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737-700 M. E. L.

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737-700 M. E. L.

Old 16th Nov 2004, 16:17
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Never worked on a transport aeroplane yet when the autopilot(s) is/are not listed in the MEL Chapter 22. Also lists individual items that affect dual-land ops like yaw damper/LSAS channels, autothrottle servos etc and items in ATA34 that affect automation ie FMS SPD/NAV/PROF modes etc. They're all there in the MEL
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Old 16th Nov 2004, 18:51
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Cool

I don't agree. If there is a defect and it is not listed in the MEL, the aircraft cannot be dispatched. If it IS in the MEL, it is still at the pilots discretion to NOT accept the aircraft
Wizofoz, quite correct I think. I would never dispatch at discretion on a non-MEL item.
What rubbish, and if you don't believe me have a look at the UK CAA safety website!

If you can't find it, here is an extract -
The MEL does not include items such as wings, engines and landing gear that are always required, nor is reference made to equipment such as passenger convenience and entertainment items which when inoperative obviously do not affect airworthiness. It is important to note therefore that ANY ITEM WHICH IS RELATED TO THE AIRWORTHINESS OF THE AIRCRAFT AND WHICH IS NOT INCLUDED IN THE MEL IS ALWAYS REQUIRED TO BE OPERATIVE BEFORE A FLIGHT IS DISPATCHED. Likewise items required which are by Air Navigation Legislation. Additional Certification Requirements as appropriate, which are not listed, must be operative.
The important statement from the UK CAA there is
ANY ITEM WHICH IS RELATED TO THE AIRWORTHINESS OF THE AIRCRAFT AND WHICH IS NOT INCLUDED IN THE MEL IS ALWAYS REQUIRED TO BE OPERATIVE BEFORE A FLIGHT IS DISPATCHED
quite sensible, conversly the staement also means that if it's not in the MEL and IT does NOT affect The Airworthiness of the Aircraft thwn it is not required to be in the MEL. Therefore it is quite acceptable to defer the frayed carpet....etc.

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Old 16th Nov 2004, 19:02
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It is always amazing to engineers how many items fail on final approach to the home field.
regards
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Old 16th Nov 2004, 19:06
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@steamhead

It's just a matter how you flip the coin....

regards
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Old 16th Nov 2004, 21:52
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Steamhead - you're not wrong there, it's amazing how many write ups you get that are actually impossible to see from the flt deck!!!!!!!!
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Old 18th Nov 2004, 16:50
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If memory serves, the BAe ATP has two autopilots fitted and at least one HAD to be serviceable to allow any dispatch. Is this still the case ?

Believe it was...

However on the ATP, If remember correctly (Its been a few years... ) there is complication in that the Stand by control System (required for breakout or control breakage) is partly run by the Autopilot servo's.
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Old 18th Nov 2004, 18:58
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H721

Scenario 1

Under normal circumstances I would sign that one off as a non-airworthiness item. (In my company MEL Ref 05-01)

Except if it is a -400 series with vacuum toilets, in which case you need the water for toilet flushing. MEL Section 38 should sort the men from the boys on that one.

Scenario 2

The question that a certifying engineer (and a/c commander) has to ask is..WHY will the door not disarm from the outside? It maybe a symptom of a more serious problem!

I'll stick with the philosophy...If it aint in the MEL I do not sign it off.
If a Captain wants to take the a/c with an open entry in the book then that's his look out! (and more paperwork for me filling out CHIRP and MOR forms!! )

Good topic, well done all for keeping it professional without the sniping often seen on PPRUNE.
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Old 19th Nov 2004, 00:05
  #28 (permalink)  
 
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Spanners,

Rather than rubbish, your clarification re-enforces my statement, with the slight caviet that we are disscusing airworthiness related defects (I thought that was a given, but obviously not.)

You've therefore quoted chapter and verse for H721 that his Senario 1 is not airworthiness related, there fore dispatch is permissable, but senario 2 clearly is, and therefore is either covered by the MEL, or dispatch is illeagal.
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Old 19th Nov 2004, 07:23
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Cool

Wizofoz, perhaps rubbish was too strong a word - sorry, as I'm sure most will agree (maybe not) there are always grey areas in the mel, and so much depends on how the person reads it and interprets it.

So much difference can be made by the odd word and if you miss that word in your haste to get the a/c out on time (commercial pressure) it can be the difference between a goer or a stopper.

H721's examples, the door, perfectly acceptable under the mel for the 744 - quote - Door maybe inop for normal passenger loading and disembarkation provided the door is fully serviceable for emergency evacuation. There are certain maintenance checks that need to be c/o to ensure this, so perfectly acceptable.

Water (on a freighter, he's talking I think about 747) toilet water is seperate to drinking water, as long as sufficient bottled water is loaded, then not a problem.

At the end of the day I and probably most others would not release an a/c outside (or even sometimes within) the mel if it affected the airworthiness of the said a/c, I've even had the situation where (a 3rd party operator) wanted to take the a/c and we weren't prepared to release it until fixed, you have to be strong in your convictions and justified not to bow to the unnecessary and illegal pressure placed on you. (and yes we still handle them).
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Old 19th Nov 2004, 12:35
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engineer as a respected (?) profession, we are expected to provide expert advices. of course we should safeguard our bottomline, ie airworthiness, however providing solution in borderline situation is what customer wants.

my job involve substantial third party work, from their prospective, having an aircraft aog at outstation is the least thing wanted. i put forward my advice, pilot also has his/her own considerations and has every right to accept or not , no harm feeling from my side.

all airlines make safety as the paramount goal, we are part of the chain to make this happened.
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Old 22nd Nov 2004, 10:21
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H721
having an aircraft aog at outstation is the least thing wanted
I disagree H, the least thing wanted is a large pile of twisted metal and huge plume of smoke.

