leading edge flaps

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

BackToNormal wrote:
Tarver Engineering wrote:

"Smartace11" wrote in message
...

They can and have been actively controlled, by computers, in both
aircraft and autos.

I agree but not in F1 or F! type cars as you said. Rules don't
allow.

I wrote that there are Formula One type races for cars with computer
controlled spoiler flaps..

Nope. You specified "some formula one style racers".
*******
That's not the same as "Formula One type races" Tarver.
*****
Airflow appendages on F1 cars can not be adjusted during racing. Any
category allowing such adjustment would not be a F1 style racer.

Wrong.

Which of the following allow in-race adjustment -- F1, Champcars,
Indycars, F2000, F3000, F5000, F2, F3, F4, Barber Dodge Pro,
Formula Ford, Formula Renault, Europa Cup, Formula BMW, Formula
Holden, Formula Nippon, Formula Nissan, Formula Palmer Audi, Fran-Am
1600, Formula Russell, Formula Vee, Star Mazda, Formula F Zetec etc.

Most of those categories can have the aero package adjusted during the race,
some may even do it routinely during a pitstop like Champcars/Indycars and
to a lesser extent F1.

They are open wheelers (but so is my neighbour's quad bike).

Which of the above are F1 "style" categories?

Generally speaking F1 style categories are slicks and wings with more power
than grip.

--
James...
www.jameshart.co.uk

James Hart wrote:

BackToNormal wrote:
Tarver Engineering wrote:

"Smartace11" wrote in message
...

They can and have been actively controlled, by computers, in both
aircraft and autos.

I agree but not in F1 or F! type cars as you said. Rules don't
allow.

I wrote that there are Formula One type races for cars with computer
controlled spoiler flaps..

Nope. You specified "some formula one style racers".
*******
That's not the same as "Formula One type races" Tarver.
*****
Airflow appendages on F1 cars can not be adjusted during racing. Any
category allowing such adjustment would not be a F1 style racer.

Wrong.

Nope. You haven't quite followed the thread. Tarver wrote "they
(airflow appendages) can and have been actively controlled, by
computers, in both aircraft and autos". That obviously means while an
aircraft is flying and an auto is racing. I was referring to ON-TRACK
racing, not while the car is stationary in the pits.

Which of the following allow in-race adjustment -- F1, Champcars,
Indycars, F2000, F3000, F5000, F2, F3, F4, Barber Dodge Pro,
Formula Ford, Formula Renault, Europa Cup, Formula BMW, Formula
Holden, Formula Nippon, Formula Nissan, Formula Palmer Audi, Fran-Am
1600, Formula Russell, Formula Vee, Star Mazda, Formula F Zetec etc.

Most of those categories can have the aero package adjusted during the race,
some may even do it routinely during a pitstop like Champcars/Indycars and
to a lesser extent F1.

See above.

They are open wheelers (but so is my neighbour's quad bike).

Which of the above are F1 "style" categories?

Generally speaking F1 style categories are slicks and wings with more power
than grip.

Huh! F1 cars do NOT have slicks!

ronh


--
"People do not make decisions on facts, rather,
how they feel about the facts" Robert Consedine

BackToNormal wrote:
James Hart wrote:

BackToNormal wrote:
Tarver Engineering wrote:

"Smartace11" wrote in message
...

They can and have been actively controlled, by computers, in both
aircraft and autos.

I agree but not in F1 or F! type cars as you said. Rules don't
allow.

I wrote that there are Formula One type races for cars with
computer controlled spoiler flaps..

Nope. You specified "some formula one style racers".
*******
That's not the same as "Formula One type races" Tarver.
*****
Airflow appendages on F1 cars can not be adjusted during racing. Any
category allowing such adjustment would not be a F1 style racer.

Wrong.

Nope. You haven't quite followed the thread.

Yes I have.

Tarver wrote "they
(airflow appendages) can and have been actively controlled, by
computers, in both aircraft and autos". That obviously means while an
aircraft is flying and an auto is racing.

Correct, he did write that and what's more he's right, computer controlled
airflow appendages have been used in auto racing. These days they are mostly
banned though.

I was referring to ON-TRACK
racing, not while the car is stationary in the pits.

Then why didn't you state that then? Quote "Airflow appendages on F1 cars
can not be adjusted during racing."
Last I checked the pits are part of racing.

Which of the following allow in-race adjustment -- F1, Champcars,
Indycars, F2000, F3000, F5000, F2, F3, F4, Barber Dodge Pro,
Formula Ford, Formula Renault, Europa Cup, Formula BMW, Formula
Holden, Formula Nippon, Formula Nissan, Formula Palmer Audi, Fran-Am
1600, Formula Russell, Formula Vee, Star Mazda, Formula F Zetec etc.

Most of those categories can have the aero package adjusted during
the race, some may even do it routinely during a pitstop like
Champcars/Indycars and to a lesser extent F1.

See above.

They are open wheelers (but so is my neighbour's quad bike).

Which of the above are F1 "style" categories?

Generally speaking F1 style categories are slicks and wings with
more power than grip.

Huh! F1 cars do NOT have slicks!

Correct, these days they don't (although the FIA do refer to them as grooved
slicks) but to a casual observer it's easy to decribe something like an
F3000 car as being F1 like rather than NASCAR like.

--
James...
www.jameshart.co.uk

"BackToNormal" wrote

Huh! F1 cars do NOT have slicks!

ronh

It is being discussed for the future.
http://f1.racing-live.com/en/index.h...05013503.shtml

Pete

"John R Weiss" wrote:

"Mikko Pietilä" wrote...

