definition.

With the exception of some strange ideas or achieved flexibility goals, the general idea is

A moment of dispatch is defined. Typically the first movement under own power for the purpose of taking-off.

Before dispatch, any failure
- should be written in the book
- must be approved for release by the responsible maintenance officer as per MEL which is binding
- MEL paperwork needs to be filled and signed by an authorized person (captain in some cases)

After dispatch
- the MEL (which is by its definition more restrictive compared to ABN section of AFM / FCOM) does not need to be taken into account

These would be the legal boundaries.

"Refer to MEL" at a time when MEL is still controlling = "Apply the authorized procedures, close with a new maintenance release"
There is no other explanation.

[pineteam]

Hi FlightDetent,
Thank you for your time. Like you mentioned, any failure should be written in the techlog but I failed to find official documents saying black and white than maintenance shall release the aircraft again. I asked one TRI from my airline and he agrees with what you say. I just wish it was a little more explicit in our manuals xD.

[FlightDetent]

I worded the above (and erased some) strictly on purpose so that the naked truth stands out.
- post the dispatch moment: crew decides what to do (does not exclude liaison)
- pre-dispatch, only three options exist
a) the A/C is deemed faultless
b) the snags are processed and signed-off
c) it is effectively grounded with an open defect.

This knowledge helps to interpret the various guidance found in the manuals, and apply their advice in the correct sequence and order of priority.

The Continued Airworthiness (of which I know absolute zilch) is a standalone area of industry expertise, and they have relevant NAA branch telling them how to arrange things too. Another point, imagine if we admitted Airbus-language was a standalone linguistic category, you personally operate in a quad-language environment! On top of it, various Tech Logs have various protocols on who is allowed to sign what, etc, etc...

Out in the field, same like you experienced, I think everyone follows rules and decision-making algorithms that attempt to achieve the above while having weak, contradictory or even missing links.

I am not sure who's quantum computer is the fastest, Google, IBM or Intel. In case you wanted to fry its quarks, ask a simple question: How do I officially record a successful inflight reset after landing on an outstation, so that no delay, operational or financial penalty is incurred as a consequence.

BTW (rhetorical) : What actually is the Maintenance Release and when you really need to have (a new) one? (varies between operateors)

[hans brinker]

That's a different discussion jaja. An interesting discussion for those quiet cruise portions on a long flight indeed, but still a different discussion.
Now we can produce a long list of failures and ask 'would you take off'. Or we can ask one simple question: why have the regulators chosen the moment of taxi as the start of a flight with respect to defect handling? Apparently they trust our professionalism.

Fair enough, no?
Not really. After flying JAA for a few years, I now fly FAA. According to some we are cowboys here, but I m surprised at the cavalier attitude towards failures I see here on this every thread.For discrepancy between off block and take off we have a procedure to to follow. At some point, if we can't get it resolved we have to either MEL it (if it is pilot defferable) or return to the gate. I am utterly lost how you would ever think it is acceptable to take an airplane airborne with a known failure just because it happened after you released the parking brake, but before you got to the runway.

[hans brinker]

This is not EASA-based.
So to be clear, you would go back to the gate for say..a burnt turn off light?
​​​​​​ To answer your question from last year. No, I would not, because a turn off light is FD (Flight crew Deferrable) so I can MEL it while holding short, and continue. I would however return to the gate for a door unsafe warning, even if it is FD, and the ECAM tells me I can continue.

[jaja]

I am utterly lost how you would ever think it is acceptable to take an airplane airborne with a known failure just because it happened after you released the parking brake, but before you got to the runway.

Spot on Hans Brinker - that is exactly the reason why I started this tread.........

In my opinion the MEL should be applied up until setting takeoff power if you have failures on startup/taxi, and when airborne you look into the Abnormal checklist. That is the way we used to do it.

Let me give an example why : on taxi out you have an ECAM warning, and this failure is a “NO DISPATCH” according to the MEL. Common sense would be not to continue the flight, but as it is company (EASA reg) procedure in many places, it is up to captain to decide if it is OK to continue (after using “good airmanship etc”.

In todays complex aircraft it should not be up to the captain to decide that. The MEL should be used/applied up to setting takeoff power

[FlightDetent]

hans, I'd argue what is displayed here is not cavalier (ehm) attitudes but the word of applicable law. At least that's what I tried to relay in my post, happy to underline the intention now. And that law does not preclude you from returning back. Au contraire it forces you to apply judgement and exercise authority when taking the decision whether to fly or taxy back.

