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BigJoeRice 29th October 2008 16:59

Dear Windsheer,

As an A&P Mechanic who's been certifying the safety of Boeings from the 707 to the 777, I would suggest you take your "two pence" worth about engineers and .....

TURIN 29th October 2008 17:08

Big Joe,

I don't think Windshear means to offend.

On this side of the pond Mechanics are unqualified and have very little if any certification privilages.
The term Engineer or Certifying Technician is just the same as A&P Mechanic.

(Prediction- this thread now descends into a "my license is harder to get than yours" bun fight....again! :rolleyes:

Mad (Flt) Scientist 29th October 2008 17:14


Originally Posted by TURIN (Post 4491768)

Originally Posted by rainboe
Are you saying a plane is only fit to fly when an engineer gives his OK, not when I judge?

Er, well yes. :=

I'm sure it's written down somewhere...

Let me see,

ANO? God knows it's a big thick book, hard to read.

AWNs? Bit vague but it could be there somewhere.

BCARs/JARs/FARs? Probably, dunno they too are reading for insomniacs.

However, in the Tech Log there's a little box with Cetificate of Release to Service (CRS) in small print.

I've never asked a pilot for permission to sign it?

Actually, it's only fit to fly when you BOTH say so. At least in Canada ...


Part VI - General Operating and Flight Rules
Canadian Aviation Regulations 2008-1
Subpart 5 - Aircraft Requirements

Aircraft Equipment Standards and Serviceability

605.06 No person shall conduct a take-off in an aircraft, or permit another person to conduct a take-off in an aircraft in their custody and control, unless the aircraft equipment required by these Regulations

(a) meets the applicable standards of airworthiness; and

(b) is serviceable and, where required by operational circumstances, functioning, except if otherwise provided in Section 605.08, 605.09 or 605.10.
TCCA website

Per that first sentence, rainboe may not conduct a takeoff, and TURIN may not release it for him to do so, unless they are both satisfied that the aircraft is airworthy etc. The engineer can't make the pilot go fly; the pilot can't "snatch the aircraft keys out of the engineer's hand".

verticallimit 29th October 2008 17:21

Request a defect repaired
 
Should you not as a pilot request a defect repaired as soon as possible, instead of flying with the defect for a long time. :=
What if a new error occurs and this becomes much more serious because it already has a flaw in the system.

The systems on the aircraft depend on each other and multiple defects may well provide an unintended and unknown effects.

The systems on the aircraft has been designed for optimum safety, every time a system is flawed, its removes a part of safty.

I can not imagine that they will put many additional systems into the cockpit, just because you have to be able to fly for longer time without repair.

And it should be possible for both mechanic and pilot to ground the plane

Defects must be repaired as soon as possible :ok:

Mad (Flt) Scientist 29th October 2008 17:35


Originally Posted by verticallimit (Post 4491949)
What if a new error occurs and this becomes much more serious because it already has a flaw in the system.

The systems on the aircraft depend on each other and multiple defects may well provide an unintended and unknown effects.

That's why the guiding document, the Master MEL, is produced by the OEM, and is dependent upon safety analyses which mirror that for basic certification. "Next significant failure" is a key part of that assessment, and that's why some items can't go on the MEL - not because they are unsafe per se, but because they leave no redundancy for the next failure.



Originally Posted by verticallimit (Post 4491949)
The systems on the aircraft has been designed for optimum safety, every time a system is flawed, its removes a part of safty.

Actually, not true. "Optimum" safety is unattainable. You could just keep adding system redundancy until the aircraft weighed a million tons.

Aircraft are designed and certified for safety goals, expressed in the likelihood of a failure per flight hour, compared to the hazard of that failure. A "catastrophic" failure can occur no more than once per billion flight hours. But once you meet that standard, you're done.

So if I do my MMEl analysis, and I *still* meet the 1 in a billion rule - I'm good.


Originally Posted by verticallimit (Post 4491949)
I can not imagine that they will put many additional systems into the cockpit, just because you have to be able to fly for longer time without repair.

Actually, intentionally adding redundancy to improve dispatch reliability is not that uncommon. It all depends on the cost of a missed dispatch versus the cost of carrying the extra redundancy around. Sometimes it will make sense to add it, sometimes not.


Originally Posted by verticallimit (Post 4491949)
And it should be possible for both mechanic and pilot to ground the plane

Actually, neither can, they can only release it or not. If some other pilot is willing to fly, or some other engineer to sign it off ... well, ultimately there's an element of engineering judgement involved.

