Overhaul at TBO?

[Greg Esres]

I'm curious as to the overhaul policies at flight schools or rental
outfits. Do they typically do an overhaul at TBO? Our school
supposedly had one that had 5,000 hours, though it had been topped.
Not sure if this was the one that crashed.

[Ron Natalie]

"Greg Esres" > wrote in message ...
> I'm curious as to the overhaul policies at flight schools or rental
> outfits. Do they typically do an overhaul at TBO? Our school
> supposedly had one that had 5,000 hours, though it had been topped.
> Not sure if this was the one that crashed.

Flight school use actually is quite good for exceeding TBO. Regular
use and frequent oil changes and hundred hours over very little calendar
time means your average 172 engine can still be going strong at close
to 3000 hours.

[Greg Esres]

<<Flight school use actually is quite good for exceeding TBO>>

That's my understanding, but a student of mine, an A&P, insists that
every flight school that he's worked has overhauled engines at TBO,
and he's had others confirm that with their flight operations.

I can't imagine that any flight operation would incur the added
expense if this were clearly unnecessary.

[Bob Gardner]

The PA-28s at the FBO where I spend most of my instructing time routinely
got 2500 hours out of 2000 hour engines. When mechanics see an engine every
100 hours (which ours did), they are aware of service limits.

Bob Gardner

"Greg Esres" > wrote in message
...
> <<Flight school use actually is quite good for exceeding TBO>>
>
> That's my understanding, but a student of mine, an A&P, insists that
> every flight school that he's worked has overhauled engines at TBO,
> and he's had others confirm that with their flight operations.
>
> I can't imagine that any flight operation would incur the added
> expense if this were clearly unnecessary.
>
>
>

[David Hill]

Greg Esres wrote:
> <<Flight school use actually is quite good for exceeding TBO>>
>
> That's my understanding, but a student of mine, an A&P, insists that
> every flight school that he's worked has overhauled engines at TBO,
> and he's had others confirm that with their flight operations.
>
> I can't imagine that any flight operation would incur the added
> expense if this were clearly unnecessary.

The flight school I worked at does not automatically overhaul at TBO.
As long as the oil analyses and the compression checks are good, they
keep on flying them.

--
David Hill
david at hillREMOVETHISfamily.org
Sautee-Nacoochee, GA, USA

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[EDR]

In article >, Greg Esres
> wrote:

> I'm curious as to the overhaul policies at flight schools or rental
> outfits. Do they typically do an overhaul at TBO? Our school
> supposedly had one that had 5,000 hours, though it had been topped.
> Not sure if this was the one that crashed.

I cannot imagine any business spending money unnecessisarily.
With all the interrim inspections and oil changes, the engine should
easily exceed TBO.
That bring up the question of "What is TBO?"
Every mechanic I have talked to tells me that if there is nothing in
the oil that shouldn't be out of limits with oil analysis, and the
compression is good, you can keep on going.
On the other hand, you won't find many competition nor airshow
aerobatic aircraft that go beyond 700 or so hours TT before some kind
of OH is necessary (1200 hr TBO engines). Constant, frequent, short
duration throttle changes, full to idle are the norm in those types of
operations. Except when being flown cross country, contest to contest,
they fly 20 minutes at a contest, 30-45 minutes in practice (how many
and how long can you pull sustained g's?).