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raaaid
04-25-2007, 05:29 AM
yesterday i watched a program about pilots ejecting

i saw a guy trying to bail out in a wind tunnel and he couldnt

but the speed of air over your head is much faster than in your feet

shouldnt it happen the same than with a wing and occur lift?

on the other hand this could be avoided using negative g in which the game aint posible

this are the kind of things than can only be seen experimentally being science so far from reality

you cant even bail out at high speed with the plane upside down what means that in this case the bigger the speed of air the bigger the pressure

raaaid
04-25-2007, 05:29 AM
yesterday i watched a program about pilots ejecting

i saw a guy trying to bail out in a wind tunnel and he couldnt

but the speed of air over your head is much faster than in your feet

shouldnt it happen the same than with a wing and occur lift?

on the other hand this could be avoided using negative g in which the game aint posible

this are the kind of things than can only be seen experimentally being science so far from reality

you cant even bail out at high speed with the plane upside down what means that in this case the bigger the speed of air the bigger the pressure

x6BL_Brando
04-25-2007, 05:54 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
yesterday i watched a program about pilots ejecting

i saw a guy trying to bail out in a wind tunnel and he couldnt

<span class="ev_code_YELLOW">which is why the ejector seat was invented</span>

but the speed of air over your head is much faster than in your feet

shouldnt it happen the same than with a wing and occur lift?

<span class="ev_code_YELLOW">People are not wing-shaped - and cannot fly without using some kind of winged device</span>

on the other hand this could be avoided using negative g in which the game aint posible

<span class="ev_code_YELLOW">We can't expect everything we want</span>

this are the kind of things than can only be seen experimentally being science so far from reality

<span class="ev_code_YELLOW">Bearing in mind that science is the study of reality it's hard to see your point. While science may be far away from understanding the totality, if science deals with facts and truths (rather than myths and fantasies), it's hard to see why there should be some huge gap.</span>

B
</div></BLOCKQUOTE>

raaaid
04-25-2007, 06:31 AM
the venturi effect says that a stream of fluid at high velocity(air above the pilot) will pull particles underneath(pilot)

it doesnt say the particles must be winged shape

if i fill the cannopy with water and make it through a wind tunnel pressure in the top will be smaller and water should come out but as with the pilot it doesnt happen

i dont understand it so i ask


maybe when you measure pressure for bernuolli to work the barometer can only be perpendicular to the stream

raaaid
04-25-2007, 06:57 AM
i just found out somethin aint in the textbooks

here you have an application of bernuolli:

http://en.wikipedia.org/wiki/Image:Venturifixed2.PNG

notice the vertical tubes in which the column of liquid indicates the pressure, where its shorter theres less pressure

now imagine you lean the right tube 45º to the right, THE PRESSURE WILL RAISE

the pressure will be bigger where the fluid goes faster because the tube is leaned

tell me this is no interesting

thats what happens with the shooter he offers more vertical surface(to the stream) than horizontal

Capt.LoneRanger
04-25-2007, 07:16 AM
You're forgetting a little detail (again) raaaid.

The speed of air at the pilots feet is that low, because it is stuck in the cockpit. You're breaking your head over a theoretically pilot hanging in an airstream. But before the pilot bails out, he's in a cockpit and the air flows over the canopy with high pressure and that very same pressure finds a hole =&gt; the open cockpit, and presses into that, literally pressing the pilot in his seat.

You can try that yourself driving in a car. Open the window for the front passengers and let somebody sit on the back. The wind presses in and makes a mess out of your passengers hair-style. Now imagine you drive 500kph.

Treetop64
04-25-2007, 07:19 AM
You're missin' it, raaaid...

Again (and typically)you are over-generalizing the setup here, and making grossly simplistic assumptions.

When describing the venturi effect the shape of the body that the air is moving over (or under) has everything to do with weather or not the venturi effect (or the Bernuolli effect, for that matter...)is taking place.

The particles themselves are not the ones being described as "wing shaped", raaaid, but the body they are moving across.