Moreover, the principle of dispatch moment being the start of taxi under own power is also known to the people who write and certify the MMEL.

Your second point is an excellent illustration to the different protocols (with missing links that I allude to above): Imagine that in pinteam's situation: his entry in the logbook must be counter-signed by approved line-maintenance. So, unlike you, he has the need to continue without recording it pre-takeoff, and the law entitles him to do so. Different strokes for different players.

Writing the above I already got two ideas (case studies) where - based on your wisdomly posting history - I'd bet half a bitcoin you personally (in the door warning situation) would just set the burners full and be gone to worry about the paperwork later.

But there's a better story, not a week old. Upon receiving the taxi instruction, I flicked the taxi LT switch and nothing happed. That's pre-dispatch.
- hhhmmm ....?

[FlightDetent]

In my opinion the MEL should be applied up until setting takeoff power if you have failures on startup/taxi, and when airborne you look into the Abnormal checklist. That is the way we used to do it. Well, 60 years of aviation history and expertise work on Airworthiness came to a different conclusion. Perhaps you and the law need to agree on disagreeing. The alternative solution is a lack of insight on one side of the argument.

[hans brinker]

hans, I'd argue what is displayed here is not cavalier (ehm) attitudes but the word of applicable law. At least that's what I tried to relay in my post, happy to underline the intention now. And that law does not preclude you from returning back. Au contraire it forces you to apply judgement and exercise authority when taking the decision whether to fly or taxy back.

Moreover, the principle of dispatch moment being the start of taxi under own power is also known to the people who write and certify the MMEL.

Your second point is an excellent illustration to the different protocols (with missing links that I allude to above): Imagine that in pinteam's situation: his entry in the logbook must be counter-signed by approved line-maintenance. So, unlike you, he has the need to continue without recording it pre-takeoff, and the law entitles him to do so. Different strokes for different players.

Writing the above I already got two ideas (case studies) where - based on your wisdomly posting history - I'd bet half a bitcoin you personally (in the door warning situation) would just set the burners full and be gone to worry about the paperwork later.

But there's a better story, not a week old. Upon receiving the taxi instruction, I flicked the taxi LT switch and nothing happed. That's pre-dispatch.
- hhhmmm ....?
Well, I'm sorry to disappoint you, but I had the door warning on a central America red-eye turn (and my overnight bag was in the hotel in KFLL) and I went back to the gate. Took them 15 minutes to defer, got back to the hotel in time for breakfast. I replied to the light question already. I generally agree with you on here, and as a former ACMI and 91K pilot know very well how to keep the aircraft moving, but I am surprised the airlines in the EU give that much latitude. As far as Pineteam's example, he hadn't started to move on it's own power, so the door should have been reopened. Not easy, but safe.
Also, in a previous post you questioned what to do about successful reset of systems in flight, we have an "info only" write up in the AML for that.

[FlightDetent]

You are not listening, that's what disappoints me (also underestimating my imagination about the case studies, a little ;) ) . It is not the airlines, it is the law. The Airlines OTOH put protocols and more restrictive rules forward, exactly in the direction you guys are thinking.

You are right about pinteam's case, I mixed that up.

The "info only" is an agreed dinousaur and is specifically prohibited with many airlines on the EU side. It carries no meaning, once a record is done it becomes an issue to be solved. Pilots have no say how to interpret an failure, the authorized Maintrol shift leader does. I assume in your case the "for info" has an explicit definition somewhere in the Continued Airworthiness QA manuals, hence you can use it. No surprise, there is a reason why the good US airlines on average are ahead of the world.

Let's not fight in close quarters. What is the broader perspective?
- everyone has the same goal, only getting airborne with an airworthy aircraft that you trust and that includes neat and proper paperwork trail
- everyone is trying to do their honest best, playing the cards at hand and following the rules
- but we are not walking on the same path towards that goal.

This thread is about discussing what type of gear either of the parties carry on their trail. You mentioned the US being viewed as cowboys, the look from the opposite direction look is EU formalists. Guess what, I think this is bloody relevant - dare to read my mind with more success this time?

