The Virtual Pub
Come Inside... => The Snug => Topic started by: Barman on April 28, 2007, 04:19:47 PM
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I saw this on another board and couldn?t believe the amount of discussion that ensued ? to me the answer is obvious (but I won?t tell you what I think yet).
What thinks you lot?
A plane is standing on runway that can move (some sort of band conveyor). The plane moves in one direction, while the conveyor moves in the opposite direction. This conveyor has a control system that tracks the plane speed and tunes the speed of the conveyor to be exactly the same (but in opposite direction).
The question: Will the plane takeoff?
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Yes ............... Er ....................No ............................ Er ...........................Maybe confused:
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Yes ............... Er ....................No ............................ Er ...........................Maybe confused:
Banghead
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Look ~ I only used to mend them ..... flying the damn things wuz Hofficer's work.
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Here ? I?ve added a poll to make it easy for the lower ranks. wink:
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I'm going to say no!
Just so that you can all laugh at me when I get it so terribly wrong. redface:
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Vote then! noooo:
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I did I did I did
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Happy now!
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Happy now!
Oh yes... cloud9:
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A plane is standing on runway that can move (some sort of band conveyor). The plane moves in one direction, while the conveyor moves in the opposite direction. This conveyor has a control system that tracks the plane speed and tunes the speed of the conveyor to be exactly the same (but in opposite direction).
The question: Will the plane takeoff?
Absolutely not. If the conveyer and aircraft speed is equal then it will be stationary.
If it is stationary then it cannot generate the lift needed to rise.
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A plane is standing on runway that can move (some sort of band conveyor). The plane moves in one direction, while the conveyor moves in the opposite direction. This conveyor has a control system that tracks the plane speed and tunes the speed of the conveyor to be exactly the same (but in opposite direction).
The question: Will the plane takeoff?
Absolutely not. If the conveyer and aircraft speed is equal then it will be stationary.
If it is stationary then it cannot generate the lift needed to rise.
Now let's not be silly here ~ No airport has yet managed to get moving "walkways" and their handrails to syncronise ie move at the same speed ~ how the hell does anyone think they are going to get an aircraft and conveyor to move in opposite directions at the same speed?
It's like .... er .... patting your head with one hand and rubbing your belly in a circular motion with the other hand at the same time ~ just not do-able.
I am ex RAF you know ..... we know what is not possible (most things actually)
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I have a witness to verify clockwise and anti-clockwise tummy rotations and head pats with either hands at will.
Shoulda joined the army...... point:
Postscript:
How far can you lower a rope down a hole?
No tricks.
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I have a witness to verify clockwise and anti-clockwise tummy rotations and head pats with either hands at will.
Shoulda joined the army...... point:
Postscript:
How far can you lower a rope down a hole?
No tricks.
I am impressed ~ it is all I can do to turn the pages of the magazine with one hand these days!
Edit: This board is getting harder to use too. What's with this quick reply stuff ~ I can't find the emots on it!
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I am impressed ~ I can hardly manage to turn the pages of the magazine one handed these days.
Aha.. now that's a different matter altogether! The circle and pat thing has been one of those 'Party tricks' I could always do like the 'Vulcan' salute.
It was supposed to make me able to play the piano - but I could never get my two hands doing different things in that way - a complete failure! I can however, play each half separately one at a time. Very useful.
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Now then ...... Rope, hole whistle: whistle: whistle:
To the bottom so long as you let go of both ends lol:
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Um? you can reply quickly? ;-)
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Edit: This board is getting harder to use too. What's with this quick reply stuff ~ I can't find the emots on it!
Use the preview button and it switches into normal mode where you can insert the Emoticons anywhere you want afterwards....
dogrun:
Like this!
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Now then ...... Rope, hole whistle: whistle: whistle:
To the bottom so long as you let go of both ends lol:
Nope! Use logic...
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Edit: This board is getting harder to use too. What's with this quick reply stuff ~ I can't find the emots on it!
