CHTs - What is acceptable?

"G.R. Patterson III" wrote in message ...
Steven Barnes wrote:

Our club's Skylane has one CHT gauge with a big 'ol green range & no temps
on it. Any recommendations on how to use this rather "useless" gauge?

That's what my Maule has. I just keep it in the green during climb and descent and
check it every once in a while during cruise.

George Patterson
If you want to know God's opinion of money, just look at the people
he gives it to.


All of the information most people need is available online at

http://www.airweb.faa.gov/Regulatory...e?OpenFrameSet

These are the Type Certificate Data Sheets (TCDS) for US made
airplanes, engines, propellers and appliances (equipment such as
Carbs, seat belts and so on).
Engine TCDS give CHTs and a lot of other stuff. The statement by
the engine guys that the airframe manufacturer sets CHTs is
misleading.

Dan

Dan Thomas wrote:
: http://www.airweb.faa.gov/Regulatory...e?OpenFrameSet

: These are the Type Certificate Data Sheets (TCDS) for US made
: airplanes, engines, propellers and appliances (equipment such as
: Carbs, seat belts and so on).
: Engine TCDS give CHTs and a lot of other stuff. The statement by
: the engine guys that the airframe manufacturer sets CHTs is
: misleading.

: Dan

While the TCDS might contain the max CHTs and such, many people believe that
they are insane. The metalurgical changes that occur when you run a cylinder up to
the "approved" TCDS limit of 500 degrees are significant. Remember that once a TCDS
is approved, it's basically gospel and can never be changed.... in other words, it's
guaranteed to be wrong forever.

Different airframes' engine limits shouldn't be compared directly, but I know
I would try to take the lowest of all of them as a recommendation. The guys who know
engines say that running over 400 in cruise is bad.

-Cory

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************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering Ph.D. Graduate Student *
* Virginia Polytechnic Institute and State University *
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