For example, say you have an inverted wing held just above the ground, with the lowest part of the wing just an inch from the ground. There is a steady airflow moving across the wing, from the leading edge to the trailing edge. At the point where the lowest part of the wing is closest to the ground the air will be traveling the fastest, while the further back along the wing the air flows, the more it slows down, as there is more and more space between the wing's surface and ground the closer you get to the trailiing edge. The area where the wing surface is closest to the ground is a low pressure zone, because the air molecules (or "particles", if you will) are moving fastest through this area. Here the wing will be "sucked" to the ground because of this low pressure zone. The "venturi" is actually the flare of the wing after the low pressure zone (that being the area of the wing that is further and further from the ground the closer to the trailing edge you get. Remember, we're talking about an inverted wing here). The effect is greater the faster the airflow. This is basically how ground-effects racing cars create downforce under the cars, for example.

The example you're using (pilot in the cockpit) only creates a lot of turbulence and eddies because there is no aerodynamic harmony between the airflow, and an open cockpit, and the bulk of the pilot, and the utilitarian space that is the cockpit.

I'm sure I got the basics right, but perhaps someone with more expertise can make a better explination.

I remember you asking about this very same issue months ago. You asked if pilots would literally be sucked out of their open cockpits if they weren't strapped in and the universal answer you got was "NO".

It's great you're so inquisitive about these things, raaaid, but your mind always seems to go down when it should be going up... http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif

Capt.LoneRanger
04-25-2007, 07:22 AM
Don't we just love raaaid? http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Treetop64
04-25-2007, 07:33 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
...now imagine you lean the right tube 45º to the right, THE PRESSURE WILL RAISE

the pressure will be bigger where the fluid goes faster because the tube is leaned...
</div></BLOCKQUOTE>

...how so? http://forums.ubi.com/images/smilies/blink.gif

Dood, you're making absolutely no sense at all. Pressure inside the narrow part of the tunnel isn't gonna change just because the tube is leaning at an angle.

Treetop64
04-25-2007, 07:34 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Capt.LoneRanger:
Don't we just love raaaid? http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif </div></BLOCKQUOTE>

Sometimes... http://forums.ubi.com/images/smilies/shady.gif

Capt.LoneRanger
04-25-2007, 07:45 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Treetop64:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Capt.LoneRanger:
Don't we just love raaaid? http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif </div></BLOCKQUOTE>

Sometimes... http://forums.ubi.com/images/smilies/shady.gif </div></BLOCKQUOTE>

http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

I just can't understand why he was banned from this physics/mathematics-forum. After all, they finally turn out to be boring and without a sense of humor. http://forums.ubi.com/images/smilies/35.gif

LStarosta
04-25-2007, 07:55 AM
I had a little chat with a certain Vietnam War Thud driver by the name of Leo Thorsness and he told me that when he was flying Wild Weasel, he got intercepted by a MiG at low level, he got hit pretty bad and had a choice to make. He was doing 600+ knots which is well above safe eject speed, but if he waited any longer, his airframe would disintegrate from under him. So he ejected and the force caused by the airflow tore his knees apart and messed up his groin.

Agamemnon22
04-25-2007, 08:06 AM
I'm going to be the devil's advocate here and bring up this incident, which I'm sure you've heard about:

06/10/1990 c 08:20
LOCATION: Oxfordshire, England
CARRIER: British Airways FLIGHT: 5309
AIRCRAFT: BAC One-Eleven
REGISTRY: S/N:
ABOARD: 85 FATAL: 0 GROUND:
DETAILS: On a flight from Birmingham, England to Malaga, Spain,
at FL 230, a large section of windshield fell away from the aircraft.
The decompression pulled the captain out from under his seatbelt.
Despite trying to hold onto the yoke, the captain was sucked out into
the opening. A steward in the cockpit was able to grab hold of his
legs. Another steward was able to strap himself into the vacant seat
and aid in holding onto the captain's legs. The copilot wearing full
restraints made an emergency landing at Southampton. The captain
remained half way out of the aircraft for 15 minutes and suffered
only frostbite and some fractures. Improper bolts used to replace the
windshield two days earlier.