Use the preview button and it switches into normal mode where you can insert the Emoticons anywhere you want afterwards....
dogrun:
Like this!
NOBODY LOVES A SMARTARSE! evil:
Hey! It works.
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Logic... whistle:
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What about some Karma then skinflint... cool:
I've only got 1 cry:
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Luckily you are still positive... point:
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Don't do logic but I've given you some applause ~ not a lot mind, there's still that matter of the fur-ball I found whilst cleaning up here this morning.
Blimey that was quick ~ There it was ..... GONE!
I blame the boss.
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Sloopy! I was giving you +'s... noooo:
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Oh come ON! It's not that tough... rolleyes:
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I was never any good at these things. confused1:
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Sloopy! I was giving you +'s... noooo:
I have smote you for that blatant misspelling of my name ~ apparently I cannot restore the one clap (if you'll forgive the expression) I awarded Bouncer for an hour! evil:
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I just reported you for bad behaviour - to see what would happen....
Seems I sent a e-mail to myself telling me that you've been naughty.
Oh, and did I want to strip you of your post count or karma? hee hee.
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Postscript:
How far can you lower a rope down a hole?
No tricks.
I know....Please Sir, I know
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Sloopy! I was giving you +'s... noooo:
I have smote you for that blatant misspelling of my name ~ apparently I cannot restore the one clap (if you'll forgive the expression) I awarded Bouncer for an hour! evil:
Dear oh dear… you don’t learn do you? point:
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If you jump up and down for me then PG - Oh go on then... These dullards don't have the feline gifts.
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If it wasn't your ball I'd take it home and not come out again for two days. cussing:
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If it wasn't your ball I'd take it home and not come out again for two days. cussing:
Only two days? bs:
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If you jump up and down for me then PG - Oh go on then... These dullards don't have the feline gifts.
Sorry they jiggle on my page, but not on here. redface:
As far as I can work out using basic maths, the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break. lol:
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If you jump up and down for me then PG - Oh go on then... These dullards don't have the feline gifts.
Sorry they jiggle on my page, but not on here. redface:
As far as I can work out using basic maths, the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break. lol:
Um… and that has WHAT to do with the aeroplane on the treadmill thingy? noooo:
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I was answering the queston of the roap down the hole.
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Sorry they jiggle on my page, but not on here. redface:
As far as I can work out using basic maths, the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break. lol:
Smartarse....... thumbsup:
So... What about the Aeroplane then?
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I was answering the queston of the roap down the hole.
Roap? point:
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I was answering the queston of the roap down the hole.
Roap? point:
Tut and you should know better. I am slidexic KO...I normally check my posts but this one slipped through my fingers, a bit like that rope then....I was taken up on stage at assembly in school once and ridiculed by a load of Nun's because I spelled Blood -Blud in my Biology exam. Bloody penguins.
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I was answering the queston of the roap down the hole.
Roap? point:
Tut and you should know better. I am slidexic KO...I normally check my posts but this one slipped through my fingers, a bit like that rope then....I was taken up on stage at assembly in school once and ridiculed by a load of Nun's because I spelled Blood -Blud in my Biology exam. Bloody penguins.
I was answering the queston of the roap down the hole.
Roap? point:
Tut and you should know better. I am slidexic KO...I normally check my posts but this one slipped through my fingers, a bit like that rope then....I was taken up on stage at assembly in school once and ridiculed by a load of Nun's because I spelled Blood -Blud in my Biology exam. Bloody penguins.
Poor you… console yourself with having fantastic braests… wink:
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We are like kids with a new toy here. redface:
I just got reported back by Sloopy eeek:
You can run - but you can't hide
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This is a great new toy ? hopefully it will catch on! thumbsup:
But... back to the aeroplane... rolleyes:
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How come the one 'yes' vote has disappeared from the poll?
There'sa fings a'goin on around 'ere!
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How come the one 'yes' vote has disappeared from the poll?
