Over Maintenance
 

This is a very interesting article on a study done in the second world war indicating that the availability of aircraft was increased if less maintenance was performed.

The Waddington Effect « Opinion Leaders

I have often wondered if part of our "aging aircraft" issue has in fact been caused by imposed over maintenance and cumulative sloppy workmanship.

It probably has its parallels in over regulation...

I'm sure many of us have spent the next 10 hours after a 100 hourly going back and forth to the LAME shop getting them to fix all the things that broke during the "inspection" !

Military requirements in a War zone in WW2 are hardly relevant to today in civil aviation.

Less spanner time would equal more flying time initially. They weren't really looking at a long airframe lifespan were they!!

Hhhmmmmm...
 

A quick review of all things maintence with my plane seems to bear this out... :eek:

I'm guessing you're a LAME, nitpicker?

Me a LAME? :D. I think you just insulted LAMEies :ok:

You can hardly compare operating under War time constraints and requirements with the modern Civilian Aviation world surely?

We maintain our fleets for safety, comfort and longevity. Three things they didn't worry about in WW2 !! :D

Many new designed aircraft have eliminated small checks. The Emb Phenom 300 for example only requires an annual or a check every 600 hours which ever comes first. Engines are basically "on condition" save life limited parts...

Ageing aircraft or "abused" aircraft can be a different thing.

..............now where did I hear in recent times that ..................these new A/C need less maintenance?................
There is merit to that old saying if it ain't broke then don't fix it!

Some maint would be a feel good procedure. You know it's be checked & then you 'feel' better, doesn't guarantee a thing!

Wmk2

Nitpicker

Actually, yes I can compare now with then, and please don't call me Shirley. :p

The intended purposes of maintenance on "our fleets" are safety and longevity. So were the purposes of maintaining the fleets in WWII. A warplane stuck on the ground due to maintenance error was of zero use, other than canibalisation ...

I'll make another guess: You're not an aircraft owner. Otherwise you might have had the pleasure of spending lots of money for the annual visit to the aviation Wally World called 'picking your aircraft up after maintenance'.

It's the fun park with everything!

There's 'hide and seek': Where did they leave tools this time? :ok:

Then there's the 'disco'. Somebody - probably the LAME's kid - twiddled every knob on every avionics system. Just like a disco, you end up half-deaf and exhausted by the time you've reset everything to where it should be. :ok:

Then there's the 'room of weird mirrors'. All of the disorientation that occurs when you look through windows with grubby engineer paw marks all over them. :ok:

My favourite is the 'ghost train': What traps have been left to jump out and scare you, this time? Will it be the injector that was clogged due to 'cleaning'? Will it be the engine monitor probe that was left disconnected? Will it be 10 degree higher CHTs due to a magneto being set using the Fred Flinstone timing kit? It's an extra thrilling ride 'cause you don't find out until you're in the air! Yaaahhhhooooo! :ok:

Creampuff, sounds like your aircraft mechanics are the same ones who work on my high performance street car :ugh:

the purpose of maintenance is to ensure that the aircraft structure remains capable at all times of supporting the design loads.

:=

You mean “a” purpose, not “the” purpose. :ok:

And the point of this thread is to discuss whether the maintenance that is carried out achieves those purposes.

There's undoubtedly a U-curve in all this: too much and too little maintenance is bad on both cost and reliability grounds. There's a body of engineering literature and some good summaries are turned up by a just bit of googling. In private aviation at least, it looks to me like we're a victim of the one size fits all approach. Does my 800 hr TT puddle-jumper, which is hangared and does 50 hr a year really need the raft of provocative maintenance it's subjected to annually? I have my doubts. Fortunately I have a good LAME who directs his attentions sensibly but, even so, it's an expensive business. I'm certainly not deluded enough to think there's a bargain-basement path to air worthiness but I'm pretty confident I'm approaching the right-hand side of the U-curve.

We have been paying public servants for 50 years or more to collect data on aircraft faults & incidents. It would seem to me that it ought to be possible to use this to refine maintenance procedures. If not, why are we doing all this reporting and employing all those people?

A favorite story is a LAME who maintained the first turbo Bonanza in Australia. DCA (as it was) didn't understand turbo's. So they mandated a 50 hour inspection. Not only did it add significant cost, but cause un-necessary deterioration to the airframe.

Other mates have antique aircraft that fly literally a handful of hours per year. Yet each year all the covers come off regardless.

Where is the demonstration that we have learned things in the last 50 years?

Dr James Reason " Managing the Risk of Organisational Accidents". p 4, 5 and a bit on pages 182-186. Then p234-235.

I think Tony Kern then takes up where James Reason leaves this book and goes on to argue for an increased focus on personal responsibility.

Or indeed causes more problems then it fixes .... I'm all for preventative maintenance, but pulling the whole aeroplane to bits every year regardless of the hours flown is excessive, regardless of the cost factor and has been a constant worry for me. Now we have the mandated Cessna SIDS program where LAME's are quoting more than the aircraft is worth, which in itself seems to just be another way of getting rid of a lot of perfectly airworthy planes.

If you can find 20 minutes to read this Queensland Coroners Report you'll realise that under-maintained is far worse than over-maintained....

http://www.courts.qld.gov.au/__data/...j-20131205.pdf

XXX whilst I concour it is a good read, it is not very relevant to the subject of this post. It is however a fairly damning picture of the problems associated with under regulation, in this case of almost everything about what not to do in aviation in the one accident.
Cheers
A172 :sad:

Thanks for your note there Chris. I'll be sure to check all of my submissions in the future to ensure that they are relevant and please all audiences.

The point is imagine if this operator decided to reduce maintenance for reliability purposes. The Gyro community is by no means under-regulated; in this case, backyard pilots and mechanics were rife, not unlike parts of the GA world in remote Australia. To suggest that maintenance could be safely reduced for operators, it's inviting issues for those taking that advice literally.