Just been reading the Sep 2022 issue of the US AOPA magazine and an article by Mike Busch.
His writing is always worth reading and this time he details how even the very best shops need to be kept on a short leash, and the more diligent the shop is the more this has to be done. This is because the most diligent shops will do “everything” and you get a massive bill. In the TP/jet world (I was hangared in one such for 10 years) this is normal and e.g. the TBM MM would be followed 100%.
The root of this issue – and formalised by FAA Part 91, with some similar recent concessions in EASA-land – is that stuff which is “due” (on a calendar time or service hours time basis) does not need to be done unless required by an AD or being listed in Airworthiness Limitations (normally Chapter 1) of the MM. Yet, shops everywhere like to make a list of required actions which is liberally interspersed with “due” items. One example given was an SR22 with $20k of actions of which $18k were “due” but not needed (visual inspections performed).
It’s perhaps funny that one needs to do this with diligent shops too, and even more so, while we have so many threads dealing with shops which do only some of what they bill for.
Ultimately it comes down to communication; the biggest disasters I have heard of were due to a lack of communication between the shop and the customer. It can be the fault of either; literacy is way below 100% in this business and while we do not expect mechanics to be able to write properly (one can debate whether someone running a business should be able to read and write; a fruitless debate) we would expect an aircraft owner (of a 6 digit priced plane – he must have made the money somehow??) to be able to, but this expectation is often wrong. A lot of apparently successful people live their life on their phone, for the day, tomorrow is another day, what is email?, and everything is done with calls and whatsapp one-liners.
The default position is utterly scary: you drop the plane off, the shop is entitled to do as much work as it wants, bill it, and you have to pay that figure without a limit, and if you refuse, the shop can get a lien, while charging you hangarage (which with a “cheap” plane will consume the whole plane’s value pretty soon) and the GA world is full of thus abandoned planes. So, you must always set out in writing the limits of work to be done. Apparently in California a lien is not possible but the shop can basically prevent you flying the plane away.
The motor trade knows this principle very well; I found this out slightly painfully with a VW car body repair which was to be ~1.5k and went past 3k before – on advice from someone in the trade – I managed to cap it with an email. The crooked repairer pretended to not understand this but eventually had to cave in… walked off with 2x the money so was presumably happy.
Sometimes, the vehicle “goes missing” in the middle of the night but with aircraft this is hard to do unless parked outdoors at a farm strip 
Communicating well with your maintenance provider is the key to avoiding nasty surprises but as to it driving down your bill that is questionable.
One particular customer springs to mind, a new beancounter appeared and was looking to reduce the maintenance costs so anything that was not critical was dropped including all the preventative stuff. Their next move was to change maintenance providers and this went on until the forth new maintenance company called a halt to the cycle of neglect and they got a bill the size of the Bolivian national debt.
In the long run it would have been cheaper and less problem to stay with us but bean counters never learn.
In any case, a maintenance shop that completes any work that has not been commissioned in writing puts itself onto a slippery slope.
Just getting handed the keys (or even if having in written been ordered to complete the annual inspection) is not enough.
The shop I use does take good care of having written orders by the customer for any work they do. And in their quotation for the annual inspection, they also make it clear which items are airworthiness items and which aren’t.
they got a bill the size of the Bolivian national debt.
Clearly it depends on what it is. What was the bill for? Worn airframe parts will just keep wearing… and then somebody gets a huge bill.
Take the TB20. The MM schedules are as long as your arm, with priceless items like the 800 quid fuel filter, which absolutely never needs changing unless visual inspection shows a problem. The o-rings are changed every time, of course. If you take the plane to a normal Part M firm, they will change that filter. Most of them won’t recognise any ML concessions and if you insist they will tell you to take the plane elsewhere. In the US this is probably also the case with some shops but Part 91 is long established there.
The context of Mike Busch’s article was his Savvy maintenance advisory service which he obviously charges for. In one of the hits there there are even EASA pilots who claimed to use Savvy over here. One UK pilot who used Savvy at some point has just had his prop come right off in flight on his SR22, but Savvy or no Savvy could not have provided the spanner and split pins required to avoid that!
So one has to be intelligent about what this is applied to. As an engineer and an aircraft owner of 21 years (and participating in all maintenance) I absolutely cannot say with a straight face that every item in that list is safety critical in any way. Most of them are there because
The legal position is tricky. Admittedly aviation regs are not easy to read, and EASA ones are practically impossible to find in the first place.
I think literacy is a big thing. I know that if one approaches the average maintenance shop with something like this they will tell you to f-off, and have done so over this exact topic. Applying the stickers more than doubles the # of hours required for the altimeter check. But an appreciation of the regs requires a certain level of literacy, and most people who can’t read will not admit it and will instead go on the offensive.
Currently I am emailing with one US aviation related firm and it is obvious that at best 1/3 of those participating can read and write.
a maintenance shop that completes any work that has not been commissioned in writing puts itself onto a slippery slope.