So a pilot can be sucked out of a cockpit under the right conditions. However, the problem with bailing out at high speed is not the suction, but the pressure of the wind upon the pilot once he pokes his head out of the cockpit and becomes an obstacle in the airflow. Try sticking your hand out of your car window at 100kph.. feel a bit of pressure? now get a faster car and try it at 500kph.. it might break your arm http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

So the reason you can't willfully bail out at high speed is that no one is strong enough to fight the onrushing air, nothing to do with Bernoulli...

raaaid
04-25-2007, 08:53 AM
"Dood, you're making absolutely no sense at all. Pressure inside the narrow part of the tunnel isn't gonna change just because the tube is leaning at an angle"

bernuolli put a vertical tube on an horizontal tube and found out that the level in the vertical tube reduced as the speed in the horizontal tube increased

therefore he cocluded the highest the speed the lower the pressure

i disagree, take you lean the vertical tube 89º

now the faster the fluid in the horizontal tube the higher the level will raise in the 89º tube

this is obvious if you think the 89º tube has almost the same direction thanthe horizontal one, so the fluid tends to get into the89º tube easily, is like a bifurcation

on the other hand if you lean 89º the vertical tube to the other side hardly any fluid will get in

so the level of the tube leaned to the right will be higher than the one lean to the left(if the fluid goes to the right)

LEBillfish
04-25-2007, 09:03 AM
I'd tell him but he has me on ignore http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

Capt.LoneRanger
04-25-2007, 09:05 AM
Forgive me, but are you really sure you understood Bernoullis experiment there? If you set up a T-junction as in the experiment, the pressure is lowered, because the water from above lowers the motion of the stream in the other tube. You cannot increase speed or pressure by changing the angle, though. The turbulence will just lower and near the normal level.

So, changing the angle of the pilot in an airstream won't make him skyrocket, sorry.

@ Agamemnon22
We're talking about overpressure due to high speeds, here, not high altitude underpressure. We will have that in our lesson next week. http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

rnzoli
04-25-2007, 09:10 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Agamemnon22:
So a pilot can be sucked out of a cockpit under the right conditions. </div></BLOCKQUOTE>
Pressurized cockpits are a good start http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

WB_Outlaw
04-25-2007, 09:16 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
"Dood, you're making absolutely no sense at all. Pressure inside the narrow part of the tunnel isn't gonna change just because the tube is leaning at an angle"

bernuolli put a vertical tube on an horizontal tube and found out that the level in the vertical tube reduced as the speed in the horizontal tube increased

therefore he cocluded the highest the speed the lower the pressure

i disagree, take you lean the vertical tube 89º

now the faster the fluid in the horizontal tube the higher the level will raise in the 89º tube

this is obvious if you think the 89º tube has almost the same direction thanthe horizontal one, so the fluid tends to get into the89º tube easily, is like a bifurcation

on the other hand if you lean 89º the vertical tube to the other side hardly any fluid will get in

so the level of the tube leaned to the right will be higher than the one lean to the left(if the fluid goes to the right) </div></BLOCKQUOTE>

raaaid, just post your calcs that show WHY inclining the tube will result in a pressure change as you suggest.

--Outlaw.

JR_Greenhorn
04-25-2007, 11:51 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
"Dood, you're making absolutely no sense at all. Pressure inside the narrow part of the tunnel isn't gonna change just because the tube is leaning at an angle"

bernuolli put a vertical tube on an horizontal tube and found out that the level in the vertical tube reduced as the speed in the horizontal tube increased

therefore he cocluded the highest the speed the lower the pressure

i disagree, take you lean the vertical tube 89º

now the faster the fluid in the horizontal tube the higher the level will raise in the 89º tube

this is obvious if you think the 89º tube has almost the same direction thanthe horizontal one, so the fluid tends to get into the89º tube easily, is like a bifurcation

on the other hand if you lean 89º the vertical tube to the other side hardly any fluid will get in

so the level of the tube leaned to the right will be higher than the one lean to the left(if the fluid goes to the right) </div></BLOCKQUOTE>raaaid, you cannot lean the vertical tube because you will no longer be measuring only static pressure. Leaning the vertical tube towards the horizontal introduces a dynamic pressure component and reduces the measured static pressure by that component.

The reduction in static pressure from point 1 to point 2 (in the venturi you posted), should be equal to the increase in dynamic pressure between those two points. The total pressure, the sum of the static and dynamic pressures, should be the same at both points. I do not have my textbooks handy, so I can't verify this for you right now, but rest assured this was covered in detail in my textbooks.


Additionally, I think a venturi makes a poor model of an aircraft with an open cockpit.

