I agree and have also previously read Mike Busch's article but question
really is whether renting an airplane and providing a flight instructor is a
commercial operation, one without Op Specs., where, presumably, the most
conservative interpretation would be applied. Do flight schools generally
have to overhaul at TBO?

Mike
MU-2



"Matt Barrow" wrote in message
...

wrote in message
news:r5dNe.22116$Rp5.7682@trnddc03...

On 18-Aug-2005, "Doug" wrote:

I am quite sure that one can offer an aircraft for hire with an
instructor under part 91 with an engine that has gone beyond TBO.


My understanding of the "official" FAA interpretation is as follows:
Renting an airplane, as opposed to chartering one, does not constitute a
commercial, "for hire" use. Hiring of a flight instructor is a separate
transaction not tied to the rental of the airplane. Therefore,
regulations
specifically governing commercial operations do not apply to airplanes
that
are rented out for instruction or for general use by pilots, regardless
of
whether dual instruction is given. Of course, if the pilot renting the
airplane is going to use it for commercial purposes then the plane must
meet
commercial use maintenance and operational regulations.

Because this interpretation is contrary to widely held belief it is not
surprising that a local FSDO would provide a different reading.

-------------------------------------
http://www.avweb.com/news/columns/187037-1.html

The Savvy Aviator #4: Debunking TBO

Engine TBO (time between overhauls) seems to be one of the most
misunderstood concepts in aviation maintenance. There are lots of
TBO-related old wives tales that are widely believed by owners and
mechanic
alike, and they can cost owners a great deal of money. Mike Busch
endeavors
to clear up these misconceptions, and explain what TBO really means.
By Mike Busch




(MYTH) "While it's true that manufacturer's TBO isn't compulsory for
non-commercial (Part 91) operators, commercial (Part 121/135) operators
are
required to overhaul an engine when it reaches TBO."

Not so. Both Lycoming and TCM publish engine TBOs in the form of
non-mandatory service bulletins. Some Part 121/135 operators have
Operations
Specifications that require them to comply with all manufacturer's service
bulletins (even non-mandatory ones), while others have Op Specs that
require
compliance only with mandatory service bulletins. Those in the latter
group
are no more obligated to comply with published TBO than are Part 91
operators. Those in the former group might theoretically be required to
overhaul at published TBO, but most such operators request TBO extensions
from their FSDO and these are routinely granted, often for as much as 50%
over the engine manufacturer's published TBO. So, in actual practice,
published TBO is hardly ever compulsory for any operators -- commercial or
non-commercial.