Extended full-power in small pistons

And what POH are you taking this information from? Are they the one from
Anthony's imagination?

And, what do max throttle and max RPM have to do with EGT, and what do these
have to do with CHT or engine life?

If you know the answer, give him one. Of course, there is no answer, since
his basic premise and assumptions show his ignorance about engines.

This, and any other newsgroup, are dynamic and are going where the threads
take them- they are not the Bible or the constitution- there is nothing
sacred or reverent about it, and there is no making it what you want or
think it should be.

Viperdoc wrote:
And what POH are you taking this information from? Are they the one from
Anthony's imagination?

And, what do max throttle and max RPM have to do with EGT, and what do these
have to do with CHT or engine life?

If you know the answer, give him one. Of course, there is no answer, since
his basic premise and assumptions show his ignorance about engines.

This, and any other newsgroup, are dynamic and are going where the threads
take them- they are not the Bible or the constitution- there is nothing
sacred or reverent about it, and there is no making it what you want or
think it should be.




I did not take it from any POH, I just copy/pasted what MX wrote, and in
that he doesn't say anything about RPM and throttle being related to EGT.
The RPM/Throttle and the max EGT are two separate statements.

RPMs do have something to do engine life, just try to run yours always
at 100%

Then of course you can read it the way it suit best your arguments.

I'm not trying to make this newsgroup the way i like it, but this is a
group about aviation and in general threads should be related to aviation.

Yes i see what kind of character is MX, but quite often his question and
related answers could be quite interesting for someone wanting to learn
about aviation.

It does no good to anybody to answer with insults or the usual "you
don't fly", "simboy" and so on, if not for the ego of the one trying to
come up first with a "wise" comment.

"Flydive" wrote in message
...
|
|
| I did not take it from any POH, I just copy/pasted what MX wrote, and in
| that he doesn't say anything about RPM and throttle being related to EGT.
| The RPM/Throttle and the max EGT are two separate statements.

But they are all still interrelated in reality, regardless of his question.

|
| RPMs do have something to do engine life, just try to run yours always
| at 100%
|
| Then of course you can read it the way it suit best your arguments.
|
| I'm not trying to make this newsgroup the way i like it, but this is a
| group about aviation and in general threads should be related to aviation.
|
| Yes i see what kind of character is MX, but quite often his question and
| related answers could be quite interesting for someone wanting to learn
| about aviation.

If someone else wants to know, then let someone else ask. Far too many of us
have had far too much of Mx.

|
| It does no good to anybody to answer with insults or the usual "you
| don't fly", "simboy" and so on, if not for the ego of the one trying to
| come up first with a "wise" comment.
|

If you believe that, then you need to spend a little more time trying to
rationalize with Mx. You may be an experience pilot or engineer, but this is
clearly Anthony 101 for you, and many of us have our PhD in his behavior.

Maxwell wrote:
"Flydive" wrote in message
...
|
|
| I did not take it from any POH, I just copy/pasted what MX wrote, and in
| that he doesn't say anything about RPM and throttle being related to EGT.
| The RPM/Throttle and the max EGT are two separate statements.

But they are all still interrelated in reality, regardless of his question.

Well before you were saying that RPM, throttle, and EGT were not
interrelated, now they are.(true)




|
| RPMs do have something to do engine life, just try to run yours always
| at 100%
|
| Then of course you can read it the way it suit best your arguments.
|
| I'm not trying to make this newsgroup the way i like it, but this is a
| group about aviation and in general threads should be related to aviation.
|
| Yes i see what kind of character is MX, but quite often his question and
| related answers could be quite interesting for someone wanting to learn
| about aviation.

If someone else wants to know, then let someone else ask. Far too many of us
have had far too much of Mx.

Maybe that someone didn't think about that problem, but seeing the
question he would like to know the answer



|
| It does no good to anybody to answer with insults or the usual "you
| don't fly", "simboy" and so on, if not for the ego of the one trying to
| come up first with a "wise" comment.
|

If you believe that, then you need to spend a little more time trying to
rationalize with Mx. You may be an experience pilot or engineer, but this is
clearly Anthony 101 for you, and many of us have our PhD in his behavior.

Is quite a while that I follow the NG, even if is true mostly lurking,
and I know MX and the way he behaves and I would sure not try to
rationalize with him. Still I believe that a correct answer to his
(eventually avoiding arguing his usual comeback) or anybody else
question would be more helpful to everybody than the usual name calling.

Just a thought.

Flydive wrote:

It does no good to anybody to answer with insults or the usual "you
don't fly", "simboy" and so on, if not for the ego of the one trying to
come up first with a "wise" comment.


The wise course is just to killfile the person you are arguing with because he
does not understand the first rule of trolling, response is all.

JJ

On Jan 2, 1:54 pm, Flydive wrote:

I did not take it from any POH, I just copy/pasted what MX wrote, and in
that he doesn't say anything about RPM and throttle being related to EGT.
The RPM/Throttle and the max EGT are two separate statements.

RPMs do have something to do engine life, just try to run yours always
at 100%.


Most "smaller" aircraft engines are certified to produce full
rated horsepower at full rated RPM for the full TBO of the engine.
Look up the TCDS sometime for any engine you want. See the FAA
website. If the POH specifies a five-minute limit at full throttle ort
full RPM or both, then that limit should be stuck with. If the POH
doesn't say it, then you'll likely find, in the cruise settings
charts, RPMs as high as redline and the fuel flows and airspeeds
expected for that setting. Fixed-pitch props are often designed so
that full throttle in level cruise will give redline RPM or something
very close to it. When we break in a new Lycoming, we operate it as
they say, which is with the last half-hour of the 3.5 hour flight at
redline RPM, which takes full throttle at around 5,000 feet. Sea level
will be similar, since the higher power generated there is absorbed by
the higher prop drag and thrust created.