WindSheer 29th October 2008 19:12


Dear Windsheer,

As an A&P Mechanic who's been certifying the safety of Boeings from the 707 to the 777, I would suggest you take your "two pence" worth about engineers and ......
:O:O:O:O:O
Complete sincere 100% apologies to you my friend!
As Turin already commented, the term mechanic in the uk is used for a fairly unqualified person......changing wheels, brakes etc.
I CERTAINLY didn't mean to degrade your title!

All the best.:ok:

P.s. Consider 'two pence shoved'!

Hot 'n' High 29th October 2008 20:22

Karl B - thank you for your very helpful – and very obvious suggestion - which I never considered to my utter embarrassment. Actually, a quick phone call to “Spanners” would have solved it but peer pressure (everyone else claimed it was not a problem when I spoke to them) made me think it was me being a pathetic pilot! So that call was not made – this time! Learned a big lesson here so thank you for that!

SNS3 – I’m not quite sure where your “sexual innuendo” comment stems from, nor why I seem to have upset you so much. My point raised is that, if something is NOT clearly broken (ie covered in the MEL), how should you approach an issue when you feel something is not quite as it should be, but all the more experienced pilots in the Company who you talk to say something is fine? Fortunately, Karl Bamforth has quickly steered me in the right direction – an approach which I should have taken, and will in the future, take. I look to more experienced people like you and Karl for help so please have a think before you have a go at those less experienced than yourself! It may prevent an accident happening one day. Seriously!

All – regarding who can define when an aircraft is fit to fly or not … I believe it must start with an Engineer who will have a whole raft of things to do which are not obvious to a Pilot. This is really an “AND” gate situation in IT logic terms – both the Engineer AND the Captain must agree the aircraft is fit to fly. Both parties can deem an aircraft “unfit to fly” – and neither should be questioned in that decision, and neither can over-rule each others decision as those decisions are often based on different criteria. If one says “Go” and the other says “No”, the only way forward is not to fly until a suitable, mutually agreed way forward, has been devised – a classic example being a limitation placed on the aircraft until such time as the problem can be further investigated. Here, the MEL should define that limitation – for example, VFR flight only or whatever is laid down appropriate to the system in question. Hope this helps – and does not rile SNS3 too much! Just seen Mad Scientist’s post – so UK-wise I believe it to be the same!

BigJoeRice 29th October 2008 20:34

Windsheer.

Maneuver well executed. Thank you

BigJoeRice

SNS3Guppy 29th October 2008 22:22


I’m not quite sure where your “sexual innuendo” comment stems from,

At that point I said "Blow me! Enough is enough"! Perhaps I used some other phrase other than "Blow me" - but I was a tad stressed at the time!

regarding who can define when an aircraft is fit to fly or not … I believe it must start with an Engineer who will have a whole raft of things to do which are not obvious to a Pilot.
As a pilot I disagree with that statement. As a mechanic---what some of you call an "engineer," I disagree with that statement.

An inoperative, or "defective" component is located. It's referenced in the fault manual or MEL. A determination is made as to whether it's acceptable for flight or not. It's handled accordingly. Very simple. Not exactly rocket science. There's plenty that a pilot has to consider that isn't on the "engineer's raft." Certainly a MEL item may require maintenance action, but it's not the mechanic's call as to whether the pilot will fly with that condition or not. That responsibility, and that right, sits squarely in the lap of the pilot.


Should you not as a pilot request a defect repaired as soon as possible, instead of flying with the defect for a long time.
What if a new error occurs and this becomes much more serious because it already has a flaw in the system.
A "defect" which has been properly deferred is no longer a "defect." It's been properly addressed. If an additional problem arises, then that problem shall be addressed in turn, on it's own merits, applicable to the conditions that exist.

Deferrable items come with specific time intervals for which deferral is allowed.

I may get in an airplane with three deferred items, and fly it on a six or eight hour leg. I get out of the airplane and go to the hotel. When next I get to the airport, a different airplane will be waiting. At some point during my typical three week tour, I'll likely get in one of the same airplanes again, and it may o rmay not have the deferral.

There will be a host of others who have seen and considered that deferral...not just me. If the airplane is properly altered and is both legal and safe, then I'm not goin to insist that the maintenance deferral interval is cut short out of an arbitrary whim. I act safely and legally, but it is not my intention nor place to dictate how the company will do business.


The systems on the aircraft has been designed for optimum safety, every time a system is flawed, its removes a part of safty.
Not at all true. We have another thread going on a similiar topic presently. This last week I climbed into an airplane in which the flight director was deferred. The autoflight system consists of an autopilot/flight director, an autothrottle, and a yaw damper. On that particular airplane, the autothrottle went unused for the duration of the flight. The flight director was hardly missed, and I spent much of the flight without the autopilot in use, including the approach and landing. Safety was in no way compromised. With one component of the autoflight system inoperative and properly deferred, a failure in another component of the system would scarcely have been missed, and certainly would not have impacted safety.

