calendar TBO

One finds many 20+ year old aircraft advertised with engine time =
airframe time, both in the neighborhood of 1000-1600 hours. Now, it is
my undersatanding that aircraft engines have a calendar TBO as well as a
tach TBO. however, prices for these aircraft do not seem to reflect
engines that are beyond TBO. Is calendar TBO something that is generally
ignored? Should a prospective buyer make a hard negotiating point about
it?
--
Dan
C172RG at BFM

Dan Luke wrote:

Is calendar TBO something that is generally ignored?

From what I can see, it's pretty much ignored. Most owners of older aircraft to
whom I've spoken about it seemed to be unaware that there is such a thing. When
informed, the usual attitude is "Well, I'm not going to worry about it." IIRC,
it's 15 years for the Lycoming O-320 series.

Should a prospective buyer make a hard negotiating point about it?

In the current "buyer's market", you should make a negotiating point out of
anything you can. I doubt that you'll get very far with this one, though. Even
the mechanics I've spoken to about this say the time TBO isn't important.

George Patterson
Some people think they hear a call to the priesthood when what they really
hear is a tiny voice whispering "It's indoor work with no heavy lifting".

Dan Luke wrote:
One finds many 20+ year old aircraft advertised with engine time =
airframe time, both in the neighborhood of 1000-1600 hours. Now, it is
my undersatanding that aircraft engines have a calendar TBO as well as a
tach TBO. however, prices for these aircraft do not seem to reflect
engines that are beyond TBO. Is calendar TBO something that is generally
ignored?

Yes, and certainly a seller in that position is going to do his best to ignore it.

Should a prospective buyer make a hard negotiating point about it?

As a buyer, I would certainly include it in my personal calculation of what I
would pay. You're missing out on 20 years of engineering changes, for one thing.
For another, it's probably had a lot of idle time for camshaft corrosion to
get a grip.

OTOH, assuming the price is adjusted appropriately, I'd prefer to buy a plane
with a runout engine and have it overhauled on my terms.

Dave
Remove SHIRT to reply directly.

In article ,
Dan Luke wrote:
One finds many 20+ year old aircraft advertised with engine time =
airframe time, both in the neighborhood of 1000-1600 hours. Now, it is
my undersatanding that aircraft engines have a calendar TBO as well as a
tach TBO. however, prices for these aircraft do not seem to reflect
engines that are beyond TBO.

Most sellers don't factor in engine time properly. If they've never done
an overhaul (or did it 10+ years ago) they're probably not aware of the
cost. So high time engines don't get discounted like they should. Low
time engines tend to be marked up TOO much (since the owner just felt the
sting) especially since "0" time engines are suspect to a buyer so he's
not willing to pay the full markup.

The calendar overhaul times are pretty short compared to tach time for
anything but a rental/charter. You'd have to fly about 200 hours/year
to use up the tach time in the calendar time, and not many owners do
that. On the other hand you could fly it 100 hours/year (a "good" amount
for the engine) and that would take twice the calendar overhaul time.

The way I factored it in when buying was to assume that the engine I was
looking at (O-540 or IO-540) was a type that "typically" needed a top OH
sometime, and that an engine well beyond calendar overhaul would not be
worth topping.

--
Ben Jackson

http://www.ben.com/

I bought my 68 7eca a few months ago. I had looked at several aircraft.
None of the owner's I spoke to that had gone way beyond the calender time
limit were willing to concede that it was significant. I think it is
significant. I'd rather fly a 5 year old engine thats 500 hours beyond the
2000 hour recommendation than a 500 hour engine that's 20 years past the
calendar limit recommendation.

One airplane had 500 SMOH in 1968! Another was 25 years old with 1200TT but
never overhauled. I found many airplanes in the 500-1500 hour range that
hadn't been overhauled for twenty years. My plane had 500 hours since a
factory overhaul in 1998 when I bought it. I think that the limit is 12
years. Here's a link to some lycoming information I found.

http://www.lycoming.textron.com/main...imeEngine.html

Dave
1968 7ECA

"Dan Luke" wrote in message
...
One finds many 20+ year old aircraft advertised with engine time =
airframe time, both in the neighborhood of 1000-1600 hours. Now, it is
my undersatanding that aircraft engines have a calendar TBO as well as a
tach TBO. however, prices for these aircraft do not seem to reflect
engines that are beyond TBO. Is calendar TBO something that is generally
ignored? Should a prospective buyer make a hard negotiating point about
it?
--
Dan
C172RG at BFM

"Dan Luke" wrote in message ...
One finds many 20+ year old aircraft advertised with engine time =
airframe time, both in the neighborhood of 1000-1600 hours. Now, it is
my undersatanding that aircraft engines have a calendar TBO as well as a
tach TBO. however, prices for these aircraft do not seem to reflect
engines that are beyond TBO. Is calendar TBO something that is generally
ignored? Should a prospective buyer make a hard negotiating point about
it?

Lycoming says 12 years. Of course both clock and calendar TSO's are
advisory only for most of us. Believe me, my engine was last overhauled
in 1980 and even though it only had about 600 hours on it, it's history.

Of course, how it is treated: how much it is run, the condition of engine
baffleing etc... will make more of a difference than either the calender
or tach hours. Many owner-flown planes never get to tbo either way.

"Dan Luke" wrote
One finds many 20+ year old aircraft advertised with engine time =
airframe time, both in the neighborhood of 1000-1600 hours. Now, it is
my undersatanding that aircraft engines have a calendar TBO as well as a
tach TBO.

Your understanding is correct.

however, prices for these aircraft do not seem to reflect
engines that are beyond TBO.

That's simply because lots of people are either not aware of this or
don't care. Most owner-flown engines hit calendar TBO long before
hitting tach TBO. On the other hand, most owner-flown engines also
need significant engine work well short of TBO. Coincidence? I think
not.

Is calendar TBO something that is generally ignored?

Yes, but so is tach time. As long as the engine keeps making power
and the compressions are good, it will be run.

Should a prospective buyer make a hard negotiating point about it?

Won't work. Enough people don't know or don't care about the problem,
so a seller would have to be an idiot to back down.

Michael

"Dan Luke" wrote in message ...
Is calendar TBO something that is generally
ignored?

Sellers would love buyers to ingore it. Smart buyers don't. One
of the 1st questions I ask a seller after time SMOH is the date of the
last overhaul.

Should a prospective buyer make a hard negotiating point about
it?

I would. A 500 hr. engine that was overhauled 30 yrs. ago is not
worth the same amount as a 500 hr. engine overhauled last year. I
would value the former as very close to a runout. Engines that are
not flown regularly will rarely make the xxxx hr. TBO. Lycoming's TBO
estimates assume that the engine runs at least 170 hr. per year.

Last I checked, the calendar TBO for the Lyc. 4-cyl engines was 12
yrs.

John Galban=====N4BQ (PA28-180)