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DSK September 2nd 04 09:38 PM

Mark Borgerson wrote:

In any case, ALL power/speed curves seem to be asymptotic
to c (speed of light).

How's that for a 'reductio ad absurdum' argument?


Excellent. And BTW thanks, I was beginning to think that nobody around
here has a sense of humor.

DSK


Meindert Sprang September 2nd 04 10:31 PM

"Mark Borgerson" wrote in message
t...

In any case, ALL power/speed curves seem to be asymptotic
to c (speed of light).


Duh, that's only a theory. Nobody actually tested that...... :-))

Meindert



Rodney Myrvaagnes September 3rd 04 01:09 AM

On Thu, 02 Sep 2004 19:56:51 GMT, Mark Borgerson
wrote:


In any case, ALL power/speed curves seem to be asymptotic
to c (speed of light).


True enough. That is a real asymptote.




Rodney Myrvaagnes J36 Gjo/a


Does one child rape really change Strom Thurmond's lifetime record?
For better or worse?

JAXAshby September 3rd 04 04:59 AM

Until you get past Mach 1, at least! ;-) after that point,
there are some inflection points in the power/speed curve, IIRC.


no, you don't remember any such thing. unless of course you were stoned out of
your gourd in your fourth sophomore year in college.

JAXAshby September 3rd 04 05:00 AM

rod, you were doing well up until this point:

In any case, ALL power/speed curves seem to be asymptotic
to c (speed of light).


True enough. That is a real asymptote.




Rodney Myrvaagnes J36 Gjo/a


Does one child rape really change Strom Thurmond's lifetime record?
For better or worse?









Mark Borgerson September 3rd 04 04:36 PM

In article ,
says...
Until you get past Mach 1, at least! ;-) after that point,
there are some inflection points in the power/speed curve, IIRC.


no, you don't remember any such thing. unless of course you were stoned out of
your gourd in your fourth sophomore year in college.


Whoa! You must have me mixed up with someone who went to UC Berkely in
the 60's. My sophomore year was at UC Davis in '65 and we weren't
smoking much grass at all! (although there were probaby a lot of
students figuring out how to optimize the yield---Davis being a
world-class agricultural school) ;-)


As for inflection points, consult the definition at

http://www.math.com/tables/derivatives/extrema.htm

and look at the following crude graphic

*
*
*
*
P *
*
O *
*
W *
*
E
*
R *
*

************************************************** ******************
0 0.5 1.0 1.5 2.0

MACH NUMBER


There is an inflection point at about Mach 1. However there is no point
on the graph where you get an increase in speed without an increase in
power.

If you look at the engine data at
http://www.voodoo.cz/hornet/info.html

you will find that the F-18 engines develop about 14,000 pounds thrust
at full military power and 21,000 pounds at full afterburner. Yet
it takes full military power to get to mach 1, but with 50%
more power, you can end up at mach 1.8. Thus the inflection
point just past mach 1. (Like most modern military jets prior to
the F-22, the F-18 cannot sustain supersonic speeds in level flight
without afterburners.)

If you have more detailed power/speed curves for the transonic region,
feel free to post some links to enlighten us.


Mark Borgerson

JAXAshby September 4th 04 02:56 AM

mark, that ain't no asymptote.

duh.


From: Mark Borgerson
Date: 9/3/2004 11:36 AM Eastern Daylight Time
Message-id:

In article ,
says...
Until you get past Mach 1, at least! ;-) after that point,
there are some inflection points in the power/speed curve, IIRC.


no, you don't remember any such thing. unless of course you were stoned

out of
your gourd in your fourth sophomore year in college.


Whoa! You must have me mixed up with someone who went to UC Berkely in
the 60's. My sophomore year was at UC Davis in '65 and we weren't
smoking much grass at all! (although there were probaby a lot of
students figuring out how to optimize the yield---Davis being a
world-class agricultural school) ;-)


As for inflection points, consult the definition at

http://www.math.com/tables/derivatives/extrema.htm

and look at the following crude graphic

*
*
*
*
P *
*
O *
*
W *
*
E
*
R *
*

************************************************* *******************
0 0.5 1.0 1.5 2.0

MACH NUMBER


There is an inflection point at about Mach 1. However there is no point
on the graph where you get an increase in speed without an increase in
power.

If you look at the engine data at
http://www.voodoo.cz/hornet/info.html

you will find that the F-18 engines develop about 14,000 pounds thrust
at full military power and 21,000 pounds at full afterburner. Yet
it takes full military power to get to mach 1, but with 50%
more power, you can end up at mach 1.8. Thus the inflection
point just past mach 1. (Like most modern military jets prior to
the F-22, the F-18 cannot sustain supersonic speeds in level flight
without afterburners.)

If you have more detailed power/speed curves for the transonic region,
feel free to post some links to enlighten us.


Mark Borgerson









JAXAshby September 4th 04 02:57 AM

mark, the transision for sub-sonic to super-sonic is in no way related in any
way to a discussion of "hull speed" in sailboats.

duh.

From: Mark Borgerson
Date: 9/3/2004 11:36 AM Eastern Daylight Time
Message-id:

In article ,
says...
Until you get past Mach 1, at least! ;-) after that point,
there are some inflection points in the power/speed curve, IIRC.


no, you don't remember any such thing. unless of course you were stoned

out of
your gourd in your fourth sophomore year in college.