One can hardly made such a broad brush assumption that safety is impacted because a component, applicance, or part has been deferred.

On another trip, an airplane was delayed away from a maintenance base where the flight management system would normally be updated with a current data base. I arrived to pick up the airplane to find the FMS database out of date...no longer current. A deferral per the MEL was arranged, and the airplane safely, and legally flown on a trip that terminated in a maintenance base. There, the update was arranged. We were required to manually verify each waypoint as it couldn't be extracted from the database, and we flew a VHF approach on arrival...which wasn't really any different than any other day because I always verify the lat long on each waypoint against the flight plan and chart anyway. Just not a big deal.


I can not imagine that they will put many additional systems into the cockpit, just because you have to be able to fly for longer time without repair.
Irrelevant.

Systems are not put into airplanes purely as spares to be used while other systems are deferred, but that's neither here nor there. Equipment, systems, parts, applicances, etc, can be deferred. Period. When they are deferred, it's done safely and legally, and thus ends any concern regarding the matter. A function of the MEL is the establishment of time intervals for the deferral. In my experience, seldom do the deferrals go this long, but if they do, what of it? There's a reason that the item has been given these limitations, and so long as it's safe and legal, there's little argument to be made.


Defects must be repaired as soon as possible
Deferred items are not "defects," and no, they don't need to be repaired as soon as possible. They need to be repaired within the time intervals specificed for the deferred item...time intervals set forth by the manufacturer, by the governing body, and by the operator in an approved program.

Again, a known problem isn't simply let go willy-nilly. It's addressed in accordance with a well regulated and considered program of maintenance...it's not as though a deferred item is simply ignored. When a minimum equipment list or configuration deviation list program is applied to a discrepancy, then that item has been addressed by the maintenance program.

Wirelock 30th October 2008 08:20

a pilot that thinks he knows everything = a dangerous pilot
a pilot that ignores no go defect = a dangerous pilot

likewise

an engineer that thinks he knows everything = dangerous
an engineer who ignores a no go defect = an idiot.

the only thing is i honestly think that a dangerous pilot is more likely to take a no go aircraft than an engineer would be to release one

as for a pilot that doesn't want to accept an aircraft that has been released... ok explain why and if you still don't accept it... well then i'm going for coffee
as for a pilot that thinks an aircraft is servicable when its not... i park my car, tug,or anything that i can behind it so it cant depart... take the key and...... then i'm going for coffee

Wirelock 30th October 2008 21:51

so Rainboe, i ask you a simple yes or no question.
have you ever knowingly flown an aircraft with a no go item after considering it an non safety issue??

you are the only person who seems to have an agenda here.
engineers have only 1 goal in mind and that is to release an aircraft in a servicable condition.
whether the engineer signs for a daily check or an engine replacement for us it is the same... the aircraft is only released when we are sure that the work is performed correctly and aircraft fit to fly.
i congratulate you that you are able to perform a walk around check... well done. so here you go ,there is a spoiler mixer, can you please change it, rig the cables, test it and release the aircraft to service???
i get the feeling the answer is NO

vs69 30th October 2008 22:33

Rainboe: Do you mean to come across on a bit of a downer towards engineers or are you just trying to spark a lively debate? Input is always welcome from flight deck crew and can go some way towards helping rectify a problem that is not easily replicated on the ground but this can be taken too far sometimes where individuals feel they know more than the manuals, MEL, and any other approved documentation. I would imagine they are the ones that dont get invited out for beers down route........... :-)

vs69 30th October 2008 23:35

Well we do have an interest in maintaining our status and meagre (in comparison to pilots) pay in a climate where forces are at work to erode how many of us there are and how much we get paid for it, sadly this isnt helped by the lack of a solid union for engineers that is the equivalent of BALPA in terms of power and industry coverage.
I appreciate that a pilot can sign for a transit inspection and see the economic reasons for doing so, that was not why I posted before.
Ultimately we all have responsibilites to each other and there should be respect between crews and engineers (Is this not CRM?) and I feel, Mr Rainboe, that you have little respect for us spanner wielders and would be keen to find out why.
As for the downroute beer comment, not aimed at you at all but you did bite quite well!