There'sa fings a'goin on around 'ere!
I didn’t see a ‘yes’ vote but the forum, software allows users to change their vote… It’s an option but I set it to allow users top change vote’…
We obviously convinced somebody with our comprehensive technical discussion…
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Sorry, you can't repeat a karma action without waiting 1 hours.
It is hour, not hours for a single 1 you stupid machine. noooo:
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I smite you for conversing with a computer? noooo:
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Sorry, you can't repeat a karma action without waiting 1 hours.
It is hour, not hours for a single 1 you stupid machine. noooo:
Awww! Wuz you gonna be nice to someone then?
Somehow... your avatar change says 'No' confused:
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Sorry, you can't repeat a karma action without waiting 1 hours.
It is hour, not hours for a single 1 you stupid machine. noooo:
I’ll smite you again (in an hour) for changing your avatar… Angry9:
If you e-mail me the original picture I’ll applaud you later…
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Awww! Wuz you gonna be nice to someone then?
Somehow... your avatar change says 'No' confused:
I cannot find my moggy anywhere, I know it is around here somewhere, :hmh:someone has been messing with my filling system.evil: I have some gory spider photos, anyone mind if I change from Puss to Spider?
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What on earth have you lot been up to! I've had reported posts! How is that possible I thought, we are all friends here, trusted individuals. Now, I see that you lot have all got a bit over excited. Can I not even dig my garden for a day without worrying about you all?!?! :)
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Awww! Wuz you gonna be nice to someone then?
Somehow... your avatar change says 'No' confused:
I cannot find my moggy anywhere, I know it is around here somewhere, :hmh:someone has been messing with my filling system.evil: I have some gory spider photos, anyone mind if I change from Puss to Spider?
Hahahahahahahahaha! lol:
Anybody mind if you change your name to ’cannot use the quote function’? point:
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[
I’ll smite you again (in an hour) for changing your avatar… Angry9:
If you e-mail me the original picture I’ll applaud you later…
It's a bit difficult, the only full size photo I have was taken after the removal of the 2 little white triangles leaving only one strategically place white triangle, if you know what I mean. redface:
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Awww! Wuz you gonna be nice to someone then?
Somehow... your avatar change says 'No' confused:
I cannot find my moggy anywhere, I know it is around here somewhere, :hmh:someone has been messing with my filling system.evil: I have some gory spider photos, anyone mind if I change from Puss to Spider?
Hahahahahahahahaha! lol:
Anybody mind if you change your name to ’cannot use the quote function’? point:
Bugger... noooo:
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[
I’ll smite you again (in an hour) for changing your avatar… Angry9:
If you e-mail me the original picture I’ll applaud you later…
It's a bit difficult, the only full size photo I have was taken after the removal of the 2 little white triangles leaving only one strategically place white triangle, if you know what I mean. redface:
I understand… noooo:
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Ummm what was the avatar? Have I missed something vital?!?!
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Ummm what was the avatar? Have I missed something vital?!?!
Oh yes? you missed a pair of breasts that put yours to shame? point:
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Should I be worried? Is my crown being threatened? Should I play with my new banning powers?
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Should I be worried? Is my crown being threatened? Should I play with my new banning powers?
Extremely worried! point:
Very threatened! surrender:
No. noooo:
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Postscript:
How far can you lower a rope down a hole?
No tricks.
I’d imagine the limitation would be the length of your arm? whistle:
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< Shrugs Shoulders>
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< Shrugs Shoulders>
lol:
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Postscript:
How far can you lower a rope down a hole?
No tricks.
I’d imagine the limitation would be the length of your arm? whistle:
No the limitation is on the length of the rope of course!
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Postscript:
How far can you lower a rope down a hole?
No tricks.
I’d imagine the limitation would be the length of your arm? whistle:
No the limitation is on the length of the rope of course!
Or the depth of the well.
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Postscript:
How far can you lower a rope down a hole?
