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Old November 18th 08, 03:54 AM posted to rec.aviation.piloting,alt.comp.freeware
Dudley Henriques[_2_]
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Default What happened to Jay?]

On Nov 18, 2:09*pm, Franklin see_REPLY-TO_header wrote:
On Tue 18 Nov08 10:20, Dudley Henriques wrote in
news:70dbc7c0-4e28-4e1b-8245-119e5428ec32
@g17g2000prg.googlegroups.com



:
On Nov 18, 12:51*pm, Franklin see_REPLY-TO_header wrote:
On Tue 18 Nov08 06:59, Dudley Henriques wrote:


On Nov 18, 7:14*am, Franklin see_REPLY-TO_header wrote:
On Mon 17 Nov08 23:30, Dudley Henriques
wrote in news:60ccd111-02f8-4eae-bb7a-582816c86b45
@v22g2000pro.googlegroups.com:


On Nov 17, 10:23*am, Payton Byrd
wrote:
[...]


You missed the term "increasing" I'm afraid. 5.5 squared is
30.5, which is fine for pure math, but not fine for a turning
F14 with a linear expanding g profile.
The 25 figure as stated in the assumption is correct within
the problem.


Fun isn't it?


Sir, please sir. The Ps value is far too low.


Good try but no cigar I'm afraid. No Ps value is possible for ANY
aircraft without the inclusion of altitude in the equation.
Ps can be positive or negative anywhere in the envelope not on
the Ps0 line for the aircraft, BUT establishing that Ps value in
any turn is directly related to the altitude where the turn
parameters are in play.


I see that now. Ok. My mistake.


I have no idea who you're trying to impress here, but you
unfortunately picked the wrong guy :-) The purpose of my work
with the Turkey was related to EM :-))


You asked a question. I thought I could answer it. I got it wrong
but I'd like another go!


You don't give altitude so I will assume it. *You made me
re-examine where I went wrong with Ps. And look up some F-14 specs.
Specific excess power Ps is delta energy with delta time.
Accounting for induced drag which the question focuses on then
(assumming weight is approx 55 klbs) at that state I say you would
get acceleration.


Going over the various possibilities it seemed (not entirely sure)
that greater thrust should encounter even greater drag and so
airspeed could fall. *Am I getting closer?


If you want to talk energy maneuverability be my guest.
Dudley Henriques


That's for a John Boyd! What a maverick. I couldn't hope to match
his stunts to highlight E-M.


Sorry for my offensive post. Things have been nuts around here
lately with all these characters and I thought you might be another
one :-)


Yes, your second try is exactly right. In the example given, if the
g is decreased the Turkey will accelerate which is the answer to the
first question, and if the g is increased, airspeed will fall victim
to drag.


Another way to present the "problem" would be as follows, only this
time including the altitude which as you have correctly surmised,
gives us a Ps figure for the F14. In our example, the Turkey is at
T- D=0 which = Ps=0 or on the Ps equals zero line for the F14.


An F14 at 420 KCAS, 15K, in a level turn at military. As the g is
increased, drag increases as it's square. At about 5.5g, induced
drag has increased by a factor of 25. At this point, T-D=0 and Ps=0..
If g is decreased the F14 will accelerate. If we pull harder,
airspeed will drop off.


Thank you for explaining your post instead of reacting to my over
aggressive response to you.
Dudley Henriques


DH, thanks for the explanation. *No problem with your hasty reaction.
Ari can be a little hasty too. *Service leaves some with PTSD and
others, like Ari, with sharpened responses.

One should not seek to blame former combatants for a normal reaction
to the abnormal circumstances they have dealt with. *Civilians devalue
quick decisive responses because many who have never seen action learn
to value politeness even if masks ineffectiveness.

In the past, Ari has given me texts on aircraft dynamics and answered
a lot of my technical questions. It's where most of my A.D. theory
comes from. *He's a good guy. *Just ignore his direct manner because
those same reflexes are what make him good in a crisis.

I looked you up. You have quite a background in E-M.

Franklin


With all the fuss that's going on in the forum these days I'm not
quite sure who Ari is or why he posts under me in such an aggressive
manner. I've just assumed he was one more of the trolls attacking me
each day or even the same one with a different handle.
As the founder of a service organization I have a great deal of
personal respect for any vet. Perhaps whatever it was that angered him
will work itself out.
I'll give it a shot anyway, on your authority :-)
Dudley Henriques