Stackhouse25th
04-25-2007, 11:54 AM
the principle of the principality of the principle argument states that the recent advances in molecular misunderstanding is quite well placed in a wind tunnel and given devices such as wind and pressure it cannot and should not be possible for a daring intrepid young aviator to bail out of his plane at high velocities due to forces that are well known, common, and albeit puzzling, but not impossible to understand, there be a pizza man taking his pizza by aeroplane and this is just another one of those things that happens and then he lands and gets out, the end.

Zeus-cat
04-25-2007, 01:01 PM
LEBillfish said <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I'd tell him but he has me on ignore </div></BLOCKQUOTE>

How do you get on raaaid's ignore list? That would be kool; something to brag about I think.

raaaid
04-25-2007, 02:00 PM
thank you so much guys thanks to the venturi clue after all this work i finally reach a free energy example which i just experimented succesfully

take a 10 m long cilinder 2 m wide, cover the top and put it on water in such way that the level inside the cilinder is 10 m above sea level

take a 1 square m float,and put it inside the cilinder from sea level it will float 10 m up

now cover the bottom of the cilinder and then uncover the top, take the float and let it drop

now cover the top of the cilinder and uncover the bottom and repeat the proces

free energy of the best kind, this proves conservation of energy is wrong and the petrol companies even control the textbooks

WB_Outlaw
04-25-2007, 02:40 PM
Post a picture for pete's sake!!!

I'm usually pretty good at translating raaaid's posts but this one has got me stumped. The most important step he's missing is the, "...and then a miracle occurs...", step.

Of course, if you ASSUME that the, "...put it on water in such a way...", step consumes no energy, then it may actually work.

--Outlaw.

WB_Outlaw
04-25-2007, 02:51 PM
Nevermind, I see what he's saying now and, while energy is obviously conserved, it is an interesting idea. I'm not sure how much useful work could be extracted though.

--Outlaw.

LStarosta
04-25-2007, 02:54 PM
Now I know raaaid is a troll.

Who are you going to get to turn and cover/uncover the cylinder? Illegal Mexicans? Maybe... Slaves? Most likely. If this is your attempt to relegalize slavery in the United States, you will fail, you disgusting sick racist f*ck!

Maj.Kaos
04-25-2007, 04:49 PM
I want to see some charts and tracks.



On second thought, I don't.


Never mind. Next topic.

WarWolfe_1
04-25-2007, 06:06 PM
Ahhhhhhhh......another raaid thread, and I was getting sleppy http://forums.ubi.com/images/smilies/35.gif

na85
04-25-2007, 07:51 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">this proves conservation of energy is wrong and the petrol companies even control the textbooks </div></BLOCKQUOTE>

This is possibly the least intelligent comment I've ever read, anywhere, in all the twenty-one years of my life. Any university textbook will tell you that no known process has violated the conservation of energy principle.

Also, FFS, it's spelled "Bernoulli" not "Bernuolli"

gdfo
04-25-2007, 08:14 PM
I wish I could remember the title of the book.
I had copy of it long ago. The true story of a pilot who was flyin cross country in the USA.

He was in a Chance-Vought Crusader at high altitude and over mach one. The craft had a problem and the pilot ejected at high alt and over mach one. He also ejected over a thunderstorm. He did survive. He was also severely injured from the decompression and also the effect of the air blast. His 'chute was almost destroyed from his decent through the storm. I remember that he had a couple of broken bones and some hearing problems and many capillaries in his eyes had burst.

It is possible to eject at over mach 1 and survive and it is possible to do so at alt over 10,000 feet. It was not, however an experience that leaves the pilots uneffected for the rest of his life.

Wish I could remember the name of the book.

Perhaps it is 'The Man Who Road the Thunder'

berg417448
04-25-2007, 08:17 PM
I remember reading that book. The Man Who Rode the Thunder:

http://www.amazon.com/Man-Who-Rode-Thunder/dp/0135482712

Zeus-cat
04-25-2007, 09:38 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">This is possibly the least intelligent comment I've ever read, anywhere, in all the twenty-one years of my life. Any university textbook will tell you that no known process has violated the conservation of energy principle. </div></BLOCKQUOTE>

You must be new to the forums. Actually, this is one of raaaid's more reasonable ideas. raaaid rejects traditional scientific explanations for most things and is obsessed with finding a source of free energy. There is no point in trying to teach him anything as he typically ignores any explanation that conflicts with his view of the world.