In general that is not the legal position; they can do what they like. Well, gold plating the crankcases would be excessive but they can
and this has happened. One owner I know may yet post his story, which is quite dreadful. He packed up flying.
And in their quotation for the annual inspection, they also make it clear which items are airworthiness items and which aren’t.
That’s very good, but is optional on them.
Peter wrote:
The root of this issue – and formalised by FAA Part 91, with some similar recent concessions in EASA-land – is that stuff which is “due” (on a calendar time or service hours time basis) does not need to be done unless required by an AD or being listed in Airworthiness Limitations (normally Chapter 1) of the MM. Yet, shops everywhere like to make a list of required actions which is liberally interspersed with “due” items. One example given was an SR22 with $20k of actions of which $18k were “due” but not needed (visual inspections performed).
My CAMO has to do this, it’s their job. So before annual time, they, the maintenance shop (which are two departments of the same company) and me sit down and see what of this is mandiatory and what of this can be put “on conditon” or completely discarded under part NCO or ELA1. We then also make an outlook for what is due in the year until the next annual, so we can possibly economize on stuff which would have to be done “twice” rather than once.
Communication is everything. Have we had misunderstandings? Yes, but not on those items, but rather during the massive repair following the prop strike, and if we do have such stuff, we sit down together and sort it out. Frankly, without a shop I can trust to do that, I would not operate an airplane. Nor a car btw. Same thing.
A_and_C wrote:
One particular customer springs to mind, a new beancounter appeared and was looking to reduce the maintenance costs so anything that was not critical was dropped including all the preventative stuff. Their next move was to change maintenance providers and this went on until the forth new maintenance company called a halt to the cycle of neglect and they got a bill the size of the Bolivian national debt.
Several cases here come to mind where airplanes on Swiss register were treated like this until the FOCA threatened grounding so they transferred to N-reg after repairing what was necessary to get the export certificate. Thereafter the neglect continued until the airplanes either ended up abandoned, sold for a song or crashed due to engine or other failures. At least 2 of those I remember vividly, several of the former are still around on various sites for sale since 10 years plus.
Yes, it is necessary to keep a leach, yet it is as necessary to communicate. Shops aiming for a long time relationship will not work against a customer they value and know to be as dilligent as they are.
Peter wrote:
The default position is utterly scary: you drop the plane off, the shop is entitled to do as much work as it wants, bill it, and you have to pay that figure without a limit
We are taught on our BGA part 66 inspector courses that we may only do work on a Part 21 glider if the owner has signed a work order for the work in question. How can a maintainer of a Part 21 aeroplane treat the annual as a blank cheque? Surely the owner has to sign a work order for each item of work that the shop wants to do.
Peter wrote:
If you take the plane to a normal Part M firm, they will change that filter. Most of them won’t recognise any ML concessions and if you insist they will tell you to take the plane elsewhere. In the US this is probably also the case with some shops but Part 91 is long established there.
Peter wrote:
In general that is not the legal position; they can do what they like. Well, gold plating the crankcases would be excessive but they can
do the entire MM schedule
replace every worn part where the MM does not specify limits
replace every corroded part
I disagree on both accounts.
An annual is an inspection. Asking them to do an inspection does not give them the right to replace any parts (other than O-rings, etc.).
Of course, if the owner said “here is the airplane, give it back to me in one week, with the annual signed off, and DO NOT contact me in the meantime”, then it is arguable. But even then, doing “the whole MM” would be unnecessary for the job.
Mooney_Driver wrote:
Several cases here come to mind where airplanes on Swiss register were treated like this until the FOCA threatened grounding so they transferred to N-reg after repairing what was necessary to get the export certificate. Thereafter the neglect continued until the airplanes either ended up abandoned, sold for a song or crashed due to engine or other failures. At least 2 of those I remember vividly, several of the former are still around on various sites for sale since 10 years plus.
One can always find examples to support a theory. Yes, there are owners that risk life and limb to keep the maintenance costs cheap. But there are also examples of engine failures in Switzerland shortly after regulatory cylinder replacement that would not have been needed under FAA Part 91. Sometimes in Europe risky actions are mandated in the misconceived name of safety/caution.
boscomantico wrote:
An annual is an inspection. Asking them to do an inspection does not give them the right to replace any parts (other than O-rings, etc.).
I agree.
chflyer wrote:
But there are also examples of engine failures in Switzerland shortly after regulatory cylinder replacement that would not have been needed under FAA Part 91. Sometimes in Europe risky actions are mandated in the misconceived name of safety/caution.
Yes, I am very much aware of this and the person who lost his life too. IMHO, that whole thing, including the accident report which triggered it, is a huge scandal which should never have happened.
Also needs to be said that those who went that way do not by any measure represent the N-Reg community (apart, it worked with T7 as well for a while) but just bad examples of airplane owners, who do damage to others with what they do. Thankfully, the authorities here are also aware that these cases are a small minority and treat them accordingly (so far).
