It is becoming the convention to make available a full scan of the logbooks as part of a sale. There was a time missing logs was not a big deal, but today I think the discount for missing logs is starting to approach making aircraft with missing logs close to unsaleable.
I organised a pre buy on an aircraft and the owner (retired airline pilot no longer flying) assured me no missing logs. In fact he only had logs for around the last twenty years, with the first half of the history missing.
Investing in an airframe with missing logs is for the birds! If you have missing logs use the airframe until a major component is due and then you might find parting it out makes more economic sense.
I tend to agree, Robert, of course, and always warn people about this, much to the dislike of some 
but I wonder what the exposure is if you do have 20 years’ logs?
It would be an AD which was issued more than 20 years ago and which had a one-off compliance procedure which cannot be verified visually, or by trivial disassembly. There are such things e.g. the universal joints on a TB control linkage, but they can be checked visually with about half an hour’s dismantling, and the worst case compliance cost is “a few k”. The SB169 crankshaft swap is a much bigger example (a £40-50k vulnerability) and you would deffo want to see not just a one-liner logbook entry but the full work pack.
RobertL18C wrote:
I organised a pre buy on an aircraft and the owner (retired airline pilot no longer flying) assured me no missing logs. In fact he only had logs for around the last twenty years, with the first half of the history missing.
I have no doubt this is very common. Just like the ‘full service history’ for a used car turns out to mean he has the receipt for the last new tyre he bought.
I would consider the logs missing (and the aeroplane thus worthless) until I had a scanned image of them. Any statement along the lines of “I have the logs” carries no weight – they are missing until I’ve seen them.
As always, a big factor is how far you are going to travel to see this car plane. If it is 500nm+, you will end up buying it 
The overriding factor in all this – much discussed already – is how illiterate many sellers are. In some cases this is a deliberate ploy (I am this very minute talking to a chinese moulding company which has “misunderstood” something and quoted USD 0.19 for a two-part case, when actually they mean 0.19 for the top and 0.19 for the bottom! Throw in the “current political risk” and I am gonna ship the tool back to the UK, where I can get them done for about 45p) because most buyers will assume “the best”, while in other cases it will be just … illiteracy, or a total inability to take photos and PDF them, which is pretty rare these days, and with nobody around willing to help the guy.
RobertL18C wrote:
In fact he only had logs for around the last twenty years, with the first half of the history missing.
Well, if you have twenty years worth of logs, what really could have happened before that which would matter?
@Airborne_Again your faith in human nature is very touching :)
I expect this new fundamentalism on complete quality logs (the next level is parsing logs from the pencil whip annual to a professional annual), arose from the internet and GIYF.
In the case of this example the seller was Hollywood central casting bona fide: long haul now defunct famous flag carrier airline, aircraft hangared, no corrosion, etc (I think only the first part was correct)
If you know your way around the internet you can find out about pre history. The aircraft had been in an accident in its earlier life, and in the pre buy you didn’t need logs to understand repairs were of the ‘it will buff up nicely’ variety. No logs, no evidence of OEM replacement parts and correctly documented repairs. As Peter correctly states there is a range of ADs and time in service SBs which need complete logs to be verified, especially on airframe components. How do you even know AFTT without complete logs?
Airborne_Again wrote:
Well, if you have twenty years worth of logs, what really could have happened before that which would matter?
I once got +40 years old logs but I had difficulty understanding Austrian 1977 documents written in German? honestly, I got bored after two days and I decided to concentrate on the last 15 years (aircraft changed state of registry 4 times)
AD, SB and serial numbers and let your engineer look at it?
RobertL18C wrote:
your faith in human nature is very touching
Maybe. :-) What I meant is that if the aircraft has been flown and regularly maintained for 20 years (and most likely have had both engine and prop overhauls during that time), what bad things could have happened more than 20 years ago that have passed undetected since? Serious question.
Well in this case botched repairs which will require being redoing!
There are some types which like Trigger’s broom can be endlessly rebuilt and log books can in effect start from the full rebuild. Am thinking wood, fabric, tube types from J-3 through a Staggerwing to a Spitfire.
My Bolkow Junior has a missing midlife after meticulous care at an RAF base in Germany. It was abandoned in France, then extensively rebuilt. Now on an LAA Permit, which makes maintenance cheaper, allowing better maintenance. (EASA Permit until 23.59 on 31/12/20). :-)
