leading edge flaps

"Ed Rasimus" wrote in message
news
On Sun, 11 Jan 2004 06:05:28 -0600, "John Carrier"
wrote:

If they extend when airpressure is reduced as airspeed slows, then it
would be redundant to add "also when a certain AOA is achieved"
because that is the inevitable, inexorable, undeniable result of
slowing.

Just musing here Ed; :-))))))

I might be missing something in what you're saying about slat extension Ed,
but FWIW, although it's true that dynamic pressure will bring out an
aerodynamic LE slat as airspeed is reduced and angle of attack is increased
as the result of that slowing, the only common denominator that SHOULD be
used for an aerodynamic slat extension parameter is aoa, not airspeed! You
can pull 12 units in an A4 and get a slat extension at ANY airspeed!! Using
airspeed as the single parameter seems to me to be like using airspeed as a
stall parameter instead of aoa. (Airspeed works for stall at a specific GW
for a 1g stall, but goes to hell when you start pulling g!! The alpha units
or degrees aoa for CLmax producing that stall however, remain the same. The
same thing goes for an aerodynamic slat extension. You can extend slats in
an A4 by reducing the airspeed all right, but ONLY when you reach 12 units
aoa which works for an airspeed explanation at 1g level flight decel.
BUT!!!! You can ALSO extend the same slats at much higher airspeeds by
accelerating the airplane to 12 units. The airspeed for each extension
scenario will be quite different, but the same 12 units still apply! AOA is
the right parameter for aerodynamic slat extension, and what's used in the
test community. I have to admit though, I can't for the life of me remember
however how the Natops for the A4 presented this information :-)))

Dudley Henriques
International Fighter Pilots Fellowship
Commercial Pilot/ CFI Retired
For personal email, please replace
the z's with e's.
dhenriquesATzarthlinkDOTnzt

On Sun, 11 Jan 2004 23:36:55 GMT, "Dudley Henriques"
wrote:


"Ed Rasimus" wrote in message
news
On Sun, 11 Jan 2004 06:05:28 -0600, "John Carrier"
wrote:

If they extend when airpressure is reduced as airspeed slows, then it
would be redundant to add "also when a certain AOA is achieved"
because that is the inevitable, inexorable, undeniable result of
slowing.

Just musing here Ed; :-))))))

I might be missing something in what you're saying about slat extension Ed,
but FWIW, although it's true that dynamic pressure will bring out an
aerodynamic LE slat as airspeed is reduced and angle of attack is increased
as the result of that slowing, the only common denominator that SHOULD be
used for an aerodynamic slat extension parameter is aoa, not airspeed!

You are correct.

It's AOA, not specifically lower airspeed. They can droop under
acceleration when a design AOA is reached.

I got so wrapped up in trying to be all-encompassing while not
grabbing the tar baby that I mis-spoke.


Ed Rasimus
Fighter Pilot (USAF-Ret)
"When Thunder Rolled"
Smithsonian Institution Press
ISBN #1-58834-103-8

"Ed Rasimus" wrote in message
...
On Sun, 11 Jan 2004 23:36:55 GMT, "Dudley Henriques"
wrote:


"Ed Rasimus" wrote in message
news
On Sun, 11 Jan 2004 06:05:28 -0600, "John Carrier"
wrote:

If they extend when airpressure is reduced as airspeed slows, then it
would be redundant to add "also when a certain AOA is achieved"
because that is the inevitable, inexorable, undeniable result of
slowing.

Just musing here Ed; :-))))))

I might be missing something in what you're saying about slat extension
Ed,
but FWIW, although it's true that dynamic pressure will bring out an
aerodynamic LE slat as airspeed is reduced and angle of attack is
increased
as the result of that slowing, the only common denominator that SHOULD be
used for an aerodynamic slat extension parameter is aoa, not airspeed!

You are correct.

It's AOA, not specifically lower airspeed. They can droop under
acceleration when a design AOA is reached.

I got so wrapped up in trying to be all-encompassing while not
grabbing the tar baby that I mis-spoke.

I know the feeling. That ole' tar baby is one sticky character all right!
If you and Carrier ever manage to talk him into the back seat of a T38 for
just one flight......just ONE!!!.....I'll buy you both a case of Scotch if
you let me take him !! :-))
Dudley

"Dudley Henriques" wrote in message

snip
I know the feeling. That ole' tar baby is one sticky character all right!
If you and Carrier ever manage to talk him into the back seat of a T38 for
just one flight......just ONE!!!.....I'll buy you both a case of Scotch if
you let me take him !! :-))

Now that you mention it, we did have Servair begging us to help them
interface new digital gyros to Houston's T-38Ns, but we rejected the work;
as the CCB system is too much overhaed. we offered a Part 25 type change,
but they did not understand.

Ed Rasimus wrote:

You are correct.

It's AOA, not specifically lower airspeed. They can droop under
acceleration when a design AOA is reached.

I got so wrapped up in trying to be all-encompassing while not
grabbing the tar baby that I mis-spoke.


Ed Rasimus

A gain of several notches.
--

-Gord.

"Gord Beaman" wrote in message
...
Ed Rasimus wrote:

You are correct.

It's AOA, not specifically lower airspeed. They can droop under
acceleration when a design AOA is reached.

I got so wrapped up in trying to be all-encompassing while not
grabbing the tar baby that I mis-spoke.


Ed Rasimus

A gain of several notches.

And isn't it so much nicer to have a civil professional discussion?

From: "Tarver Engineering"


And isn't it so much nicer to have a civil professional discussion?



Yes, real civil, tarver, without you.

begin quote

We discussing the complete name of control surfaces, no matter how
heartbraking it is for you to find out just how much of an idiot you are,Dan.

I am impressed that you were not a little turd for this thread, Dan.

end quote

Dan, U. S. Air Force, retired

"John Carrier" wrote in message
...
Slats are typically UN-powered devices on the leading edge that extend
simply by the reduced dynamic pressure against them as airspeed slows.
Example would be the leading edge extensions of the F-86 and F-100.

I wouldn't agree with "typically." Aero slats also extend when a certain
AOA is achieved ... the A-4 slats would extend at approximately 12 units
AOA
(IIRC) and bringing them out symmetrically at higher airspeeds was not a
sure thing.

Grumman liked powered slats. Both the A-6 and F-14 had them.

Unlike otherers ego driven operators here, when I corrected John Carrier WRT
the areodynamics of the F-14, he just incorporated the new information into
his explaination. I found that far more impressive than The B-52
discussion, where it took a dozen threads here and in the .sci groups to get
Buff to relent.

Then of course there is Weiss and one has to wonder how smart that boy is.