No tricks.
I’d imagine the limitation would be the length of your arm? whistle:
No the limitation is on the length of the rope of course!
Hmmmm... we'll see... clock:
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Postscript:
How far can you lower a rope down a hole?
No tricks.
So, what is the answer? cussing:
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Postscript:
How far can you lower a rope down a hole?
No tricks.
So, what is the answer? cussing:
I refer the not so honourable gentleman to the answer I gave earlier. Although it would be nice to have it confirmed as correct. How about it?
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Ummm what was the avatar? Have I missed something vital?!?!
Twas but an old photo of mine. Nothing vital.
I did add a message undernath it, that if it made Holly prickly I would remove it. scared:
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Postscript:
How far can you lower a rope down a hole?
No tricks.
So, what is the answer? cussing:
I refer the not so honourable gentleman to the answer I gave earlier. Although it would be nice to have it confirmed as correct. How about it?
See ~ Yuh jest can't trust a cat
(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fcsmt.msstate.edu%2Fhtml%2FCSEM%2Fimages%2Fsnoopy.gif&hash=3ad936fb66d5549601423efb17c1b34eb291282b)
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I refer the not so honourable gentleman to the answer I gave earlier. Although it would be nice to have it confirmed as correct. How about it?
What, this one?
As far as I can work out using basic maths, the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break.
Hahahahahahahaha! point:
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As far as I can work out using basic maths, the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break.
Hahahahahahahaha! point:
Bah, I will get you for that just you wait and see. evil: How did you do that? Shall I switch to that username? Can I have 2 id's? So many questions.
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As far as I can work out using basic maths, the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break.
Hahahahahahahaha! point:
Bah, I will get you for that just you wait and see. evil: How did you do that? Shall I switch to that username? Can I have 2 id's? So many questions.
Bring back the bikini, bring back the bikini, bring back the bikini, bring back the bikini, bring back the bikini... cussing:
(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Frds.yahoo.com%2F_ylt%3DA9ibyGY_NTZGyUEBOnijzbkF%3B_ylu%3DX3oDMTBsMW5yM3VoBHNlYwNwcm9mBHZ0aWQDSTA2Nl84OA--%2FSIG%3D12fkiabc7%2FEXP%3D1178044095%2F%2A%2Ahttp%253A%2F%2Fwww.animationusa.com%2Fpicts%2Fhbpict%2F3_Most-Top-Cat.jpg&hash=ca0b63214e2af15a74abce2e31e967928aea91ef)
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Anyway where's this one got to?
(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fi38.photobucket.com%2Falbums%2Fe121%2Fnanathea%2Fgarfield.jpg&hash=3d2f1ee88ecf97f3627785a36dc910aeb7050718)
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I've had an idea ~ let's run a test.
http://www.snaithprimary.eril.net/rhyme5.htm
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Anyway where's this one got to?
(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fi38.photobucket.com%2Falbums%2Fe121%2Fnanathea%2Fgarfield.jpg&hash=3d2f1ee88ecf97f3627785a36dc910aeb7050718)
Well, I think the webcam there shows the status of our moderator? noooo:
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I've had an idea ~ let's run a test.
http://www.snaithprimary.eril.net/rhyme5.htm
What should we say to Tommy?
Drop it! point:
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I've had an idea ~ let's run a test.
http://www.snaithprimary.eril.net/rhyme5.htm
What should we say to Tommy?
Drop it! point:
lol: You have a webcam in the study.......... redface: Where is my towel.
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I've had an idea ~ let's run a test.
http://www.snaithprimary.eril.net/rhyme5.htm
What should we say to Tommy?
Drop it! point:
lol: You have a webcam in the study.......... redface: Where is my towel.
Too late. eyes:
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Too late. eyes:
redface:
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(https://www.virtual-pub.com/SMF/proxy.php?request=http%3A%2F%2Fcapefeare.com%2Fsnoopycomic.jpg&hash=46032cd4d37ebc94ade0bd31f7b0b5b7b188b9b7)
Good Night All.
