View Full Version : Component Maint' Manual Question
23rd Mar 2009, 16:18
Can anyone advise me on the rules for using the CMM,
As a first line maintenance organisation , should we be using the CMM for some of our equipment maintenance and what level of training does one need to have in place for using the CMM as approved data in first line maintenance ( ie we do not have these components on our capability list but neither has the manufacturer of the aircraft included maintenance instructions in the aircraft maintenence manual but has instead just referred the the CMM)
Cannot find any clear guidance under EASA
Is it still the case that the CMM is only for workshop use and to refer to it , one should have this component in there Capability list.
Or, can it be used as a document or source of Approved Data for first line maintenance.
Or lastly , are the terms for the use of a CMM indicated in the introduction of each and every manual , whereby it identifies the necessary level of training for the use and approval of such manuals.
Any help or pointers to relevant references would be a great help
Thanks in Advance
Mr @ Spotty M
23rd Mar 2009, 17:22
Good luck in finding the answers.
Our QA tell us that you can you use the CMM on the line if no specialised test equipment is used. This is where the workshop comes into play with regards to specialist equipment.
However we have always said, show us where this is written and no one yet has shown us.
Some things can only be carried out by using the CMM, you find where galley repair work or even changing some vent filters in the galley is, other than the CMM.
I know for a fact that a CMR required test on the B757 flt deck door is only in the CMM.
So once again good luck.
23rd Mar 2009, 17:29
If you are going to certify a component "off wing" and issue form 1's for it, it needs to be on your capability list as your company has to be certified, equipped to a level to overhaul it and can be audited as so.
If the component is "On Wing" and what you want to do is not covered in the usual AMM, SRM, WM, SB's etc, you need to be very wary of doing it IAW a CMM, I don't think you can do this (although I can't find the leg either).
I'd always run it via the Manufacturer via Queery note and get auth from them via fax or whatever to clear your paperwork.
This kind of thing pops up with APU's and engines a lot.
23rd Mar 2009, 17:56
We've found that if it's not in your capabilities (CAME, CAMOE etc.) then you can't perform the task... Our workaround is finding some third part organisation who does, and have them carry out the work (though this probably doesn't help your specific situation)
If you obtain some sort of authorisation / NTO from the OEM, and possibly the TC holder of your aircraft to carry out specific tasks (Galleys / APUs / Airstairs etc.) then your NAA may allow you to carry out these tasks, but its probably best to square this with the relevant authority and your QA department...
Hope this helps in some way, but if your looking for some sort of quick and easy way to work to the CMM, then you may be out of luck.
23rd Mar 2009, 21:43
Thanks for the responses , as I said , sounds like a can of worms, any further info appreciatted!!!!
23rd Mar 2009, 22:50
(As long as you are not overhauling or claiming some scheduled maintenance on the component) You can use the CMM if the AMM does not cover the rectification or show the assembly and/or configuration you need to see.
You should get the OEM to okay your use of it first. (NTO or similar certificate)
However, when you have completed your task and the component is working again - you must test the component performs correctly IAW the AMM - NOT the CMM!
This method has previously been okayed by CAA surveyors
Hope this helps.
24th Mar 2009, 05:49
It should be written into either your Part 145 MOE or your procedures. If it is, it may well specify what ATA chapters and to what depth (e.g chapter 25 without use of any specialist test equipment).
You also need some means of ensuring the CMM is being kept up to date - no easy matter with so many vendors.
In a nutshell, yes you can so long as you Quality dept have written up what you can and can't do. The NAA has to approve MOE amendments so by informing them of the amendment and assuming they do not knock it back, they (the NAA) are approving your organisation to use the CMM "on aircraft".
24th Mar 2009, 11:32
The CMM is only for shop-level maintenance. However, how many AMMs refer to pax seats? Which document used for maintaining pax seats in line or base? CMM!
This has been an anomaly under Part 145, now addressed by regulation 1056/2008 - see here (http://www.easa.eu.int/ws_prod/g/doc/Regulation/reg_1056_2008/reg_1056_2008_EN.pdf). [M.A.502 (b) & (c) most pertinent to 145]. Remember, this is in the IR, so is binding under EU law. (AMCs are not and are up to Member States/regulated persons to interpret/suggest/approve)
Most of the answers below also address the issue but Sonic's point about the MOE is spot on
25th Mar 2009, 15:36
The Boeing 737 maintenance manual only refers to fitting and removing the crew seats.
If you want to change a harness a very common task you have to certify in accordance with the CMM.
A number of aircraft manufacturers refer you from the maintenance manual to the CMM.
You can sign i.a.w the CMM providing you can comply with any special provisions e.g special tooling, NDT, testing e.t.c.
Overhauling an item as opposed to repairing it is a whole different ball game.
25th Mar 2009, 19:05
I recently changed the seals in a NLG steering actuator swivel on an A330. The CMM quoted part numbers for the seals, the AMM didn't have a reference for dismantling or reassembley of the swivel. As far as I was concerned it was just basic engineering using standard torques on the retaining bolts and standard methods of replacing seals.......all covered in chapter 20. Of course the function and leak check was carried out IAW Chapter 32 of the AMM. I had no quarms whatsoever that everything I did was to the book. Now as far as taking a more complicated component apart in order to change some gizmo that I have no knowledge of what it does or how it works then that's a different matter. Use common sense but also use chapter 20.
26th Mar 2009, 12:12
Spannerhead - good points but really the stipulations of the revised regulations actually apply. If the AMM does not specify the task, it is not an on-wing task strictly under the A-rating of your AMO. If it is in the CMM, it is strictly a shop task but could be accomplished on-wing by you if agreed by Competent Authority through the MOE etc.
Not suggesting any lack of competence - :ok: - just that these days all is well until something goes wrong and the investigations start.