Wirelock 31st October 2008 01:22

Tell me you're kidding, eh? I have the MEL for guidance as well as my own judgement. Are you saying a plane is only fit to fly when an engineer gives his OK, not when I judge?
:= sorry Mr rainboe, again engineers use manuals not judgement... you might have a look in your cockpit for an AMM the next time you use your judgement, you will probably find that in some cases your judgement is wrong.
you think you know, but in fact you are guessing whatever way you put it!!

as for the comment about spoiler mixers... engineers have alot more to worry about than doing transit checks. I´d hate to have to be going to an aircraft doing a transit check about 50 times in a shift. as for an outstation, if there is an engineer there, maybe it is the only thing he gets to do all day.

i had a classic example 2 days ago , when i met a pilot on nightstop who told me that they had a leaking brake...they had returned to home base in this condition... which when i checked the leak was out of limits. the pilot thoughtit would be ok... well it was but if there had been a different senario then maybe they are dealing with a brake and wheel fire.

i have a good relationship with the pilots in my company but having read your posts and those of sns guppy it leads me to believe that some pilots do there own thing nevermind the potential consequences

lomapaseo 31st October 2008 03:05

I thought that this thread had reached its zenith about a page back with the post by Mad (Flt) Scientist

It certainly does not gain by personalizing it to a "them and us" state of mind of who is in charge.

You can bet that following a related accident the investigation will be examining very closely the work responsibilities involved and the enviornment that they were carried out within.

john_tullamarine 31st October 2008 03:43

The decision should never be one taken by one person (group) in isolation. Fitness to fly is the end product of the efforts of a number of groups -

(a) the OEM/regulatory design engineers, flight test personnel, certification folk and ICA groups .. etc

(b) the MMEL/MEL stakeholders

(c) the operator's tech services group, maintainers and aircrew/cabin crew

In respect of maintainers and aircrew, the maintainer (and this includes a pilot exercising an MA away from home base) has to release the aircraft before the pilot gets to consider the matter. The pilot, then, is the final link in the safety chain and ought not to just accept a snag deferral unless he/she has assessed all the operational matters which might impinge on the particular snag for this particular flight ... on most occasions, the MEL write-off is accepted and the flight proceeds. On some occasions, however, the pilot will decline the flight on the basis of some rational operational assessment.

Swedish Steve 31st October 2008 11:45


Engineers on this thread do have one goal in mind- engineering presence for every departure, not primarily for safety reasons, but industrial.
Well I for one hate transit checks. Nothing so boring as wandering around an aircraft and finding nothing wrong. Luckily my airline lets the crew do the transits, then they call me out if they need help. So I sell my services to other airlines to make some money for the airline, but am on call if required. They know I am around, and I get called out to around one transit in ten.

airsupport 31st October 2008 23:28

Not everything is so black and white, IF an aircraft has a toilet U/S for instance, it IS a defect so technically any Pilots flying that aircraft ARE flying a "defective" aircraft, but obvious safety is not compromised.

It ONLY ever becomes a problem if Pilots push the limits of the MELs in order to get home on time, there must be some commonsense involved here.

I have seen this all my 40 years in the Industry, and have even done this myself, I helped Pilots ferry (no pax) an F27 aircraft from Australia to England years ago, a trip of some 10 days and not one defect in the log books until we were on finals into Norwich when I wrote up 3 pages of defects. ;)

By the way, everywhere I have ever worked the Captain can always over ride an MEL and refuse to take the aircraft, but he must have a VERY good reason and be prepared to explain his reason to the chief Pilot and Company.

Jumbo Driver 1st November 2008 08:37


Originally Posted by airsupport (Post 4496506)
By the way, everywhere I have ever worked the Captain can always over ride an MEL and refuse to take the aircraft, but he must have a VERY good reason and be prepared to explain his reason to the chief Pilot and Company.

Agreed - that is of course because the final responsibility for ensuring the aircraft is serviceable before flight lies with the Commander. He can always decide, notwithstanding a defect entry that is permitted by the MEL, that he will not accept the aircraft. In particular, he is specifically required to consider, where there are multiple defects "in the book", whether the inter-related aspect of several items which in themselves are acceptable defects (ADDs), may mean that in combination they result in a non-acceptable situation that may not have been foreseen by the MEL.

What he cannot do, however, is to override the MEL requirement and fly the aircraft if the MEL says the defect is not acceptable. In this event, appropriate remedial action must be taken before flight.


JD
:)

spannersatKL 1st November 2008 08:55

Gents its not the MEL that is really in discussion, the limitations are spelt out in there (though sometimes in a wooly manner) and should be adhered to. I am thinking of the oft found damage to for example Fan Attrition Linings? There are limitations for this and some are fly on limits some are not, but the data is in the AMM Chapter 72. What does our down route pilot do about this.....say in my 'judgement' this is OK?

Or in a small island somewhere the rear fuselage gets dinged.......does he have the SRM limitations to hand?

No...can some untrained/unlicenced 'judgement' be used here? I don't think so......but sadly due to commercial pressure this is what is being done on a daily basis. It'll only end in tears!


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