In over 1700 A-4 hours, I never had an asymmetric slat extension that I could
not quickly and easily control. After about 1000 hours, few of them were even
unpredictable...

I wonder if you could try to describe, as well as you can recall, what
exactly happens during an asymmetrical slat extension?

That part is easy -- the airplane rolls toward the side with the unextended (or
less-extended) slat.

The difficulties arise when the slat extension is either at greater than 1 G,
very close to another airplane, and/or in the hands of an unexperienced pilot at
the top of a loop. Higher G causes a higher roll rate. If you're in close
formation and do not correct in time, you might roll into the other airplane.
If you put in the wrong control corrections at low speed (e.g., at the top of a
loop), you may depart, stall, and/or spin the airplane. Most of the training
Command mishaps related to asymmetrical slat extension, with which I am
familiar, were of the latter variety (departure or loss of orientation and
control in "unusual" attitudes).

Normal correction was to simply "pop" the stick slightly to one side, opposite
the roll, and the other slat would extend normally. However, if (due to a poor
preflight) the second slat was sticky enough to not deploy, and the AOA was
maintained high enough to keep the first one all the way out, an unexperienced
pilot could lose control. Otherwise, the airplane was controllable with
asymmetric slats.

. . .

If the wing area increases (as probably is the case with A-4, judging
from the photo I have) as the slat extends, the aircraft would tend to
roll extended slat up. Right?

Right.

Though the dynamics may be a bit more complicated than apparent from a simple
illustration, the net result of slat extension, in all the airplanes I've flown
that had them, is an increase in lift. Contributing to the increase a

Increased wing camber
Increased effective wing area
Energized airflow through the slot delays flow separation further back on
the wing


However, if the geometry is such that the leading edge moves down as
the slat extends, one could argue that the AOA of the profile
decreases causing roll towards the extended slat.

Though the apparent AOA may decrease, I suspect the other factors prevail.
Remember that with an aerodynamically-controlled slat, the wing is already at a
relatively high AOA when it deploys. I am not an aerodynamicist, but somebody
else may be able to give some insight into the relative contributions of the
different factors.


Or, if the slat extension causes a change of pressure distribution
around the aileron (the aileron snatch reported by the British BF-109
test pilots ?) moving the ailerons (probably not on the hydraulic
irreversible(?) control system of the A-4) until the pilot corrects
it, the roll could be either way.

I'm not familiar with the "aileron snatch" you describe, but I think I can
picture it in my mind. I would guess that has to do with the point at which
flow separation occurs on the wing. If flow is instantly, and asymmetrically,
restored over the aileron, the ailerons may be pulled in that direction, causing
the opposite roll. If this is the case, the AOA at which the slats start to
deploy, and the rate at which they deploy, would likely be adjusted in the
design phase.


Very interesting...
--

-Gord.

On 11 Jan 2004 18:20:04 GMT, (Smartace11) wrote:

Lots of autos have spoilers, as they push down on the rear for more rear
wheel loading. some formula one style racers have computer controlled
spoilers they call "spoiler flaps", so as to differentiate from a fixed
spoiler.

Formula One type open wheel cars cars don't have active aerodynamic surfaces
anywhere, flaps, spoilers, whatever. They are fixed. The fixed surfaces are
called wings and barge boards. They can be adjusted by the pit crew with tools
for track conditons. The only thing computer controlled by the computer aside
from the engine under present FIA rules is the traction system.

NASCAR uses spoilers that pop up when a car or truck is going
backward; these are designed to generate drag, spoil lift, and slow
the vehicle down while encouraging it to stay on the ground.

You can see them when they open; they're just in front of the back
window. They're pretty conspicuous.

Mary

--
Mary Shafer Retired aerospace research engineer

On Sun, 11 Jan 2004 13:13:00 GMT, "Dudley Henriques"
wrote:

The Blues bolted 'um shut. Can you imagine what would happen in a tight
diamond with an A4 if a wing position got an asymmetrical slat extension
with roll induced....say in a barrel roll? Not a pretty thought!! :-))

Or you could ask Steve what happens when one F-18 slat popped up over
the stops and got stuck, perpendicular to the airflow. Not a pretty
sight at all.

Of course, the O'Hare DC-10 had a slat asymmetry, although that was an
asymmetric retraction of an extended slat. Subsequent simulator
studies showed that, even knowing the problem was asymmetric slats,
the airplane was too low to recover.

Mary

--
Mary Shafer Retired aerospace research engineer

(B2431) wrote in message ...
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


Dan, Tarver lost me with the fixed spoiler,what purpose would it
serve on an aircraft.It would be pretty silly to have a spoiler fixed
stowed or deployed. Then again you have to consider the source of this
information.I am still looking for section 40 on Boeing aircraft.

Frank M.Hitlaw

On Mon, 12 Jan 2004 23:03:31 -0800, Mary Shafer
wrote:

Of course, the O'Hare DC-10 had a slat asymmetry, although that was an
asymmetric retraction of an extended slat. Subsequent simulator
studies showed that, even knowing the problem was asymmetric slats,
the airplane was too low to recover.

Mary

If we're talking about the same DC-10 that was lost at O'Hare about 20
years ago, the slat assymetry was caused by the engine and pylon
departing the wing, up and over and in the process taking a chunk of
leading edge with it.

The accident investigation and subsequent simulator trials
demonstrated fairly conclusively that the aircraft was recoverable,
however training to immediately pull up and reduce speed to Vmc was
incorrect. What was needed was the more high performance airplane
practice of "unload for control" in which you (counter-intuitively)
ease off the back pressure possibly all the way to zero G and let
airspeed build to a point where more G is available for the recovery.


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