I have found that one of the best ways to enjoy a raaaid thread is to ignore his original post and start with the first response and go from there. Oddly enough, I think they make more sense that way.

Treetop64
04-25-2007, 09:58 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by LStarosta:
Now I know raaaid is a troll.

Who are you going to get to turn and cover/uncover the cylinder? Illegal Mexicans? Maybe... Slaves? Most likely. If this is your attempt to relegalize slavery in the United States, you will fail, you disgusting sick racist f*ck! </div></BLOCKQUOTE>

OMG!!! http://forums.ubi.com/images/smilies/88.gif http://forums.ubi.com/images/smilies/88.gif http://forums.ubi.com/images/smilies/88.gif http://forums.ubi.com/images/smilies/88.gif http://forums.ubi.com/images/smilies/88.gif

M_Gunz
04-25-2007, 10:00 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
this are the kind of things than can only be seen experimentally being science so far from reality </div></BLOCKQUOTE>

You sit at a computer and write that?

It is not the science that is far from reality. If that were true then most technology you
live by today would not be working. But then you could maybe fit in with the Almish.

What is far from reality is how you attempt to apply limited science to reality.

Open pit and highspeed air streaming over there will be a flow into the pit and circling inside
while some is sucked out. Much turbulence that presses into the pit.

The difference between your model and the reality is not the failing of science. But I have a
feeling that it was the show that presented the model and the show that tries to say that the
science has failed, which is a common thing for those intimidated by science or math.

Article in Science News (http://www.sciencenews.org/articles/20040911/mathtrek.asp)

"The distinction between mathematics and the application of mathematics often isn't made as clearly as it ought to be. In the mathematics classroom, it's important to distinguish between getting the mathematics right and getting the problem right."

Something that most people get wrong and don't believe they have. The example they show is
about the "science proved that bumble bees can't fly" fallacy. The more scared someone is of
science, the tighter they hold on to anything that says science is wrong. Perhaps they should
go live in rough conditions without electricity or anything that uses it, without anything that
uses vacuum or air pressure or steam or even gunpowder since all of that took science to make.
For those people to walk around in this world disclaiming science is as stupid as actually
claiming that bees can't fly.

M_Gunz
04-25-2007, 10:19 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raaaid:
thank you so much guys thanks to the venturi clue after all this work i finally reach a free energy example which i just experimented succesfully

take a 10 m long cilinder 2 m wide, cover the top and put it on water in such way that the level inside the cilinder is 10 m above sea level

take a 1 square m float,and put it inside the cilinder from sea level it will float 10 m up

now cover the bottom of the cilinder and then uncover the top, take the float and let it drop

now cover the top of the cilinder and uncover the bottom and repeat the proces

free energy of the best kind, this proves conservation of energy is wrong and the petrol companies even control the textbooks </div></BLOCKQUOTE>

Experimented successfully? You DID this? Not just THOUGHT ABOUT IT?

And whatever you did, it is not just as written above because if your 1 sq m float (shouldn't
that be 1 CUBIC meter? otherwise your float is a flat sheet) would go nowhere unless you
moved the cylinder up and down which would require you to input energy.

In the start you have the cylinder with water inside 10m above sea level. To do that you have
to LIFT the water above sea level and that takes energy.
Then you have the float rise and then you have the water drain so the float can fall.
And if you want the float to rise again, you have to lift the water yet again, which takes energy.

So with you putting energy to lift a column of water 10m in order to get less energy from
the motion of the float, where is the "free energy"? I guess the water gets energy free
from you!

If you really did some kind of modeling then sorry but you missed steps and if you really
just thought about it and somehow can't tell thought from reality then get to a doctor,
they have pills and treatments for schizophrenia.

OTOH, it could be the mind spy rays have done this to you so be sure and wear a double-thick
tinfoil hat when you go to see that doctor! For sure the doctor will understand!

M_Gunz
04-25-2007, 10:22 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by LStarosta:
Now I know raaaid is a troll.

Who are you going to get to turn and cover/uncover the cylinder? Illegal Mexicans? Maybe... Slaves? Most likely. If this is your attempt to relegalize slavery in the United States, you will fail, you disgusting sick racist f*ck! </div></BLOCKQUOTE>

For one, he is in Spain... and Bush would never go for it.

Yeah, I know, you were trying to be funny like usual. http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif