CDCCL ????

[flame_bringer]

What is it basically all about , i went through the 100 pages EASA power point file course but i still didnt understand the rationale behind it ,all i understood is that it states the maintainance and insepctions procedures nessesary to ensure the flamability reduction means of the fuel tank are within tolerance and make sure that no source of arcing or sparks is around the tank .
in the power point file there is alot of info about it but it doesnt really explain what it is principally.
so can anyone explain it to me in a brief manner without going into the deep details , just a broad brush explanation .
thanks in advance

[Litebulbs]

Isn't it a system to stop navy ships from shooting down civilian passenger aeroplanes?

[MATMAX]

fb,
I think that you understood the principle already ...
This training is also to follow the rules of the SFAR 88 , JAR 25.901 , JAR 25.1309 and EASA 2006-0203 ...
By the AD EASA 2006-0203 , the FAL (Fuel Airworthiness Limitations) are mandatory.

[flame_bringer]

Ah so thats all there is to it.
In this case im pleased
Thanks alot!

[jettison valve]

I agree about the content.

What I never got, though: How can you name something "CDCCL"...??? :ugh:

And I^ll never forget these strange FAA people, talking about the "unknown unknowns" that can cause a tank to explode... :{

Cheers, J.V.

[Bus429]

The term CDCCL - Critical Design Configuration Control Limitations - actually refers to design characteristics that have to be retained during maintenance or modification. This means that disturbing systems related to, adjacent to or having a potential impact on fuel systems identified as being at risk (as identified during the accomplishment of the stipulations of SFAR 88 and related JAR or EASA documents) may be subject to special inspections identified as CDCCL tasks in ICA and in AMPs. The term Fuel Tank Safety (FTS) is more accurate with regard to training considerations and comes in two phases.

[Blacksheep]

Something the bothers me is that I have come across several cases of people resetting tripped fuel pump circuit breakers, in one case by flight crew while airborne and in two others by maintenance engineers while troubleshooting. On Boeings, the information that flight crew may not reset a tripped fuel pump circuit breaker is published in the Airplane Flight Manual. The mandatory information that "A tripped fuel pump circuit breaker may not be reset until the fault that caused it to open has been positively identifed and rectified" is contained in an AWL (Airworthiness Limitation) in Section 9 of the Maintenance Planning Document. Airbus publish the data in a similar manner.

Now, how many Line Engineers are familiar with the content of the MPD or even their company's AMP? And how many pilots read the AFM, as opposed to the Operations Manual?

Given that this seems to be a common occurence, should this information not be more widely available? Like, on a placard next to the CBs for instance?

[Bus429]

Absolutely, Blacksheep. As usual there are inconsistencies in promulgation, interpretation and application.

[HAWK21M]

In Mx CBs are not pulled out unless a specific AMM task requires that action.
All Mx personnell are aware of this aspect.If they were not then they dont belong in Mx.

[Hand Shandy]

CCDL , I loved this 3 hour brief telling us to follow the maintenance manual otherwise we were all naughty boys . Talk about stating the obvious.

[Bus429]

Hand,
Was it Phase 1 or 2? If they only dealt with approved data, it was deficient.

[TURIN]

In Mx CBs are not pulled out unless a specific AMM task requires that action.

Yeeeees, that is what we all do. Honest gov. :eek:

[Edgar Jessop]

In Mx CBs are not pulled out unless a specific AMM task requires that action.
All Mx personnell are aware of this aspect.If they were not then they dont belong in Mx.

Of course we are all aware of this but with time pressures and people prepared to use "experience/professional judgement" deviations from the manual do occur and can have terrible consequences.

Example: the Helios flight where an O2 select switch had been left in mx mode instead of flight auto.

Example: SA carrier where CBs were pulled different to manual recommendations, then left pulled, resulting in 4 engine flame out (fortunately on ground).

It's ironic that in a job that really does require experience and professional judgement, using it can be fraught with dangers.

[rclub24]

Just completed CDCCL Phase 2 today, interesting enough and only highlights the fact that norms have become commonplace within the industry.

has anyone had to do an exam at the end?

we had one, but it was fairly easy.

[Bus429]

The regs require an exam; while I give an exam for my own courses, those I deliver for third parties do not have an exam.

[skylark1532]

Mate; I think you are confused here... the guy was not talking about pulling circuit breakers in maintenance. He was talking about resetting a tripped circuit breaker that tripped during operation without satisfactory troubleshooting as to the cause. This is very dangerous in the case of a tripped fuel pump CB. CB's trip in operation for a reason. That may include arcing or high resistance at electrical connections, overload of the pump and other nasty reasons. Forcing the operation of a defective fuel pump by resetting CBs without investigating and finding the cause can cause catastrophic failure of the airframe in flight. We have seen this occur. Don't do it.
Similarly, forcing the operation of the fuel pump in maintenance is dangerous if the fuel pump is located within a volatile environment such as a fuel tank (which it usually is).
I do agree that promulgation of this information and for that matter a lot of other critical airworthiness information could be improved. The operator should ensure that all airworthiness information critical to safe operation of the aircraft is available to the aircrew; and the person responsible for continuing airworthiness of an aircraft (usually the operator) should ensure that all personnel involved in maintenance on the aircraft have access to all relevant instructions for continuing airworthiness.

[HAWK21M]

I Agree to the idea of Placarding Fuel related CBs to Investigate a tripped CB reason before Resetting.

On Exams...Every Technical course attended out here ends with an Exam & requireing a pass mark of 80% before one can be issued a certificate.

[Alber Ratman]

Read up about the Helios 737 accident as well. The aircrew did not fulfil their pre flights properly and dealt with a warning alarm in a totally incorrect manner, regardless of the warning horn being tied not only to cabin altitude as well as configuration.

[Shell Management]

What was the fuel tank issue in that accident?

[Alber Ratman]

None, however it wasn't just a maintenance error that caused the accident. Just tidying up the post that it was mentioned.

Anyway, does any MRO carry out the proceedures for open tanks IAW the type AMM? Haven't seen many that do!

[skylark1532]

Anyway, does any MRO carry out the proceedures for open tanks IAW the type AMM? Haven't seen many that do!

Alber, this statement worries me. Manufacturers do not publish AMMs for fun or simply to absolve themselves of liability. MRO's are required by law to follow applicable current maintenance data or instructions for continuing airworthiness. This may be either in the form of AMM, SRM or CMM data or other applicable current data approved or deemed approved by the controlling NAA such as from the NAA itself (eg AD) or TC or STC holder (eg service bulletin or equiv) or approved modification/repair author (eg Part 21 approved mod or repair). Under the law of most countries, an MRO's capacity to alter or generate maintenance data is extremely closely controlled and requires a degree of communication with the TC holder or author of the maintenance data and the person responsible for continuing airworthiness of the aircraft, before using such data. Generally the MRO cannot just maintain the way it wants, when they want. If you as an individual working in an MRO are under pressure to bypass or ignore current approved maintenance data, I would suggest you make an anonymous report of the situation to your controlling regulatory authority.

In the particular topic for discussion, ie a defective fuel pump, the AMM's for most aircraft types do not require emptying and purging the fuel tank to replace and test the pump; this includes situations where a fuel pump circuit breaker is tripped. But in maintenance, simply resetting a fuel pump circuit breaker that has tripped during operation without any defect investigation in accordance with maintenance data, is (for some aircraft types) not only asking for trouble and just plane stupid, but illegal, such as for some aircraft types if the tank is empty or below a certain fuel level etc. This is the situation for which I may be quoted as saying "don't do it".