A340/330 Mel
 

What does your MEL say if Cargo Fire Agent (Bottle) 1 u/s ?

No cargo, no bags, no nothing...believe its checked prior to each flight.

Our MEL says:

@404 Titan

...in one or more cargo
compartments provided
associated cargo compartment is
empty or does not contain
inflammable or combustible
materials.


....Associated cargo compartment.....

That's what our MEL says as well.

So, if Agent 1 was used in Aft Cargo hold, e.g. due to false warning, Fwd Cargo can be loaded normally, right?
:ugh:

hetfield

I have reproduced the entire remarks column from our MEL for the A330 regarding the cargo fire bottles. My interpretation is that if bottle 1 (instant discharge bottle) is U/S the entire cargo fire fighting system is considered US and therefore would have to comply with the first note. If bottle 2 (slow metered bottle) was U/S I could dispatch as long as I could land within 1 hour from any point in the flight. If I want to dispatch ETOPS then both bottles must be serviceable. Remember there are only two bottles and they protect both the forward and aft cargo compartment depending which squib is pushed. If they are discharged into the aft cargo compartment for example there is nothing left to fight a second possible fire in the forward cargo compartment and vv. So in answer to your question, no you couldn’t load the forward cargo compartment unless you can comply with the first “Note”.

Yes, I know how the system works. The MEL text TMO is missleading. One could think, ok bottle 1 was used in aft CC, so let's load the fwd.......

Not if you know how the system works.

So let's wait for the next incident/accident due to misinterpretation of MEL.

Sure it was the flightcrew's fault......

hetfield

As you know there is only one pb sw for the forward and one for the aft cargo compartment. So if you pressed the aft cargo extinguisher pb sw as you have stated, the system will discharge both bottles into the associated compartment. If one of the bottles, in this case bottle one fails to fire, bottle two should still fire. The SDCU senses you have fired the aft cargo fire agents but bottle one has malfunctioned and hasn’t fired. The associated BTL 1 light would then fail to illuminate. The system is now considered INOP for the other cargo compartment despite agent still being in bottle one. In this case the forward.

While I can see where you are coming from regarding the MEL, you have just got to interpret it by what it is not saying, if you know what I mean?

404 Titan

Bottle 2 has a restrictor!

From the AOM:

"The discharge cartridge of bottle 2 comprises a flow metering system, and so fire extinguishing agent is discharged slowly into the compartment to ensure sufficient agent concentration for 120 minutes."

(Some have 240 min instead of 120 min.)

Again, if Bottle 1 inop/empty, you have no immediate fire fighting for NEITHER compartment. (Bottle 1 discharges in 60 sec).

So, "associated Compartment" like the MEL says is pure rubbish.

hetfield

I agree with you the word “associated” is a bad word. Lets just replace it with “both” which we know that is what it really means because we both know how the system works, right? Maybe it was lost in the translation from French to English, who knows?

That being said, if you comply with the first “Note”, you will be complying with the intent of the MEL.

Somehow I think we are in heated agreement, mind you I really don’t feel that heated. Relax.:ok:

No, not really.

As bottle 1 can discharge it's agent into either fwd or aft cargo, there must be a squib, pipes, wiring and associated controls for each cargo compartment. Any of these components U/S will render the fire extinguishing inoperative in the associated compartment.

Yes, that's true.

But where is the correct MEL-reference for an inop/used Bottle 1 for A330/340?

O.K. I fully agree with you.

And, I'm only heated when my girlfriend arrives:)

Hope the MEL will not become a trap for some fellows......

I don't know your MEL. If it says the same as what 404 Titan has posted, which looks as if it is straight from the MMEL, that would seem to be the correct reference. The MEL note is pretty clear.

I don't see what there is to be confused about.

@Techman

Let's assume one takes an 330/340 with a techlog entry like

"Aft Cargo Cmpt smoke warning on Grd. Aft agent discharged."

