A340 LPSOV actuator replacement

[jettison valve]

Hi all,

I`ve got a sincere question for you guys:

Imagine you are supposed to replace a Low pressure fuel shutoff valve actuator on an A340.
Would you consult the AMM for this work? The design of the actuator and drive assembly mating surfaces looks fool proof (although it turned out that it is not in fact!), and the required torque value for the v-clamp is quoted on the clamp...
So let me ask you again: Would you check the AMM, wouldn`t you think that a number of people out there do -not- consult the AMM for this job? I am thinking about real world - not text book...!

Regards,
J.V.

[Golden Rivet]

Trying to elicit a reply to ease your guilt ? :ok:

I'm with ASFKAP on this one - will always endevour to use the correct publications until familiar with the job.

This does still have its pitfalls as the manufacturer can and does regularly change/update procedures.


GR

[Joe Bolt]

The torque value on the clamp might not be correct. The clamp could have been fitted to the aircraft, or sitting in stores for years. Airbus could have changed the required torque load during this time, as can be verified by consulting the relevant publication.

[jettison valve]

ASFKAP, Golden Rivet, and Joe Bolt,

Thanks for your comments, very much appreciated.
I`d like to believe that everyone shares your professionalism; however, I am afraid that there are some people around who work on aircraft on their own "manual" (seen it myself).

Oh, and Golden Rivet: No, I don`t try to ease my own guilt... ;-)=)

Thanks again,
J.V.

[eng123]

J.V.,do you have a story to tell with this post? If so,please enlighten us as I agree with ASKAP on this.If it was a first time job with me then I would consult the MM but if it was a job I was familiar with then I probably wouldn't.As for torque figures.....in most cases there is a torque figure quoted in the MM.In reality,it's only certain jobs [critical systems etc] that this is followed by the letter.[rightly or wrongly]

[jettison valve]

eng123,

yup, there is a story behind my question - have a look at SB A340-28-4098 (there`s most probably also one for the A330). It`s the inspection of the LPSOV drive assemblies and its actuators. One part of the inspection is to check a certain dimension on the actuator.
This one-time inspection is fine with me. What I am concerned about is how many mechanics will miss the new AMM subtask to be added in the next revision that describes the same inspection for future installation jobs. Actuators that fail this SB or AMM subtask must not be installed on the a/c - but will everybody stumble across this AMM subtask? There`ll be some who don`t look at all, and some will only look into the test/close-up section, I am afraid...

With regards to whether this is a job you are familiar with or not: All of us have changed dozens of actuators in the last months - two jettison and two xfeed valve actuators per A340 were part of an Airbus retrofit programme.

Regards,
J.V.