[jaja]

Well, 60 years of aviation history and expertise work on Airworthiness came to a different conclusion. Perhaps you and the law need to agree on disagreeing. The alternative solution is a lack of insight on one side of the argument.

Dear FlightDetent, I disagree with you

Up to approx. 15-20 years ago, the MEL was applicable up to setting T/O thrust. Then JAA changed the regulation to what we have today (see EASA extract below)

The aircraft does not become any more airworthy, just because you have started to taxi.

So if a defect is a NO GO item according to the MEL, is does not have any positive effect on the airworthiness off the aircraft that you have started to taxi. I think we can agree on that?

Then EASA says the following : “any decision to continue the flight should be subject to pilot judgement and good airmanship”

OK now, so the aircraft manufacturer has evaluated system integrity and have come up with a list in the MMEL of NO GO items. This is because the aircraft manufacturer thinks is a not a good idea getting airborne with these defects. So how do you think a captain can use his/her “pilot judgement and good airmanship” and evaluate that is OK to fly with this defect, just because we have started to taxi ? You can not !

Please note the following very important words from EASA : “The operator should include guidance in the MEL on how to deal with any failures that occur between the commencement of the flight and the start of the take-off”. This actually means the operator has to produce what you can call an “On ground abnormal procedure”. But off course nobody has the resources to do that, so instead you should do what we did before : MEL is applicable up until setting T/O thrust

AMC1 ORO.MLR.105(d)(3) Minimum equipment list EXTENT OF THE MELThe operator should include guidance in the MEL on how to deal with any failures that occur between the commencement of the flight and the start of the take-off . If a failure occurs between the commencement of the flight and the start of the take-off , any decision to continue the flight should be subject to pilot judgement and good airmanship. The pilot-in-command/commander may refer to the MEL before any decision to continue the flight is taken.

[pineteam]

OK now, so the aircraft manufacturer has evaluated system integrity and have come up with a list in the MMEL of NO GO items. This is because the aircraft manufacturer thinks is a not a good idea getting airborne with these defects. So how do you think a captain can use his/her “pilot judgement and good airmanship” and evaluate that is OK to fly with this defect, just because we have started to taxi ? You can not !


Yes you can because many « No dispatch » conditions are extremely conservative. And if you are outstation with no maintenance, you happy that you can legally proceed. I mean come on, modern airliners have so many redundancies. So if I understand correctly you would not go if you lose 1 computer out of 3 on a an A320 cause Mel says no dispatch but would happily fly a Cessna 172 relying on one engine? xD. I’m obviously not talking about hydraulic or serious failure that is a no brainer to go back. Once again it’s all about good judgement and airmanship.

[jaja]

Yes you can because many « No dispatch » conditions are extremely conservative. And if you are outstation with no maintenance, you happy that you can legally proceed. I mean come on, modern airliners have so many redundancies. So if I understand correctly you would not go if you lose 1 computer out of 3 on a an A320 cause Mel says no dispatch but would happily fly a Cessna 172 relying on one engine? xD. I’m obviously not talking about hydraulic or serious failure that is a no brainer to go back. Once again it’s all about good judgement and airmanship.

Pineteam, this tread started with the following ; "A quick question for the knowledgeable ".

In my humble opnion, if you don`t have anything serious and professional to add to this discussion, then please leave the discussion to others.

I wish you a good day

[pineteam]

Pineteam, this tread started with the following ; "A quick question for the knowledgeable ".

In my humble opnion, if you don`t have anything serious and professional to add to this discussion, then please leave the discussion to others.

I wish you a good day

Hahaha. I know this forum is full of pilots wanabee but I’m not one of them. You are barking at the wrong dog.
I just gave my point of view why I think it’s safe depending of the case to continue the flight following a failure after taxi.
The law says we can. Deal with it.
have a good day too. =)

[hans brinker]

Yes you can because many « No dispatch » conditions are extremely conservative. And if you are outstation with no maintenance, you happy that you can legally proceed. I mean come on, modern airliners have so many redundancies. So if I understand correctly you would not go if you lose 1 computer out of 3 on a an A320 cause Mel says no dispatch but would happily fly a Cessna 172 relying on one engine? xD. I’m obviously not talking about hydraulic or serious failure that is a no brainer to go back. Once again it’s all about good judgement and airmanship.