The warning turned out to be false but agent 1 was used.

One takes the now the MEL and reads

The fire extinguishing may be
inoperative in one or more cargo
compartments provided
associated cargo compartment is
empty or does not contain
inflammable or combustible
materials.

You got it?

Again, the MEL note is pretty clear. Only bottle 2 may be inoperative. So obviously bottle 1 may not. Unless the compartments are empty or does not contain inflammable or combustible materials.

As it is the bottle that is U/S, both fwd and aft compartments are obviously associated compartments.

No you're reading it wrong:eek:

It says Installed 2, Nbr reqd 1 : And that must be No1 bottle. As it says no2 bottle may be inop by inference that means No1 must be operative.

The note means that if the extinquishing system, for whatever reason in the aft cargo hold is inop it can not be used, you can only use the fwd one. But if it is because of bottle 1 discharge you're going nowhere end of story. Because bottle 1 has to be installed.:)

Yes, I'm reading it wrong. Fellows in my airline are reading it wrong as well. But I have a copy of a different A340/330 operator's MEL which says very clearly:

Agent 1 u/s,

both Cargo Compartments must be empty.

Perhaps not reading but interpretation maybe.

I think the thing here is the note - the note doesn't just refer to bottles it is cargo extinguishing! i.e. all of mel 26-23 (I think is, I was looking at our 330 MEL).

The next bit of the MEL refers to the agent bottles.

The next bit refers to squibs, and so on.

To me if the MEL says nbr installed 2, reqd 1, only agent 2 bottle may be inop (used or whatever) then no1 agents bottle must be serviceable.

It maybe worth having a chat with your maintrol, they are normally on the ball with this sort of thing as they deal with this sort of stuff all the time.

Of course we can just blame the French for writing things this way;)

No we can't. In my country (not France:)) MEL is approved by legal authorities.

That is exactly the same as the MEL note says. The MEL note just covers more failure scenarios than Bottle 1 U/S.

When comparing MELs from different companies, be aware that a MEL is a tailored document. There can be differences from company to company.

1. Sorry, I'm only a commercial pilot
2. Yes, I know

And I'm only a Flight- and Ground-Engineer.

Does your company have a MEL course? Or is it learning as you go along?

No, unfortunatly my company is a Timbutku based LCC an I have to pump up the tires before each flight.

I thought it was a reasonable question. But if that is how you want to play it then I'm out.

hetfield

Just for the record CASA don’t approve anything, they accept it. A very big difference in the legal world and all the consequences that go along with it if something should go wrong.

As far as I’m aware and Spannersatcx can verify this, the Hong Kong CAD approves all our “CX’s” manuals which in most part are a direct copy of the originals from Airbus with only minor variations because of local regulations.

Quite right, normally the aircraft manufacturer will compile an M(aster)MEL, this will be ratified by the National Authority, the CAA, HKCAD, CASA. The NAA then issues a MMEL list for a/c types.

The MMEL can be added to by the operator (with authority and ratification by the NAA) but can not be reduced in content, or the NAA.

Essentially what you should see is an MEL produced by Boeing or Airbus added to by the NAA or operator so in essence every airlines MEL should look the same except for certain peculiarities to that airline.

In HKG CX wanted to reduce the time limit for D category items, 120 day time limit to 60 days, which it did with authority and approval from the NAA. We wouldn't of been able to increase it from 120 days though as this would be a reduction of the MMEL and not an addition.

We have also where MEL's are confusing/grey! areas changed the 'notes' etc to be more explanatory.

At the end of the day if you're not happy or are confused about the MEL then you don't have to take the a/c, of course I will pass you a mobile to call the powers that be as it's now not a Tech delay but an operational one:p

Having read, used and interpreted MEL's for a number of years now, I always read it twice, looking for the and/or's/but's and maybe's, first to understand it secondly how to get around it.:ok: It's suprising what difference one little word makes.