That's what the MEL is for. Better minds than ours have worked tirelessly and have years of experience and incidents to draw on to make it safe. No doubt they will continue to do so.

Mess with the MEL at your peril. I would rather lose a 3rd party contract than be sitting in front of the beak (Judge) with a manslaughter charge and the deaths of several hundred people hanginging over me.

OK
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Old 22nd Nov 2004, 15:54
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we engineers are being paid for making professional judgement. after spending years in this industry we should have the instinct about whatz go / no go.

i never hinted to dispatch any failed item that is n installed / n required listed in the MEL. what i meant is if something not listed in the MEL then it comes to our judgement to decide go / no go. put forward options to pilot/airlines if we feel comfortably justisified.

i'm lucky the company i work for never force anybody to sign off thing no happy with him.
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Old 22nd Nov 2004, 22:54
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we engineers are being paid for making professional judgement.
Not any more!

We are now paid to follow procedures and to ensure procedures are followed.

It's the JAA/EASA way.

If it's not in the MEL then you need a dispensation from your maintenance control/national authority. Let's face it they get paid more than us so get on the phone and wake 'em up to earn it.
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Old 23rd Nov 2004, 03:10
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it is always we engineers who have the first hand knowledge of whatz going on in the scene. depends on how well we know the aircraft/systems then we put forward options. if things no acceptable to us, ring the maintrol guys.

how to distinguish newbie or experienced engineers is the way they handle trying situations, hence using their professional knowledge. if one has to use cell phone all the time, then we all know who he /she is.

In engineering, knowledge prevails. If we have confidence of what we are doing, stand on our feet.

Whatz most most important is safety , best accompanied by on time performance.
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Old 23rd Nov 2004, 04:22
  #35 (permalink)  
 
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H721,

What is most important is covering your A legally.

As has been explained to you and backed up but quotes of the regulations, any airworthiness related failure not covered by the MEL is no-dispatch.

If you do, you are breaking the rules and leaving yourself wide open should there be an incident.
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Old 23rd Nov 2004, 08:36
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I would never let my ssa exposed.

I would neither never let an unairworthy aircraft go.

What is the last time you dispatch an aircraft with a deferred item like '1 fastener loose from body fairing xxx, speed tape applied. security checked ok'. Can you tell if this is airworthiness related? I don't see any MEL/AMM covered such but obviously this is acceptable.

If after years of practice an engineer can't judge airworthiness/non-airworthiness, I am saddened.

".....breaking the rules and leaving yourself wide open should there be an incident.'

It would only be 100% sure myself it is safe otherwise I won't exercise my authority.

From my previous postings I never have the slightest hint to voilate airthworthiness. That is the bottom line.

What I am telling is to use our professional knowledge during trying situations. If things go beyond the bottom line, don't sign.
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Old 23rd Nov 2004, 10:23
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What is the last time you dispatch an aircraft with a deferred item like '1 fastener loose from body fairing xxx, speed tape applied.
I used to do it all the time. Not any more. If I do it now I WILL get my authorisation revoked.



If after years of practice an engineer can't judge airworthiness/non-airworthiness, I am saddened.
Now you're getting it.

Certainly, in the UK, many of the 'privelages' of a Licensed Engineer have been removed. It may not have reached your neck of the woods yet, but it will.
You do it by the book or not at all, and damn the financial consequences. I have had too many interviews with quality departments to risk my livelyhood further.
If quality say you can't sign for it that is it. Time to head back to the crew room for a brew while our "betters" exercise their judgement!
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Old 23rd Nov 2004, 11:21
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I used to do it all the time. Not any more. If I do it now I WILL get my authorisation revoked.

your quality system then will be by far the superior of all in the globe.

another quick question, will you defer a scratched cabin trim panel?

It sounds all deferred items in your system beared MEL references/dispensations, if that is the case, the world should learn from such.

You do it by the book or not at all

I never do thing not by the book. It is only when I know whatz in the book (how the system works), then exercising professional judgement (for deferal) if deem appropriate .
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Old 23rd Nov 2004, 20:58
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another quick question, will you defer a scratched cabin trim panel?
I think we have already covered this.

Non airworthiness items such as carpets, cabin trim panels etc are deferred under MEL 05-01.

This is about the only time we now get to use discretion.
Even then one is looking over one's shoulder just in case that dodgy bit of carpet turns out to be a major trip hazard and the airline gets sued by Mrs Smith from Purley.

Nice talking to you H.

Watch your A se!
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Old 24th Nov 2004, 05:14
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nice talking to you T. I really learn from you.

Non airworthiness items such as carpets, cabin trim panels etc are deferred under MEL 05-01.

MEL 05-01 will be the best tool of all engineers then. but at the end of the day who decides what is non airworthiness items, CAA/EASA, QA or WE ENGINEERS? Who controls/monitors the use of such?

If I have to be in your system I would call AOG for a 0.5' scratch on a cabin trim, bearing in mind it is of fire suppression property.

I'm lucky here our CAD and my company's QA people are trained professional engineers. engineer talking to engineer. maybe in some part of the world these people are trained as diplomat. diplomat talking to engineer.

thanks for caring my ssa.
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