RE: Can It Take Off??  
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RE: Can It Take Off?? - 12/3/2005 2:44:47 PM   
dick Hanson



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Status: offline 		Even Libby saw thru this one -

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RE: Can It Take Off?? - 12/3/2005 3:11:25 PM   
air mail rcu


 

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Status: offline 		If the plane would take off then we can have smaller airports. No catapults on carriers. And the Japanese didn't need to build and entire Inland for a airport. All we need are some large belt sanders. And they really don't need to be that big. Just one under each wheel.

One question: If we are walking on a people mover in the opposite direction and the people mover is matching our forward speed do we ever get to where we are going?

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RE: Can It Take Off?? - 12/3/2005 4:11:03 PM   
Phlip



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quote:

Imagine an airplane is on the beginning of a massive conveyor belt, as wide and as long as a runway, and intends to take off. The conveyer belt is designed to exactly match the speed of the wheels at any given time, moving in the opposite direction of rotation.
There is no wind.

Can the plane take off?

quote:


All we need are some large belt sanders. And they really don't need to be that big. Just one under each wheel.


No fair changing the rules of the puzzle! The original didn't say anything about belt sanders! If you sand a hole in the tires, how will the plane roll? And how will you keep from ruining the CV joints and ball joints as the plane falls down off the sanders?
Just put it in 4WD and gun it. It'll go!



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RE: Can It Take Off?? - 12/3/2005 4:30:06 PM   
Liberator


 

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Status: offline 		That makes me more nervous than you can imagine. The watching part that is.


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RE: Can It Take Off?? - 12/3/2005 4:43:44 PM   
3dbob37n


 

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Status: offline 		OK, Hanson, you can't figure it out either and are copping out.

Why don't we meet at O'Hare and we'll borrow an L-1011 and face it in the direction the planet turns and see if it will take off? I'll take the left seat. Hanson, you run the computer to record our progress. Bent Wings, since you started all this, you get your butt back in the galley and get the food ready.

This is the only way we can solve this problem because it seems no one knows the answer.
So much for all you aeronautical genius's. Bah Humbug!


3dbob

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RE: Can It Take Off?? - 12/3/2005 6:04:06 PM   
air mail rcu


 

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quote:

ORIGINAL: Phlip
Just put it in 4WD and gun it. It'll go!



Sometimes you have to rock it back and forth.

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RE: Can It Take Off?? - 12/3/2005 7:31:45 PM   
dick Hanson



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Status: offline 		Sure -I answered it 3 time --Libby also said you guys are barking up the wrong tree - (always watching )
the answer -- the wheels on the belt mean -Zippo- nada - keine-nothing - the question is simply a trick question --- the aircraft taking off has nothing to do with the wheels rotation
The ONLY reason land based aircraft have wheels is to reduce the friction from forward motion.
sheesh---
first aircraft had skids -I remember helping Wil and Orvie back there at the big sandhill---

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RE: Can It Take Off?? - 12/3/2005 7:36:01 PM   
David Cutler



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quote:

the wheels on the belt mean -Zippo- nada - keine-nothing


Yep!



-David C.

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RE: Can It Take Off?? - 12/4/2005 8:38:10 PM   
bentwings


 

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this is going to be a long flight with you guys driving. I was thinking of a load of Omaha Steaks and Idaho potato steak fries.. Think this will affect the take off??

BTW I'm doing some durability testing involving needle roller bearings at work. They might work pretty well in the conveyor rollers. They will probably need them with the ground speed we'll need to get off with all those steaks aboard.

I wonder if we should bring along some "black crow" for those unbelievers. I heard slightly rare is the preferred temp.

bentwings

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RE: Can It Take Off?? - 12/4/2005 8:46:20 PM   
David Cutler



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quote:

Brain Teaser


It only teases the brain if the difference between airspeed and groundspeed isn't understood.

It's airspeed that provides lift, and the prop is working on the air to increase airspeed not the ground.

Groundspeed, however it is looked at, doesn't enter into it.

In fact, I am sure there are a lot of people here who have landed a plane at a negative groundspeed (that is, travelling backwards) when the windspeed exceeds the required landing airspeed.

-David C.

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RE: Can It Take Off?? - 12/4/2005 8:58:06 PM   
Tall Paul



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F=ma.
The plane flies.

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RE: Can It Take Off?? - 12/4/2005 9:15:52 PM   
dick Hanson



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Status: offline 		FMA - I thot was an electric motor sales group.
This "quiz" is more in the nature of a basic IQ test than a question of aerodynamics.

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RE: Can It Take Off?? - 12/4/2005 10:49:45 PM   
Flyfalcons



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Status: offline 		The problem is for the airplane to take off, it needs to be moving forward (no wind). If the plane is moving forward, then the belt would not be spinning at an equal rate to the tires.

Kind of a PITA question. Sort of like asking, if God is capable of doing or creating anything, can He create a rock so big that He can't move it?

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RE: Can It Take Off?? - 12/4/2005 11:20:46 PM   
dick Hanson



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Status: offline 		OK-what do the wheels turning have to do with the plane moving forward?
On an airplane - wheels do one thing - reduce friction /resistance-that's it
If the wheels were simply made of ice and had NO friction/resistance to the belt/ground/grass what have you-what would the effect be?
You can study this one as much as you want but -there is simply no involvement with the wheels -except removing friction
The "question" is simply an exercize in logic- no math - no formulas required

< Message edited by dick Hanson -- 12/4/2005 11:21:50 PM >

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RE: Can It Take Off?? - 12/4/2005 11:24:35 PM   
David Cutler



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Status: offline 		The speed of the belt, the revolving speed of the wheels, and anything else that doesn't take part in the change in airspeed has nothing to do with whether the plane flies or not. As soon as V1 speed is achieved, however it's achieved, the plane will fly.

Moving belts, spinning wheels have nothing to do with it. If there's enough air passing over the wing to provide lift it flies. If there isn't, it doesn't. End of subject.

-David C.

< Message edited by David Cutler -- 12/4/2005 11:31:26 PM >

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RE: Can It Take Off?? - 12/4/2005 11:36:55 PM   
David Cutler



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quote:

ORIGINAL: dick Hanson

OK-what do the wheels turning have to do with the plane moving forward?
On an airplane - wheels do one thing - reduce friction /resistance-that's it
If the wheels were simply made of ice and had NO friction/resistance to the belt/ground/grass what have you-what would the effect be?
You can study this one as much as you want but -there is simply no involvement with the wheels -except removing friction
The "question" is simply an exercize in logic- no math - no formulas required


100% agree.

-David C.

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RE: Can It Take Off?? - 12/4/2005 11:40:28 PM   
David Cutler



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quote:

ORIGINAL: Flyfalcons

The problem is for the airplane to take off, it needs to be moving forward (no wind). If the plane is moving forward, then the belt would not be spinning at an equal rate to the tires.


The belt could be travelling at 1,000,000 mph or zero, and the wheels spinning at 1,000,000,000 rpm or zero. It makes no difference to the airspeed of the plane, and therefore the air passing over the wing.

You are confusing groundspeed with airspeed still.

-David C.



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