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Sorry they jiggle on my page, but not on here. redface:
As far as I can work out using basic maths, the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break. lol:
Smartarse....... thumbsup:
So... What about the Aeroplane then?
I wish people that accuse other people of not reading other peoples previous post's would er... look at the previous post's - Um redface: I think that's what I mean, noooo: anyway I already said it! spider: Earlier, that is...
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WHAT IS THE ANSWER !!!!!!
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WHAT IS THE ANSWER !!!!!!
the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break.
OK?
Or were you referring to the aeroplane?
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The aeroplane. redface:
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I don't think he can remember ~ last seen "sampling" the new guest ales rolleyes:
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the distance would depend on the breaking strain of the rope. Once the length of rope down the hole equals the weight of the breaking strain, then it would ....er...break.
OK?
Or were you referring to the aeroplane?
That?s a stupid answer!
The question was how far could you (me) lower a rope down a hole or well or something?
Fact is, I couldn?t hold a length of rope that was soooo long that it broke under it on weight.
I think my answer was best. whistle:
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and the aeroplane? whip:
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and the aeroplane? whip:
.... could not take off due to lack of forward momentum generating lift.
OK?
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and the aeroplane? whip:
.... could not take off due to lack of forward momentum generating lift.
OK?
Agreed... although I have been arguing about it here: -
http://www.simplemachines.org/community/index.php?topic=167644.0
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and the aeroplane? whip:
.... could not take off due to lack of forward momentum generating lift.
OK?
So the two cancelled each other out? confused1:
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and the aeroplane? whip:
.... could not take off due to lack of forward momentum generating lift.
OK?
rolleyes:
So the two cancelled each other out? confused1:
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and the aeroplane? whip:
.... could not take off due to lack of forward momentum generating lift.
OK?
So the two cancelled each other out? confused1:
I believe so.
But the barman spoke too quietly to make out what he said. confused:
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and the aeroplane? whip:
.... could not take off due to lack of forward momentum generating lift.
OK?
So the two cancelled each other out? confused1:
I believe so.
But the barman spoke too quietly to make out what he said. confused:
I said..
Oh, I see... redface:
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I'm not so sure now clock: I am becoming persuaded by the argument of the motive force pushing against the air and not the moving runway.
It could - may - possibly - arguably be that the 'plane would acheive forward momentum independently of the wheel speed.
There again, if the wheels were rotating twice as fast then the runway would accelerate to twice the speed to match it. and it would - might - counter the additional effort.
Einstein was very clear about equal and opposite reactions, but he never mentioned wheels... rubschin:
Two asprins please Barman, and a bowl of milk.
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Just imagine for a moment that instead of the conveyor control being automatic, a little man adjusts it at will to different speeds.
At the start, both the aircraft and conveyor are stationary.
Then, the pilot starts the engines and begins to taxi forward on the conveyor at 5mph. His little speedometer in the cockpit shows 5mph while the airspeed indicator also shows 5mph.
Spotting this, the man turns on the conveyor in the opposite direction at 5mph (shrewd guy).
High up in the cockpit, the pilots speedometer still shows 5mph but as the ?ground? is moving backwards at the same speed, the air speed indicator shows zero ? he is stationary with respect to the ground.
Frustrated, the pilot cranks open the throttles further and accelerates to 15mph. Now his little speedometer shows 15mph as that is the speed that he is travelling along the conveyor. Unfortunately, the conveyor is travelling at 5mph is the opposite direction so his air speed indicator only shows 10mph.
Seeing the aircraft get away from him down towards the end of the conveyor, the little man cranks his speed wheel up to 15mph.
Back in the cockpit, the speedometer still shows that the ?plane is travelling at 15mph down the conveyor, but as the conveyor is now going at 15mph in the opposite direction, the air speed indicator drops to zero again.
