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Post by clockwork on Feb 2, 2006 6:45:17 GMT -5
I am told there are about 5 pages of this boring rubbish on "The Beige Side" - as Chris fully knows. HAHAHA Cothi is Secret "Beige Side" Poster! ;D A friend told me? The Cheque is in the post? Of course I love you?
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Post by MichaelL on Feb 2, 2006 6:57:59 GMT -5
I am told there are about 5 pages of this boring rubbish on "The Beige Side" - as Chris fully knows. I think there are about 5 or 6 variants of this that been going for a while...
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Post by Chris on Feb 2, 2006 6:58:07 GMT -5
Cothi, "about 5" is in fact 12.
Boring? don't read it.
Interesting? Then post.
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Post by clockwork on Feb 2, 2006 6:58:30 GMT -5
quote]
Sounds really similar to the treadmill, but it isn't. On the treadmill you're running forward - think of that as the thrust of the plane engine. If you ran along a road your airspeed would increase
[/quote]
Running means your forward motion is derived from pushing against the ground.
The plane gets forward motion from pushing against the air. The wheels only keep it off the gound and let the pilot steer and land safely, they have NOTHING to do with the drive of the plane, and whatever they touch has NOTHING to do with the forward motion of the plane.
TP imagine this plane taking off on a frozen lake.
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Post by T.P. on Feb 2, 2006 7:08:27 GMT -5
Cothi, "about 5" is in fact 12. Boring? don't read it. Interesting? Then post. Seriously Chris, you have to get over your forum sensitivity. Cothi was being funny, don't take it to heart, your constant defending your forum is becoming very boring and is totally unnescessary. Clockwork, wouldn't work on a frozen lake either, unless they had spiked tyres and actually moved forward. Wherever you are right now, stand up and run on the spot, hear any air past your ears? I have long hair so I have a built in wind sock. My hair only flows backwards when I run along a road, in the gym on the treadmill it just bounces up and down. T.P.
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Post by Cothi on Feb 2, 2006 7:18:49 GMT -5
Cothi, "about 5" is in fact 12. Boring? don't read it. Interesting? Then post. Heh - Heh
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Post by MichaelL on Feb 2, 2006 7:47:48 GMT -5
and whatever they touch has NOTHING to do with the forward motion of the plane. That would be correct if there was a frictionless surface.
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Post by nicepix on Feb 2, 2006 7:55:19 GMT -5
Cothi, "about 5" is in fact 12. Boring? don't read it. Interesting? Then post. Heh - Heh Stockie Basher!
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Post by Gander on Feb 2, 2006 8:18:05 GMT -5
In the interests of science, I have carried out an experiment to answer this question.
In the gymnasium at my work, I took the part of a plane, and ran on a treadmill machine until I reached what I estimated would be my optimum lift off speed if I was running on solid ground.
It has been several years since I've done any serious running, but I feel that my estimation of lift off speed was pretty close to what it used to be. The only complication is the fact that I may have increased in bulk, weight and surface area since the last time I reached lift off point.
After establishing lift off point, while speeding up the machine to maintain no forward motion, I can confirm that at no point did I feel "airflow" over my face, nor did I detect any capability to lift off. I assumed that this was due to the afore mentioned increased mass, so I compensated by increasing machine and leg speed. Still no compulsion was felt to take off.
Following 2 minutes at above my old optimum lift off speed, I experienced a sudden fuel and air starvation failure to my primary drive systems. This led to a catastrophic electrical failure to my main inflight logic system, meaning that as my legs stopped moving, my brain failed to tell my hand to switch the machine off.
Rapidly following this series of events I can confirm that I did indeed achieve flight. About ten feet, backwards off the end of the treadmill over two rowing machines and a fellow worker using an Ab-roller.
Therefore, the answer to the question is yes, the plane will fly once it runs out of fuel, albeit backwards and for a short distance off the back end of the conveyor belt.