In aviation it pays to be conservative, and the reason for 3 computers isn't just redundancy, but being able to vote. I for sure would go back to the gate with any no-dispatch discrepancy. The fact that you and I (both experienced pilots) disagree about this is all the proof I need to conclude it should not be left to the judgement of the pilot.
I don't fly single engine myself but as far as I can remember you cannot fly commercial single engine with pax. Do you think that is a n extremely conservative attitude from the regulator?

[FlightDetent]

hans brinker My last post, if you'd take my word for it, was written with enthusiasm. Instead of displaying that, the resulting verbiage came out quite confrontational, nasty. Sorry about that.

Line up and with the tkof clearance turn on the LDG lights but one of them is not working: The EU rules allow you to go straight away. I understand that the US rule is to vacate at the first exit, fill the paperwork and start over. I am not entirely convinced this would actually happen.

The idea I had is that the formalist EU are not allowed to interpret the "meaning of rules" but required to stick to them at all times. Butterfly wing effect, then we try not to create rules which will be impossible to follow. (Loose reference: AC 120-71 - Effective SOP section of the document, namely Once established, the SOPs must be applied with consistency and uniformity throughout the operation).

---jaja If something has changed 20 years ago, based on 40 years of previous experience and the new version is in force today, it still is 60 years of experience - combined.

You constantly refer to somebody departing with a NO GO item. Why would anyone do that?

Quoting the AMC --- that acronym actually means the mandatory and only (unless otherwise approved by the NAA) approved means of compliance --- That's an important one.

It says the MEL (OM-B section MEL) does not get approved by the NAA until a procedure for the taxi-phase is drawn and inserted there. For which a typical wording is "open the MEL and use the NO DISPATCH / DISPATCH POSSIBLE as a key to figure out whether to taxi back or go, if unsure must contact the MCC duty officer".

When you say nobody has that text, my mileage really varies. It sounds like an incomplete and non-compliant OM. I could see the NAA being at fault where you stand but not the legislation itself - proven by that very quote.

---


@pinteam The two of us and hans operate the same airplane. I strongly suggest that if the MMEL says NO DISPATCH on that thing, you really do not want to fly it.

Remember, what the evaluation criteria between NO DISPATCH and RELIEF POSSIBLE are. It is the expected combined effect after another, independently caused, failure on the same system. The resulting state becomes the key. Hence you can do 1 brake inop, but not 2. Or taxi and tkof LT inop for a night - but only as long as both LDG LTs are operative.

Another example: during F/CTL controls check while taxiing already, ELAC 1 PITCH FAULT. Reset per QRH, re-action the F/CTL check (part of the QRH proc): the failure re-appears. That is a NO GO by the book. Seeing those words means the smart engineers decided the state after ELAC 1 PITCH FAULT does not have the redundancies anymore.

Compare that ELAC 1 PITCH against the case of a single PACK (go item): if the opposite would fail, you lose all pressurization sources, but the hull will contain pressure somewhat - there still is a backup in place. Touch your heart, not much of it!

Well, where it says NO DISPATCH for the ELAC 1 PTICH FAULT it means the equivalent result after a second failure would be worse than having no packs at all.

[pineteam]

In aviation it pays to be conservative, and the reason for 3 computers isn't just redundancy, but being able to vote. I for sure would go back to the gate with any no-dispatch discrepancy. The fact that you and I (both experienced pilots) disagree about this is all the proof I need to conclude it should not be left to the judgement of the pilot.
I don't fly single engine myself but as far as I can remember you cannot fly commercial single engine with pax. Do you think that is a n extremely conservative attitude from the regulator?

Hello Hans Brinker,
Many of my flights are shorts ones and we carry lots of fuel. Our company is very conservative for the fuel policy and our aircraft are very well maintained. We very seldom have MEL at the first place. Maybe I sounded like a cowboy but I’m not, and the decision to go back to the gate or not would be taken with the FO and maybe with the company if I have time to stop and send and Acars message or give a call. I never had to make that decision yet actually; Only had “can go failure” maybe twice in 5 years.
Commercial Single engine operation is allowed in some countries, I flew Cessna Caravan for 2 and half years in Zambia. But yes, I undestand why it’s forbidden in most countries. = )

[hans brinker]