I can continue, but you get the idea?
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I wouldn't fly with them. They should all get off and go to the EasyJet desk.
Problem solved drumroll:
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Just imagine for a moment that instead of the conveyor control being automatic, a little man adjusts it at will to different speeds.
At the start, both the aircraft and conveyor are stationary.
Then, the pilot starts the engines and begins to taxi forward on the conveyor at 5mph. His little speedometer in the cockpit shows 5mph while the airspeed indicator also shows 5mph.
Spotting this, the man turns on the conveyor in the opposite direction at 5mph (shrewd guy).
High up in the cockpit, the pilots speedometer still shows 5mph but as the ?ground? is moving backwards at the same speed, the air speed indicator shows zero ? he is stationary with respect to the ground.
Frustrated, the pilot cranks open the throttles further and accelerates to 15mph. Now his little speedometer shows 15mph as that is the speed that he is travelling along the conveyor. Unfortunately, the conveyor is travelling at 5mph is the opposite direction so his air speed indicator only shows 10mph.
Seeing the aircraft get away from him down towards the end of the conveyor, the little man cranks his speed wheel up to 15mph.
Back in the cockpit, the speedometer still shows that the ?plane is travelling at 15mph down the conveyor, but as the conveyor is now going at 15mph in the opposite direction, the air speed indicator drops to zero again.
I can continue, but you get the idea?
Yeah Yeah! I get it! And for a while I accepted it. But then got to an advanced stage of thought.... hence the headache....
The argument you put is compelling - for a car. And by that, I mean a vehicle that achieves it's propulsion through its wheels and therefore relies totally on its adhesion to the surface for motion. Thus +10 and - 10 = zero.
However, an aircraft does not rely on ground adhesion for its propulsion, indeed if it did then as soon as left contact with the runway it would stop - or at least begin to slow down as it drive train is broken.
So, to fly the drive has to be independant of the ground. And if it is independant of the ground then it matters not what its ground speed is. Imagine an aircraft flying at an airspeed of 100mph WITH a wind of 30mph then its groundspeed would be 130mph, however if it was flying INTO the same wind its airspeed would still be 100mph but its groundspeed would by only 70mph (less the 30mph blowing the other way) so the difference would be 60mph relative to the ground. Now here's the interesting bit......
Travelling at 100mph into a 30mph headwind leaves it flying at 70mph ground speed means that if the plane reduced its forward speed to 30mph then it would simply drop onto the runway because its groundspeed is 0.
All this means that the speed relationship between the aircraft and the runway is dynamic and not mechanical therefore the takeoff speed is measured in the forward air pressure exerted and not to its relationship to the ground.
If it can land stationary at 30mph then it can take off stationary by the same relative air forces at work and the ground speed counts for nothing, it's a distraction.
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Oh dear oh dear, I shall be smoted for this for sure... noooo:
It matters not if the propulsion system is through the wheels or via jet engines mounted on the wings? The fact remains that for the aircraft to lift off (assuming conventional flight and not rocket flight, VTO, etc.) it has to achieve air flow over the wings ? a 747-400 needs 180mph before the wings generate enough lift its maximum take off weight of 875,000lbs off the ground.
In the scenario described the treadmill exactly matches the speed of the ?plane so it will never achieve this. However fast the wheels are travelling in relation to the treadmill the aircraft no forward speed in relation to the earth and therefore no air flow over the wings.
The only way that an aircraft in this situation could take off is if a sudden storm blew up and provided a ?wind? over the wings equivalent to the take off speed required.
Travelling at 100mph into a 30mph headwind leaves it flying at 70mph ground speed means that if the plane reduced its forward speed to 30mph then it would simply drop onto the runway because its groundspeed is 0.
No. It depends on the ?stall speed? of the aircraft. If it is 30mph or lower it would continue to fly even though the ground speed had reduced to zero. Indeed it is even possible for an aircraft to fly backwards with respect to the ground into a strong wind.