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Post by FlyBri on Feb 2, 2006 8:37:11 GMT -5
Very good ;D
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Post by Silver Stoat on Feb 2, 2006 8:54:49 GMT -5
Yes Gander, very good and technically correct. As stated above, the only way it could take off without airflow around the wings would be if it was a VTOL aeroplane (or a helicopter) where the thrust of the engines acting vertically would cause it to rise.
To re-state the basics, the wing (the 'plane' in "aeroplane") must have airflow over it in order to create reduced air pressure on it's upper surface in order to achieve lift. In the conditions stated, the aeroplane would be static, there would be insufficient airflow over the wings to generate lift and aeroplane would not fly.
I any normal circumstances it would though, providing it was in a serviceable condition and had a pilot to fly it !!
Dave.
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Post by Dom on Feb 2, 2006 9:00:33 GMT -5
OK So the airplane has wheels that are not powered. They are in effect free coasting. The engines are what power the plane. Would this not be like a hovercraft on a treadmill. The hovercraft would stay stationary, regardless of what the treadmill does. As soon as the fans (or aircraft engines kick in) the plane/hovercraft will move forward. Again regardless of what the treadmill was doing. Therefore forward motion would be gained, lift, take off etc. On the "beige place" there were 12 pages of discussions with pilots and everything. We could not agree so had to agree to disagree.
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Post by guinea on Feb 2, 2006 9:06:46 GMT -5
Yes is will take off.
People, planes do not take off using power from wheels, so the plane will accelerate and move forward regardless of what is going on underneath it.
When it reaches enough speed it will take off.
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Post by tigermoth on Feb 2, 2006 9:30:11 GMT -5
Now then - think about when you run on a treadmill in a gym (god forbid) - as you increase your running speed, you can increase the speed of the treadmill. Do you feel the force of air/wind in your face..............? No you don't feel the wind increase. There are 2 speeds in flying, ground speed and airspeed. Your ground speed can be zero (you're basically going nowhere) but you won't drop out of the sky if you have sufficient airspeed. How does this work? Well if you're moving forward via jet propulsion and the head wind is the same as your forward thrust then you're going nowhere but there is lots of air flowing over the wings, creating lift. Sounds really similar to the treadmill, but it isn't. On the treadmill you're running forward - think of that as the thrust of the plane engine. If you ran along a road your airspeed would increase (you hear the air flow past your ears). When you're standing still and running (EDIT, that was very Irish as my Mother would say, I mean running on the spot), no airflow past your ears. No airflow, no lift. This plane could theoretically take off if the flaps were in the right position and wind was blown at a strong enough strength to create enough airflow to create lift. This is how a kite works when you first let go of it. Planes need a lot of airspeed to take off, hence the huge acceleration and they take off into the wind. When thinking about planes flying, think about kites or in my case hang gliders, they display exactly the smae principles as planes but in much simpler ways. If you ran on the spot with a kite in your hand and let go, what would it do? I don't think I've explained this very well. I hope this is a question with some jokey answer and we're all wrong! T.P. Wonderful stuff T.P. - couldnt have explained it better myself - in fact couldnt have explained it all You can come and teach in my school anyday
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Post by T.P. on Feb 2, 2006 9:30:37 GMT -5
Gander - great post, but we need you to do the experiment ever so slightly differently! :-) Do you have any roller skates? :-)
Here are my last thoughts:
You are standing still on a conveyor belt with roller skates on, the wheels are not turning. Someone pushes you from behind.
If the belt didn't move, you'd move forward in relation to the earth.
If the belt moves, the wheels would turn but you'd go nowhere.
I understand that the belt moves in this question and no matter how hard you are pushed on the wheels, the belt prevents you from gaining any ground.
If you gain no ground, no air speed, no lift.
I understand that there is no definative answer to this which is very annoying. Maybe we'll see it mocked up on TV some time.
T.P.
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