Is a 5000hr plane less likely to be knackered than a 1000hr one?

That has been one of my assumptions when buying mine :-)

In addition, there is the flying/maintenance balance.
If you nurture a hangar queen which fears the sunlight when taken taken out once a quarter, you are less likely to pay so much attention to details.
Although a lot of technical installations deteriorate when not in use, too.

Never mind the attitude of pushing the limits on some repairs/maintenance issues, because “it doesn’t pay” with so little flying time per year.
Seen some those when I was looking to buy. (unlikely to be the person who bought it new for preserving value, but owner no 3 or 4 may look at it differently)

I think it depends strongly how an airplane is operated and by whom.

Some maths would say that if it is flying for 100 hrs per year, which is approximately what a private plane should do in order to be cost neutral vs renting, then the math is easy:

After 30 years it’s around 3000 hrs, after 40 years 4000 hrs and after 50 years 5000 hrs. For many GA planes that is what they approximately have. Others have flown a lot more, club airplanes, e.t.c. can easily do 200 or 300 hrs per year, so a 40 year old plane will end up with 12000 hrs or more and still be a viable airframe if it has been treated with respect and given good maintenance. Mine has an average of about 90 hrs per year over it’s 52 years of life. In comparison, most airliners do a lot more than that, some fly well over 1000 hrs and end up with 30-40k hours in the same period.

On the other hand, a 1000 hr airplane which has been sitting around outside for years only doing 10-20 hrs per year will look great on paper (wow, only 1000 hrs) but in fact has been sitting around doing nothing most of the time. That is no good for the engine, no good for the airframe either.

So I’d always be very careful with what the total hours say about any airplane. It is much more important how it’s been treated. Hangared, outside, regular maintenance vs only when it falls apart it gets fixed (or not) and so on. A 50 year old top equipped and kept airframe can be a better buy than a 20 year hangar queen.

There can be advantages in buying a specialty plane (my term) versus something which is a treated as a transport device or a money making company asset. If the plane is interesting to the owner and was bought by him as a toy, it may be taken care of regardless of how much it is flown and you may get the best of both worlds. There are a lot of planes like that in my US area and they often improve in condition over calendar time. My main plane was bought with about 900 hrs flown in almost 40 years, with several periods of storage. Except for the 2 years when new and about 3 years immediately prior to my purchase it was kept in one owners home hangar, maintained pretty carefully.

If a plane gets an annual inspection every 25 hours for 40 years, I think it typically gets quite a bit of maintenance per hour, one way or another. The issue then becomes the quality of storage and corrosion/climate – which I think are predominant issues regardless of how much the plane is flown.

What I was getting at is that a 1000hr plane could have escaped maintenance but a 5000hr plane can’t have because it would have fallen apart.

Yes. But if your 5000 hour aeroplane has not received any maintenance after it’s 4000th hour than it will be exactly like the 1000 hour plane with no maintenance. Only that every part is 20 years older…

To really answer Peter’s original question one would need to have access to a comprehensive maintenance and logbook database for as many aircraft as possible. Which, for various reasons, is impossible.

what_next wrote:

Yes. But if your 5000 hour aeroplane has not received any maintenance after it’s 4000th hour than it will be exactly like the 1000 hour plane with no maintenance. Only that every part is 20 years older…

That’s true. Although probably if the plane had only one owner all the time, it is unlikely that maintenance gets significantly better or worse after the nth hour, isn’t it?

That’s true. Although probably if the plane had only one owner all the time, it is unlikely that maintenance gets significantly better or worse after the nth hour, isn’t it?

I have made the experience (especially with cars) that once somebody decides to sell it he will stop spending money on it. Let this be a problem of the next owner… Why should it be any different with aircraft?

what_next wrote:

I have made the experience (especially with cars) that once somebody decides to sell it he will stop spending money on it. Let this be a problem of the next owner… Why should it be any different with aircraft?

Yes I agree, but this would only make much of a difference when the time between decision to sell and actually selling it is very long, right? As long as you are still flying it you are probably not going to neglect it too much, for your own safety.

Than again, as a doctor I could tell you stories how some people neglect even their own bodies until limbs literally fall off, which kinda defeats my argument…