Why turbo normalizer?

"Matt Barrow" wrote in message
...

"Mike Rapoport" wrote in message
nk.net...


65% is 65%, is 65%. All equal, no harder. That is the point of turbo
norm. The engine has not got a clue how high it is. MP is the same at
sea
level or 15 thousand.

The only argument is the temp. Keep it cool. it is not that hard, nor
is
it rocket science.
--
Jim in NC


Yes the MP is the same but the CHTs will be much higher. Basically you
are
trading better performance for higher temps. Turbo Lances can't make 75%
power above 16,000 on warm days without CHTs well over 400F. It really
isn't possible to produce a lot of power at high altitude without higher
temps. I think that Robert's point is that there is a tradeoff.

Well, it's wrong. My CHT's are virtually the same (370-380) at 8000 as
they
are at 16K.

Heat come from your mixture, and at higher altitude, there is less drag to
be overcome.

--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO


All things being equal the temperatures will be higher at higher altitudes.
It is a simple fact that less dense air does not cool as well. I'm not sure
what you are trying to say about less drag unless it is to point out the TAS
advantage of higher altitudes.

Mike
MU-2

"Peter Duniho" wrote in message
...
"Mike Rapoport" wrote in message
ink.net...
Actually a constant speed prop converts HP into thrust about the same at
all (reasonable) altitudes. That is one of the great advantages of a CS
prop.

Really? I just assumed that with air density lower, the prop (CS or
otherwise) had less air available to move, and thus could not produce
sea-level thrust.

I guess in that case, my longer take-off runs are solely due to the higher
true speed required. Still, that's a significant effect. I just don't
want anyone thinking that a turbocharger makes high-altitude takeoffs just
like sea-level.

Pete

The CS prop simply changes its angle of attack in response to the lower
density..

Mike
MU-2

"Matt Barrow" wrote in message
...

"Robert M. Gary" wrote in message
ups.com...
But runnnig your engine at 30" at 15,000 feet is MUCH harder on the
engine than running 30" at 5,000 feet. The engine runs hotter and
harder.

(Where are you getting this information from?)



No, it isn't. MOF, it's probably easier as the air temp is colder and thus
aerodynamic cooling of the engine compartment will be more efficient.


Matt (TN Beech B36)
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO



The lower ambient temperatures don't compensate for the decreased mass flow.
Temperatures rise with altitude. It is a big issue for the preasurized
piston planes flying over FL250.

Mike
MU-2

"Newps" wrote in message
...


Mike Rapoport wrote:




I would disagree, there are a lot of reasons to buy a turbo (nomalizer or
otherwise). To fly higher, fly faster, climb much faster, takeoff
shorter (much shorter at high DA).

You also have to look at your options. I will be putting the Pponk engine
into my 182 next fall. It is 275 HP. My airplane will outperform the
Turbo 182's until the density altitude reduces my 275 HP to less than the
230 HP of the turbo engine. And since I am buying it for takeoff and
climb performance and not cruise speed I will always outperform the turbo
because my typical mountain flying mission always allows me to have more
than 230 HP available. The breakeven point is 84% power.

Agreed. The ultimate for the Helio is the 450hp Allison engine. Although
it is a turbine and therefore loses power with altitude like a normally
aspirated piston, it still have more power than a turbo normalized recip and
is significantly lighter as well.

I am somewhat surprised that you always have 84% power availible for takeoff
in the mountains.


Mike
MU-2

Mike Rapoport wrote:


I am somewhat surprised that you always have 84% power availible for takeoff
in the mountains.

I don't of course. That's the breakeven point with the turbo.

"Mike Rapoport" wrote in message
ink.net...

"Matt Barrow" wrote in message
...

"Robert M. Gary" wrote in message
ups.com...
But runnnig your engine at 30" at 15,000 feet is MUCH harder on the
engine than running 30" at 5,000 feet. The engine runs hotter and
harder.

(Where are you getting this information from?)



No, it isn't. MOF, it's probably easier as the air temp is colder and
thus
aerodynamic cooling of the engine compartment will be more efficient.


Matt (TN Beech B36)
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO



The lower ambient temperatures don't compensate for the decreased mass
flow.
Temperatures rise with altitude. It is a big issue for the preasurized
piston planes flying over FL250.