Hello Hans Brinker,
Many of my flights are shorts ones and we carry lots of fuel. Our company is very conservative for the fuel policy and our aircraft are very well maintained. We very seldom have MEL at the first place. Maybe I sounded like a cowboy but I’m not, and the decision to go back to the gate or not would be taken with the FO and maybe with the company if I have time to stop and send and Acars message or give a call. I never had to make that decision yet actually; Only had “can go failure” maybe twice in 5 years.
Commercial Single engine operation is allowed in some countries, I flew Cessna Caravan for 2 and half years in Zambia. But yes, I undestand why it’s forbidden in most countries. = )
Hi Pine,
I wasn't suggesting you are a cowboy, it is my companies policy to handle problems during taxi out this way. I really mean it should not be up to the judgement of the pilot, because in my opinion that puts to much go pressure on the pilot. In my company we have a flow chart (posted above). Even if I can reset the system (with an published reset procedure or phone help from MOC), I have to enter the successful reset in the AML for tracking and advise MOC. For anything else, back I go.
Also I meant to say SE IFR Commercial, but even that may be allowed in some places...

[hans brinker]

hans brinker My last post, if you'd take my word for it, was written with enthusiasm. Instead of displaying that, the resulting verbiage came out quite confrontational, nasty. Sorry about that.

Line up and with the tkof clearance turn on the LDG lights but one of them is not working: The EU rules allow you to go straight away. I understand that the US rule is to vacate at the first exit, fill the paperwork and start over. I am not entirely convinced this would actually happen.

The idea I had is that the formalist EU are not allowed to interpret the "meaning of rules" but required to stick to them at all times. Butterfly wing effect, then we try not to create rules which will be impossible to follow. (Loose reference: AC 120-71 - Effective SOP section of the document, namely Once established, the SOPs must be applied with consistency and uniformity throughout the operation).

---jaja If something has changed 20 years ago, based on 40 years of previous experience and the new version is in force today, it still is 60 years of experience - combined.

You constantly refer to somebody departing with a NO GO item. Why would anyone do that?

Quoting the AMC --- that acronym actually means the mandatory and only (unless otherwise approved by the NAA) approved means of compliance --- That's an important one.

It says the MEL (OM-B section MEL) does not get approved by the NAA until a procedure for the taxi-phase is drawn and inserted there. For which a typical wording is "open the MEL and use the NO DISPATCH / DISPATCH POSSIBLE as a key to figure out whether to taxi back or go, if unsure must contact the MCC duty officer".

When you say nobody has that text, my mileage really varies. It sounds like an incomplete and non-compliant OM. I could see the NAA being at fault where you stand but not the legislation itself - proven by that very quote.

---


@pinteam The two of us and hans operate the same airplane. I strongly suggest that if the MMEL says NO DISPATCH on that thing, you really do not want to fly it.

Remember, what the evaluation criteria between NO DISPATCH and RELIEF POSSIBLE are. It is the expected combined effect after another, independently caused, failure on the same system. The resulting state becomes the key. Hence you can do 1 brake inop, but not 2. Or taxi and tkof LT inop for a night - but only as long as both LDG LTs are operative.

Another example: during F/CTL controls check while taxiing already, ELAC 1 PITCH FAULT. Reset per QRH, re-action the F/CTL check (part of the QRH proc): the failure re-appears. That is a NO GO by the book. Seeing those words means the smart engineers decided the state after ELAC 1 PITCH FAULT does not have the redundancies anymore.

Compare that ELAC 1 PITCH against the case of a single PACK (go item): if the opposite would fail, you lose all pressurization sources, but the hull will contain pressure somewhat - there still is a backup in place. Touch your heart, not much of it!

Well, where it says NO DISPATCH for the ELAC 1 PTICH FAULT it means the equivalent result after a second failure would be worse than having no packs at all.



No offense taken, and thanks for getting back to me as I wasn't sure how to reply to your last post ;) . You are right in, I would definitely have continued the take off with one light failed, and completed the write up in the air (provided I knew the light was deferrable by the FC, and not required for the operation), a system fault would most probably be treated different.

Also great words of advise about the no go items, as a recent accident shows:

Accident: Smartlynx A320 at Tallinn on Feb 28th 2018, runway excursion after bad touch and go due to elevator control completely lost

https://avherald.com/h?article=4b57c3dd/0000&opt=0

They reset the ELACs a few times, left one off, the other failed, so no sidestick input possible while hurling down the runway....