All this means that the speed relationship between the aircraft and the runway is dynamic and not mechanical therefore the takeoff speed is measured in the forward air pressure exerted and not to its relationship to the ground.
No. In flight the speed over the ground is totally irrelevant and can even be negative as I described above. To achieve flight however the aircraft needs to gain forward momentum with respect to the ground and the treadmill cancels this out. The only way to overcome this would be to add so much power to the aircraft that the friction between the wheels and the conveyor was overcome and the aircraft slid down the conveyor to take off. However, the amount of power required would be so vast that a conventional aircraft would simply be destroyed by it.
If it can land stationary at 30mph then it can take off stationary by the same relative air forces at work and the ground speed counts for nothing, it's a distraction.
No. The thrust available to a conventional (non military) aircraft is insufficient to overcome its mass in that way. A 747-400 for instance has a MTO weight of 875,000lbs but only 253,200lbs of thrust available. The engines overcome the frictional forces and move the aircraft forward along the ground ? thus achieving air flow over the wings and eventual take off.
The Harrier has a maximum take of weight for vertical take off (VTO) of 18,950lb and a maximum thrust from the Pegasus engine of 23,800lb. I.e. the thrust is grater than the weight and it can lift it straight off the ground. In a rolling take off (where the wings are used to generate lift as the aircraft travels forwards) the maximum take off weight is increased to 31,000lb.
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Contrary to popular belief, aircraft are sustained in the air by faith alone. One determined cynic can, in theory, ground an entire 747. In practice, the professional commitment of aircrew to the continued flight of the plane keeps it in the air. A moment of self-examination on the part of the pilot, however, can be disastrous. I thought I would share that with you because your debate is very very silly, and you should all go and stand in the corner whip:
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Contrary to popular belief, aircraft are sustained in the air by faith alone. One determined cynic can, in theory, ground an entire 747. In practice, the professional commitment of aircrew to the continued flight of the plane keeps it in the air. A moment of self-examination on the part of the pilot, however, can be disastrous. I thought I would share that with you because your debate is very very silly, and you should all go and stand in the corner whip:
lol: lol: hehehehe...
I shall go and post that on all the sites debating it. whistle:
I trust there is no copyright fee involved? noooo:
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Go for it big boy!
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Go for it big boy!
I applaud your positive attitude?
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Stop complicating the issue with characteristics of hugely differing aircraft where the speed and mass vary enormously but the basic principle remains the same, namely the airflow across the wing surface causes the lift to overcome gravitational forces.
Most of your argument agrees with mine especially with consideration to the airspeed compared to groundspeed. They have no common factor.
A stationary aircraft facing a headwind speed exceeding its lift factor will take off. Conversely an aircraft facing downwind would never take off. Tat is the reason why aircraft always face into the wind to take off, thus reducing the effort required.
It is the mind boggling aspect of Einstein?s equal and opposite reaction that decides the issue.
All agreed so far?
Despite all of the variables, the issue is; can the aircraft achieve the airflow needed to generate the lift required?
Reason against: As the wheel rotation is always countered there will be no forward motion therefore no lift will occur.
Reason for: As the thrust is exerted onto air and not the ground the wheel speed is immaterial.
Damn you! You are definitely going to be smitten.
The equation stands in my mind as follows:
If the wheels are in a permanent state of equal speed with the runway then the physical state is exactly the same as if the brakes were applied to the wheels.
As an ordinary aircraft does not have sufficient power to overcome the braking effort then it would indeed seem that motion would be impossible, and as such, air flow would not occur. (Excepting wind speed) and so, lift is not attainable.
I must therefore reconsider my position ? at least until I think of something else. evil:
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A stationary aircraft facing a headwind speed exceeding its lift factor will take off. Conversely an aircraft facing downwind would never take off. Tat is the reason why aircraft always face into the wind to take off, thus reducing the effort required.
