A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Owning
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Newbie question on relationships between TT, TBO and SMOH



 
 
Thread Tools Display Modes
  #1  
Old August 1st 05, 11:32 PM
H.P.
external usenet poster
 
Posts: n/a
Default Newbie question on relationships between TT, TBO and SMOH

If a plane (C172S) has 1600 TT but is at 250 hrs SMOH on an original engine
that's spec'd for 2000hrs TBO, does this mean that the engine went in for
overhaul prematurely? For what possible reason and how would I find out?


Ads
  #2  
Old August 1st 05, 11:39 PM
Mark Hansen
external usenet poster
 
Posts: n/a
Default

On 8/1/2005 15:32, H.P. wrote:

If a plane (C172S) has 1600 TT but is at 250 hrs SMOH on an original engine
that's spec'd for 2000hrs TBO, does this mean that the engine went in for
overhaul prematurely? For what possible reason and how would I find out?



Remember that TBO is based on hours run as well as calendar time. How
long was the engine in the airplane, and what does it's manufacture
recommend for calendar time to overhaul?

--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA
  #3  
Old August 2nd 05, 12:11 AM
RST Engineering
external usenet poster
 
Posts: n/a
Default

The 172S model is a 1999-2001 model year if I'm not mistaken. 6 years (less
how long it has been since SMOH) is way below any reasonable manufacturer's
recommendations.

Jim


"Mark Hansen" wrote in message
...
On 8/1/2005 15:32, H.P. wrote:

If a plane (C172S) has 1600 TT but is at 250 hrs SMOH on an original
engine that's spec'd for 2000hrs TBO, does this mean that the engine went
in for overhaul prematurely? For what possible reason and how would I
find out?


Remember that TBO is based on hours run as well as calendar time. How
long was the engine in the airplane, and what does it's manufacture
recommend for calendar time to overhaul?

--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA



  #4  
Old August 2nd 05, 12:24 AM
Michael
external usenet poster
 
Posts: n/a
Default

If a plane (C172S) has 1600 TT but is at 250 hrs SMOH on an
original engine that's spec'd for 2000hrs TBO, does this mean that
the engine went in for overhaul prematurely?


In this case, yes.

For what possible reason and how would I find out?


For many possible reasons. It could have had a prop strike and the
owner opted to major since the insurance was paying for the teardown
and rebuild anyway. The engine could have grenaded itself (bearings or
whatever). The jugs might have worn out and the owner decided to major
rather than top because it wasn't that much more money or downtime
(which isn't true, but...) The factory might have done a ****ty job of
building the engine, and it just didn't last.

Look in the logs around the time of the overhaul and prior. Was there
airframe repair at the same time? Then it was a prop strike, or maybe
an engine failure resulting in an off-airport landing. Did the engine
have a history of replacing jugs? Maybe the owner just got fed up with
it.

Really, unless there are issues with unrepaired or improperly repaired
airframe damage, I would worry a lot more about HOW the engine was
overhauled rather than WHY.

Michael

  #5  
Old August 2nd 05, 05:33 AM
BTIZ
external usenet poster
 
Posts: n/a
Default

yes...
look in the engine log book.. sometimes a reason for overhaul is not
specifically mentioned..
but information like declining compression readings etc may yield and answer
or something like "engine overhauled at xxxhours due to propeller strike,
crank passed inspection"

BT


"H.P." wrote in message
. ..
If a plane (C172S) has 1600 TT but is at 250 hrs SMOH on an original
engine that's spec'd for 2000hrs TBO, does this mean that the engine went
in for overhaul prematurely? For what possible reason and how would I
find out?



  #6  
Old August 2nd 05, 02:51 PM
Dave Butler
external usenet poster
 
Posts: n/a
Default

H.P. wrote:
If a plane (C172S) has 1600 TT but is at 250 hrs SMOH on an original engine
that's spec'd for 2000hrs TBO, does this mean that the engine went in for
overhaul prematurely? For what possible reason and how would I find out?


1. Yes
2. Too many possible reasons to enumerate.
3. Ask the owner?
  #7  
Old August 2nd 05, 02:52 PM
Paul kgyy
external usenet poster
 
Posts: n/a
Default

Engines commonly do not reach TBO unless flown regularly (i.e. daily or
hourly) and properly operated. I wouldn't be concerned about an
overhaul at 1350 hrs as long as the overhaul was properly done.

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Newbie Question, really: That first flight Cecil Chapman Home Built 25 September 20th 04 05:52 AM
A question only a newbie would ask Peter Duniho Piloting 68 August 18th 04 11:54 PM
Newbie question on Rate of Climb Wright1902Glider Home Built 0 August 17th 04 03:48 PM
Newbie Question - Vacuum vs Electric Bill Denton Aerobatics 1 April 15th 04 11:30 PM
Newbie question Bill Gribble Soaring 6 November 6th 03 07:57 PM


All times are GMT +1. The time now is 12:15 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2004-2014 AviationBanter.
The comments are property of their posters.