Dan

As a few of the people who actually understand this stuff have pointed
out, continuous operation at full power does increase wear and tear.
It has little to do with EGT, because EGTs are generally quite low
under full power. A more serious issue is CHT.

A very common practice with the TCM IO520 is to leave the throttle at
full throughout the climb. This produces a good rich (cooling)
mixture and gets you up to cooler air quickly. Most pilots do reduce
RPM slightly to increase engine longevity and provide better cooling
(higher airspeeds also help here at the expense of rate of climb). A
lot of the turbo guys run 80-90% power at altitudes in the teens.

Mixture is used in cruise (and in climb) as a tool to manage CHT and
fuel consumption.

"WingFlaps" wrote in message
...
On Jan 2, 10:41 am, Mxsmanic wrote:
The POH for a number of small piston aircraft warn that high power and
prop
settings should not be used for extended periods. What counts as an
extended
period, and what happens to the engine if these recommended (or mandatory)
limits are exceeded?

TBF goes down.

Cheers

-------------

Actually, in the case of the smaller engines like the O-200 and O-325, I
would not hazard a guess about the effect on TBF; but I would certainly
expect that increased wear would decrease the TBO.

OTOH, let us not forget that this thread, like so many others, was started
by our favorite troll--who "flys" only simulations of turbojet powered
transport aircraft and sophisticated recip powered aircraft such as the
Beech Baron.

Therefore, keeping in mind that this is really a simulation, I respectfully
suggest the following: In the event that Anthony has exceeded the
manufacturer's powerplant recommendations, he should simulate the required
teardown inspection of his simulated engines by ceasing use of his simulator
for a month and further by donating two months of his gross income to the
the nearest church.

All the best.

Peter :-))))))

On Jan 2, 6:56*pm, "Peter Dohm" wrote:
"WingFlaps" wrote in message

...
On Jan 2, 10:41 am, Mxsmanic wrote:

The POH for a number of small piston aircraft warn that high power and
prop
settings should not be used for extended periods. What counts as an
extended
period, and what happens to the engine if these recommended (or mandatory)
limits are exceeded?

TBF goes down.

Cheers

-------------

Actually, in the case of the smaller engines like the O-200 and O-325, I
would not hazard a guess about the effect on TBF; but I would certainly
expect that increased wear would decrease the TBO.

OTOH, let us not forget that this thread, like so many others, was started
by our favorite troll--who "flys" only simulations of turbojet powered
transport aircraft and sophisticated recip powered aircraft such as the
Beech Baron.

Therefore, keeping in mind that this is really a simulation, I respectfully
suggest the following: *In the event that Anthony has exceeded the
manufacturer's powerplant recommendations, he should simulate the required
teardown inspection of his simulated engines by ceasing use of his simulator
for a month and further by donating two months of his gross income to the
the nearest church.

All the best.

Peter *:-))))))

Remember also we pay 100 penny dollars for 100 octane low lead, and
100 penny dollars for overhaul costs. We are very careful about how we
run our IO 360. It sees full throttle a lot, but we manage rpm and
other things to reduce our real money costs. "Balls to the wall" on
takeoff to 500 feet agl most of the time, then we manage the engine
and airspeed as condtitions dictate. We baby the engine -- no shock
heating, no shock cooling, cowl flaps and cht are part of all that.

Only in extreme conditions (carrying a load of ice, of a downdraft
comes to mind) would we be operating at anywhere near the extreme
engine limits. Gee, real pilots read the same manuals and manager
their airplanes differently.

writes:

Most "smaller" aircraft engines are certified to produce full
rated horsepower at full rated RPM for the full TBO of the engine.
Look up the TCDS sometime for any engine you want. See the FAA
website. If the POH specifies a five-minute limit at full throttle ort
full RPM or both, then that limit should be stuck with. If the POH
doesn't say it, then you'll likely find, in the cruise settings
charts, RPMs as high as redline and the fuel flows and airspeeds
expected for that setting. Fixed-pitch props are often designed so
that full throttle in level cruise will give redline RPM or something
very close to it. When we break in a new Lycoming, we operate it as
they say, which is with the last half-hour of the 3.5 hour flight at
redline RPM, which takes full throttle at around 5,000 feet. Sea level
will be similar, since the higher power generated there is absorbed by
the higher prop drag and thrust created.

Interesting.

I found the page I had looked at before, for the Bonanza. It's a chart that
shows manifold pressure (from 20 to 25.5) vs. RPM (from 1700 to 2700). On the
left side there's a shaded area that says "Not recommended for cruise power
settings." There's a bell-shaped area in the middle that says "continuous
operation at peak EGT permitted." There's a squared-off section on the right
(with 25 in. and 2500 RPM as its upper right corner) that says "Continuous
operation at EGTs hotter than 20° below peak EGT (rich side or lean side) is
not approved in this area."

First, what's the difference between "not recommended" and "not approved"? I
have the feeling that this wording is not chosen at random. What bad things
might happen in each of these areas of the chart?

Second, why would peak EGT be okay for certain pressures and RPMs, but not for
the highest combinations of RPM and pressure? If it were just an issue of
exhaust heat alone, I'd expect no distinction to be made--peak EGT would
always be okay. The fact that this isn't stated implies that peak EGT in
combination with certain pressures and RPMs implies other changes in the
engine state that are potentially bad or harmless--what might those be? Maybe
cylinder heat temperatures or something? Do aircraft normally have CHT gauges
in addition to (or in place of) EGT gauges?

Third, why doesn't the manual give a specific time limit? How long does
temporary have to be before it becomes continuous? What would be an example
of each?