TBO and airworthiness

Jim Stewart wrote:
Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.

There have been articles on avweb on the subject; search there for
details.

Short answer, for Part 91, no.

--
Jim Pennino

Remove .spam.sux to reply.

Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.

"Jim Stewart" wrote in message
. ..
Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.

TBO is a manufacturers recommendation, it has noting to do w ith
airworthiness. Some aircraft are not airworthy 100 hours after TBO, while
some run well past the number.

http://www.avweb.com/news/savvyaviator/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.

On Apr 10, 9:12 pm, Jim Stewart wrote:
Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.

Assuming you can find an IA willing to sign an annual then no.

-Robert

Robert M. Gary wrote:

On Apr 10, 9:12 pm, Jim Stewart wrote:

Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.


Assuming you can find an IA willing to sign an annual then no.


Have you found that to be a problem? I haven't. My mechanic flies his
180 on pipeline patrol and is 1000 over TBO on his 470. Another friend
also flies pipeline in his PA12 and went 3600 hours before he topped it
and 7000 hours before he finally majored it, that's a lot of 100 hour
inspections.

Matt Barrow wrote:

"Jim Stewart" wrote in message
. ..

Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.


TBO is a manufacturers recommendation, it has noting to do w ith
airworthiness. Some aircraft are not airworthy 100 hours after TBO, while
some run well past the number.

http://www.avweb.com/news/savvyaviator/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.

Thanks. I really appreciate the link.

On Apr 11, 10:16 am, Newps wrote:
Robert M. Gary wrote:
On Apr 10, 9:12 pm, Jim Stewart wrote:

Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.

Assuming you can find an IA willing to sign an annual then no.

Have you found that to be a problem? I haven't. My mechanic flies his
180 on pipeline patrol and is 1000 over TBO on his 470. Another friend
also flies pipeline in his PA12 and went 3600 hours before he topped it
and 7000 hours before he finally majored it, that's a lot of 100 hour
inspections.

Yes, many IA's I've worked with refuse to sign after 200 over TBO. Its
probably a liability issue.

-robert

"Matt Barrow" wrote in message
...

"Jim Stewart" wrote in message
. ..
Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.

TBO is a manufacturers recommendation, it has noting to do w ith
airworthiness. Some aircraft are not airworthy 100 hours after TBO, while
some run well past the number.
...

So, does anyone know if TBO is based on B-10, B-50, B-90, or - what???

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

What is B-10, B50 etc?


Karl
Always top post


"Capt. Geoffrey Thorpe" The Sea Hawk at wow way d0t com wrote in message
...
"Matt Barrow" wrote in message
...

"Jim Stewart" wrote in message
. ..
Does an engine past TBO make an aircraft
non-airworthy? I can't seem to find a
straight answer on the web.

TBO is a manufacturers recommendation, it has noting to do w ith
airworthiness. Some aircraft are not airworthy 100 hours after TBO, while
some run well past the number.
...

So, does anyone know if TBO is based on B-10, B-50, B-90, or - what???

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

"karl gruber" wrote in message
...
What is B-10, B50 etc?


Karl
Always top post


B-10, B-50... are the expected hours at which 10%, 50%, etc. are expected
to fail. The "B" is from "bearing" - the orignal theorys were developed to
predict the life of ball bearings, but the termanology is now used for
everything. The Weibull distribution is usually used to "fit" durability
data and determine these values.

If TBO is B-10, then, in most cases, it would seem silly to overhaul at TBO,
if it is B-90, then it would be optimistic to expect to make TBO...

Or, TBO could be a number that some engineer pulled out of the air (to put
it politely).

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.