Whoa! You must have me mixed up with someone who went to UC Berkely in
the 60's. My sophomore year was at UC Davis in '65 and we weren't
smoking much grass at all! (although there were probaby a lot of
students figuring out how to optimize the yield---Davis being a
world-class agricultural school) ;-)


As for inflection points, consult the definition at

http://www.math.com/tables/derivatives/extrema.htm

and look at the following crude graphic

*
*
*
*
P *
*
O *
*
W *
*
E
*
R *
*

************************************************* *******************
0 0.5 1.0 1.5 2.0

MACH NUMBER


There is an inflection point at about Mach 1. However there is no point
on the graph where you get an increase in speed without an increase in
power.

If you look at the engine data at
http://www.voodoo.cz/hornet/info.html

you will find that the F-18 engines develop about 14,000 pounds thrust
at full military power and 21,000 pounds at full afterburner. Yet
it takes full military power to get to mach 1, but with 50%
more power, you can end up at mach 1.8. Thus the inflection
point just past mach 1. (Like most modern military jets prior to
the F-22, the F-18 cannot sustain supersonic speeds in level flight
without afterburners.)

If you have more detailed power/speed curves for the transonic region,
feel free to post some links to enlighten us.


Mark Borgerson









Mark Borgerson September 6th 04 12:59 AM

In article ,
says...
mark, that ain't no asymptote.

duh.


Duh! Perhaps you'll re-read the part below and find I never said it
was an asymptote. I said there are inflection points in the
power speed curve. The only asymptote I've mentioned is
the one at c.

Mark Borgerson



From: Mark Borgerson

Date: 9/3/2004 11:36 AM Eastern Daylight Time
Message-id:

In article ,
says...
Until you get past Mach 1, at least! ;-) after that point,
there are some inflection points in the power/speed curve, IIRC.

no, you don't remember any such thing. unless of course you were stoned

out of
your gourd in your fourth sophomore year in college.


Whoa! You must have me mixed up with someone who went to UC Berkely in
the 60's. My sophomore year was at UC Davis in '65 and we weren't
smoking much grass at all! (although there were probaby a lot of
students figuring out how to optimize the yield---Davis being a
world-class agricultural school) ;-)


As for inflection points, consult the definition at

http://www.math.com/tables/derivatives/extrema.htm

and look at the following crude graphic

*
*
*
*
P *
*
O *
*
W *
*
E
*
R *
*

************************************************* *******************
0 0.5 1.0 1.5 2.0

MACH NUMBER


There is an inflection point at about Mach 1. However there is no point
on the graph where you get an increase in speed without an increase in
power.

If you look at the engine data at
http://www.voodoo.cz/hornet/info.html

you will find that the F-18 engines develop about 14,000 pounds thrust
at full military power and 21,000 pounds at full afterburner. Yet
it takes full military power to get to mach 1, but with 50%
more power, you can end up at mach 1.8. Thus the inflection
point just past mach 1. (Like most modern military jets prior to
the F-22, the F-18 cannot sustain supersonic speeds in level flight
without afterburners.)

If you have more detailed power/speed curves for the transonic region,
feel free to post some links to enlighten us.


Mark Borgerson










Mark Borgerson September 6th 04 01:03 AM

In article ,
says...
mark, the transision for sub-sonic to super-sonic is in no way related in any
way to a discussion of "hull speed" in sailboats.



Except that both power/speed curves show inflection points, I suppose.
The change in curvature is even more pronounced as a sailboat goes
from hull speed to planing speed, though.

duh.


Sounds like the observation of someone who has lost an argument! ;-)



Mark Borgerson


From: Mark Borgerson

Date: 9/3/2004 11:36 AM Eastern Daylight Time
Message-id:

In article ,
says...
Until you get past Mach 1, at least! ;-) after that point,
there are some inflection points in the power/speed curve, IIRC.

no, you don't remember any such thing. unless of course you were stoned

out of
your gourd in your fourth sophomore year in college.


Whoa! You must have me mixed up with someone who went to UC Berkely in
the 60's. My sophomore year was at UC Davis in '65 and we weren't
smoking much grass at all! (although there were probaby a lot of
students figuring out how to optimize the yield---Davis being a
world-class agricultural school) ;-)


As for inflection points, consult the definition at

http://www.math.com/tables/derivatives/extrema.htm

and look at the following crude graphic

*
*
*
*
P *
*
O *
*
W *
*
E
*
R *
*

************************************************* *******************
0 0.5 1.0 1.5 2.0

MACH NUMBER


There is an inflection point at about Mach 1. However there is no point
on the graph where you get an increase in speed without an increase in
power.

If you look at the engine data at
http://www.voodoo.cz/hornet/info.html

you will find that the F-18 engines develop about 14,000 pounds thrust
at full military power and 21,000 pounds at full afterburner. Yet
it takes full military power to get to mach 1, but with 50%
more power, you can end up at mach 1.8. Thus the inflection
point just past mach 1. (Like most modern military jets prior to
the F-22, the F-18 cannot sustain supersonic speeds in level flight
without afterburners.)

If you have more detailed power/speed curves for the transonic region,
feel free to post some links to enlighten us.


Mark Borgerson











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