I’ve seen some awful junk in homebuilts
There is no standard, so “anything” goes. The only “standard” is “according to good aviation practice”. Which makes it as meaningful or meaningless as you want depending on how familiar you are with “good aviation practice”. Tons of books, webinars etc on the subject though.
I have seen very little junk in homebuilts. But some do modifications they obviously shouldn’t do.
My reference to a signoff being “conditional” was simply what I wrote earlier i.e. an engine done as IRAN does not imply any ADs were complied with, whereas an engine done as OH does imply that.
Admittedly anybody doing an IRAN and ignoring ADs is an idiot – looking at how many man-hours go into taking an engine to bits – and doing a huge dis-service to his customer (who is prob99 totally ignorant of what is happening) but that isn’t the point 
That said, a lot of maint companies did “somehow” forget about Lyco’s SB569 and the corresponding crankshaft AD…
I’ve seen some awful junk in homebuilts. A good area is a lack of understanding of vibration. For example any pipes or wire looms which run across the engine rubber mounts need to be flexible.
I agree with much of what Mike Busch has written, in fact I don’t know of an instance where I have disagreed.
Peter wrote:
Anyone believing that EASA regs are easy to find and understand should try his local maint company, and quote a few of them, and see how far you get
Now you’re moving the goalpost! You talked about finding, not understanding. I agree that some regs make difficult reading but in most cases it is really a case of “can’t bother to check what the regs say.”
Certification is when a third party in some way approves something according to a standard. It’s nothing more than that, but the key elements are: third party approval and existing industry standards (+ approved deviations, additions, directives etc). The only tangible output of this is records of approval. If no records of approval exists, then certification does not exists. Lack of records does not imply lack of adherence to a standard however. Lack of adherence to a standard means experimental (in aviation terms), and lack of records means not certified.
The aviation authorities are the third party. They outsource the “footwork” to individuals and organizations. Maintenance and repairs are done according to standards, and the sign off is done on behalf of the aviation authority.
Peter wrote:
There is a basic principle that previous signoffs must be accepted at face value. To do otherwise would undermine the whole certification process. But there are exceptions such as the above, when a signoff is in some way conditional.
I don’t see how that is conditional. Only an overhaul is an overhaul including whatever is implicitly included in an overhaul. The only thing of value with certification is the records because that is the only output from certification. The only person for whom these records are valuable, is the owner. The aviation authorities couldn’t care less about the records and certification in itself. The only thing of interest to them is if the aircraft is airworthy or not. Airworthiness does not imply certification. Certification is only the “stamp” they (as a third party) put on the records so that you as the owner can sleep well at night, and sell the aircraft easily at a later stage It’s the proof of airworthiness, issued by a third party, and therefore of highest value for the owner of a certified aircraft. But of course it is very much in the authorities interest that whoever actually puts that “stamp”, does so in accordance with their rules and regulations.
As time marches on, how relevant are 50-60-70 year old documents regarding certification of an aircraft today in any case? Not very I would think, not regarding airworthiness. It’s more important that it is maintained in an appropriate fashion. For the owner it could be important, or not. That’s very much up to the owner IMO. But now we are heading into the world of antiquated items, where such records takes on a new dimension of value entirely.
MedEwok wrote:
I don’t think anyone can dispute any of this with a straight face.
Certification and QA is not the same thing. QA is a much broader thing with vague definitions, certification has a very specific meaning. For an end user certification is the best thing you can hope to get (if adherence to industry standards is your definition of good) and involves much more than the vaguely defined term “quality”, while ISO 9000 is probably the worst (or completely meaningless at best. It is something however).
The question is how meaningful and important is it for a light personal aircraft to actually adhere to a standard at all. Does that make life easier for the end user, and in terms of what? Is it safer, better, faster. Will it do better loops and rolls ? Certification is certainly no prerequisite for record keeping. As far as I’m concerned the single only positive thing about certification is it puts all discussions and ponderings about airworthiness dead. As long it’s kept certified (according to regulations), it’s also airworthy, period, end of discussion. This is true also it the aircraft is otherwise an old worn out piece of junk. A non certified aircraft would have to be kept to a much higher standard if the airworthiness is to be believable, and they usually are. I have yet to see a piece of junk non certified aircraft.
I don’t agree; EASA regs are all over the place with various versions turning up online, and the really useful ones are sabotaged by the maintenance industry, while FAA ones have remained constant for decades and only the obscure areas are subject to FAA CC interpretations.
Anyone believing that EASA regs are easy to find and understand should try his local maint company, and quote a few of them, and see how far you get 
wbardorf wrote:
Agree, I personally find the EASA regs nowadays easier to find than the FAA ones, especially with the Easy Access documents which also include the GMs and AMCs. My issue with the FAA is that although the formal regs (FARs) are easily found, there are various interpretation/applications scattered across the AIM, advisory circulars and other documents.
Likewise! Easy to find anything. And especially comparing to UK CAA documentation, EASA documentation is great.
Agree, I personally find the EASA regs nowadays easier to find than the FAA ones, especially with the Easy Access documents which also include the GMs and AMCs. My issue with the FAA is that although the formal regs (FARs) are easily found, there are various interpretation/applications scattered across the AIM, advisory circulars and other documents.
Peter wrote:
Most people cannot even find the European ones!
Frankly, that would be for lack of trying. When I do a web search for “EASA regulations”, the EASA regulations web page comes at the top of my list. (And I use DuckDuckGo, not Google, so the search is not skewed due to my aviation interests.)
My observation looking at those of my own planes is that maintenance logbook entries have become ever more detailed over the years. The expectation in the past was that none of these planes would be around that long and nobody cared as much about records. Now that they have 50 years of maintenance, repairs and varied ‘history’ behind them, owners and buyers care a lot more
You should have seen some of the records in the original combined airframe, engine and flight log issued from the factory with my ex-Luscombe in 1946… For example (from memory), “Removed, overhauled and reinstalled cylinders Jonny Mechanic A&E 12345” and that was it. That plane was flown 500 hrs between March and winter that year, apparently they didn’t have time for detailed logbook entries. There was of course the classic “repaired wind damage” entry too, a little later on. I doubt they thought it would be around in another 10 years, and even less that somebody like me would be flying the plane and studying the logs 70 years later.
@planewrench my current plane is on its original 1971 engine build, so you wouldn’t have to worry about overhaul records, just oil pump AD compliance and a couple of other things that are in fact reasonably documented.