No. If you think about it? Once the airspeed over the wing (from the headwind) is sufficient to overcome its mass it would indeed momentarily lift off the ground but then be blown backwards?
Only if the aircraft were tethered would it be able to lift upwards in a strong wind.
Irrelevant I know but I thought I?d mention it?
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A stationary aircraft facing a headwind speed exceeding its lift factor will take off. Conversely an aircraft facing downwind would never take off. That is the reason why aircraft always face into the wind to take off, thus reducing the effort required.
No. If you think about it? Once the airspeed over the wing (from the headwind) is sufficient to overcome its mass it would indeed momentarily lift off the ground but then be blown backwards?
Only if the aircraft were tethered would it be able to lift upwards in a strong wind.
Irrelevant I know but I thought I?d mention it?
Not if it were under full power and only restrained by the wheel resistance. As soon as the craft leaves the ground the wheel effect will cease and normal forward momentum - relational to the air flow - would commence. You said yourself that an aircraft can fly 'backwards' in relation to the ground. so as soon as the ground effect is removed it leaves the equation. as long as lift is maintained it will fly. Lift is defined by adequate airflow not forward momentum.
Using your model a glider would not work.
Seeing as you want to argue about something............. :)
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What if the little man controlling the little wheel on the conveyor goes for a p*ss?
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A stationary aircraft facing a headwind speed exceeding its lift factor will take off. Conversely an aircraft facing downwind would never take off. That is the reason why aircraft always face into the wind to take off, thus reducing the effort required.
No. If you think about it? Once the airspeed over the wing (from the headwind) is sufficient to overcome its mass it would indeed momentarily lift off the ground but then be blown backwards?
Only if the aircraft were tethered would it be able to lift upwards in a strong wind.
Irrelevant I know but I thought I?d mention it?
Not if it were under full power and only restrained by the wheel resistance. As soon as the craft leaves the ground the wheel effect will cease and normal forward momentum - relational to the air flow - would commence. You said yourself that an aircraft can fly 'backwards' in relation to the ground. so as soon as the ground effect is removed it leaves the equation. as long as lift is maintained it will fly. Lift is defined by adequate airflow not forward momentum.
Using your model a glider would not work.
Seeing as you want to argue about something............. :)
But, but but... you didn?t say the engines were running! point:
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rubschin: Shouldn't somebody report these two to Admin?
Bugger! They are Admin tunble:
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I don't understand what is happening so I don't really think I can become involved. eeek:
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I don't understand what is happening so I don't really think I can become involved. eeek:
That's never ever stopped any woman getting involved.
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I don't understand what is happening so I don't really think I can become involved. eeek:
That's never ever stopped any woman getting involved.
There are limits. For instance, I don't become embroiled in football disagreements either. However, as a general thing you are right. redface:
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whacky068
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whacky068
Stop sneaking these foreign emoticon icons in when I'm not looking whip:
The engines wern't running, they were stationary along with the rest of the aeroplane drumroll:
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whacky068
Stop sneaking these foreign emoticon icons in when I'm not looking whip:
The engines wern't running, they were stationary along with the rest of the aeroplane drumroll:
Then it wouldn't fly with a strong headwind. whacky082
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whacky068
Stop sneaking these foreign emoticon icons in when I'm not looking whip:
The engines wern't running, they were stationary along with the rest of the aeroplane drumroll:
Then it wouldn't fly with a strong headwind. whacky082
Just stop it. You are not intimidating me with whacky wotsits! The engines were stationary but the props weren't!
They were whizzing around flat out! whacky007 Now THAT'S better :)
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whacky068
Stop sneaking these foreign emoticon icons in when I'm not looking whip:
The engines wern't running, they were stationary along with the rest of the aeroplane drumroll:
Then it wouldn't fly with a strong headwind. whacky082
Just stop it. You are not intimidating me with whacky wotsits! The engines were stationary but the props weren't!
They were whizzing around flat out! whacky007 Now THAT'S better :)
sleep017