So which would provide better cooling: 8000 feet and 80 degrees, or 16000
and -20?

"Mike Rapoport" wrote in message
ink.net...

"Matt Barrow" wrote in message
...

"Mike Rapoport" wrote in message
nk.net...


65% is 65%, is 65%. All equal, no harder. That is the point of
turbo
norm. The engine has not got a clue how high it is. MP is the same
at
sea
level or 15 thousand.

The only argument is the temp. Keep it cool. it is not that hard,
nor
is
it rocket science.
--
Jim in NC


Yes the MP is the same but the CHTs will be much higher. Basically you
are
trading better performance for higher temps. Turbo Lances can't make
75%
power above 16,000 on warm days without CHTs well over 400F. It really
isn't possible to produce a lot of power at high altitude without
higher
temps. I think that Robert's point is that there is a tradeoff.

Well, it's wrong. My CHT's are virtually the same (370-380) at 8000 as
they
are at 16K.

Heat come from your mixture, and at higher altitude, there is less drag
to
be overcome.

--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO


All things being equal the temperatures will be higher at higher
altitudes.
It is a simple fact that less dense air does not cool as well.

Is there a mathematical comparison for lower temp/air density versus higher
temp/density?

I'm not sure
what you are trying to say about less drag unless it is to point out the
TAS
advantage of higher altitudes.

I was responding to the need to produce higher power versus at lower
altitude for a given speed. Properly leaned, I can get roughly the same TAS
and CHT temps at higher altitude than lower IF PROPERLY LEANED. Note the
graphs in Deakins' articles on AvWeb.

In article et, Mike Rapoport wrote:
...get somewhere for maitenance. The math works out to one hour of
maitenance/training overhead for every productive flight hour which means
the plane is effectively only half as fast. It has also pushed the
cost/effective flight hour to well over $1000.

The thing is - is there an aircraft that WON'T have that overhead that
will give you the reliability of the MU-2? Anything turbocharged/piston
is likely to need more maintenance and just as much recurrent training.

If it's not a high end pressurized turboed piston twin, you end up
stooging around at low altitude like the rest of us and that kills your
mostly all-weather capability.

--
Dylan Smith, Castletown, Isle of Man
Flying: http://www.dylansmith.net
Frontier Elite Universe: http://www.alioth.net
"Maintain thine airspeed, lest the ground come up and smite thee"

In article , Morgans wrote:
Not true, if the engine is cooled with adequite airflow.

And possibly a better cooling system.

I like flying a friend's Europa. It is turboccharged (i.e. turbo
supercharged, not turbo normalized), and has thermostatically controlled
liquid cooling, and automatic turbo control. Additionally, the constant
speed prop is set by putting the selector in 'Take off', 'Climb',
'Cruise' (you can also switch it into a simple variable pitch prop, or
make it constantly variable, or feather it).

Cruise is simply a matter of putting the prop switch into the 'Cruise'
detent and setting the MP at your desired power setting. Mixture control
is automatic, too. That's the way to fly.

I've never seen that engine run particularly hot.

--
Dylan Smith, Castletown, Isle of Man
Flying: http://www.dylansmith.net
Frontier Elite Universe: http://www.alioth.net
"Maintain thine airspeed, lest the ground come up and smite thee"

"Matt Barrow" wrote in message
...

"Mike Rapoport" wrote in message
ink.net...

"Matt Barrow" wrote in message
...

"Robert M. Gary" wrote in message
ups.com...
But runnnig your engine at 30" at 15,000 feet is MUCH harder on the
engine than running 30" at 5,000 feet. The engine runs hotter and
harder.

(Where are you getting this information from?)



No, it isn't. MOF, it's probably easier as the air temp is colder and
thus
aerodynamic cooling of the engine compartment will be more efficient.


Matt (TN Beech B36)
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO



The lower ambient temperatures don't compensate for the decreased mass
flow.
Temperatures rise with altitude. It is a big issue for the preasurized
piston planes flying over FL250.

So which would provide better cooling: 8000 feet and 80 degrees, or 16000
and -20?

What is the point supposed to be? It is never going to drop 100F in 8000'.

After fixing your numbers, the engine will run cooler at 8,000 and 100F than
at 16,000' 60F.

Mike
MU-2