Tippmann Paintball Homepage
Forum Home Forum Home > News And Views > Thoughts and Opinions
  New Posts New Posts
  FAQ FAQ  Forum Search   Register Register  Login Login

Interesting Debate for the Physics Savy
 Post Reply Post Reply Page  123 5>
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
carl_the_sniper View Drop Down
Platinum Member
Platinum Member
Avatar
Strike 1 - 7/29, Bad Linky

Joined: 08 April 2006
Location: Canada
Status: Offline
Points: 11259 		Post Options Post Options   Thanks (0) Thanks(0)   Quote carl_the_sniper Quote  Post ReplyReply Direct Link To This Post Topic: Interesting Debate for the Physics Savy
    Posted: 29 January 2008 at 10:21pm
I'm not sure if this will work on this forum but...

This is a hypothetical situation that has been going around a lot of aviation and RC aviation forums. There has been a lot of debate as to what would happen and I'd like to know what you guys think.

The story goes:

An airplane is on a large treadmill pointing in a reverse direction of the treadmill.

The treadmill has been engineered to match the exact speed of the airplane but backwards. This will mean that in relation to the ground, the airplane will not move and will be moving at 0 miles per hour in relation to the ground)

The question is, will the airplane fly?
Back to Top
Hysteria View Drop Down
Platinum Member
Platinum Member
Avatar
Strike 2 - Language, 9/25

Joined: 02 February 2005
Location: United States
Status: Offline
Points: 4364 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Hysteria Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:24pm
No.

Lift is created when air is displaced by the wings.  If there is no air being displaced by the wings there is no lift, thus the airplane will not fly.

At least, that is my uneducated guess.  I did, after all, drop out of Physics after a month or two last semester.
Back to Top
usafpilot07 View Drop Down
Moderator Group
Moderator Group
Avatar
FreeEnterprise's #1 Fan & Potty Mouth

Joined: 31 August 2004
Location: Tokelau
Status: Offline
Points: 4626 		Post Options Post Options   Thanks (0) Thanks(0)   Quote usafpilot07 Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:25pm
LOLMYTHBUSTERS?
Back to Top
Snake6 View Drop Down
Platinum Member
Platinum Member
Avatar
Outranked by guitarguy?

Joined: 11 September 2003
Location: United States
Status: Offline
Points: 11229 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Snake6 Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:26pm
Originally posted by usafpilot07 usafpilot07 wrote:

LOLMYTHBUSTERS?

And as far as I see it will not fly...
Back to Top
carl_the_sniper View Drop Down
Platinum Member
Platinum Member
Avatar
Strike 1 - 7/29, Bad Linky

Joined: 08 April 2006
Location: Canada
Status: Offline
Points: 11259 		Post Options Post Options   Thanks (0) Thanks(0)   Quote carl_the_sniper Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:28pm
Originally posted by Hysteria Hysteria wrote:

No.Lift is created when air is displaced by the wings.  If there is no air being displaced by the wings there is no lift, thus the airplane will not fly.At least, that is my uneducated guess.  I did, after all, drop out of Physics after a month or two last semester.


What about the air displaced by the propeller?

Originally posted by usafpilot07 usafpilot07 wrote:

LOLMYTHBUSTERS?


Mystbusters is crap. They half ass and screw up so many things.
Back to Top
Susan Storm View Drop Down
Gold Member
Gold Member
Avatar
Shot at Love Contestant

Joined: 13 July 2007
Location: United States
Status: Offline
Points: 1352 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Susan Storm Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:29pm

Generally speaking, no.  Lift is created by the upward suction of the air above the wings, which is created by airspeed.

No airspeed = no lift = no fly.

Some turbine placements might themselves create some lift, but that would be cheating.
"No society can surely be flourishing and happy, of which the far greater part of the members are poor and miserable."
Back to Top
Tolgak View Drop Down
Platinum Member
Platinum Member
Avatar
Master of MSPaint and bri's Daddy

Joined: 12 July 2002
Location: BEHIND YOU!
Status: Offline
Points: 1239486 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Tolgak Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:34pm
You explanations are flawed.

The wheels do not generate the power, the prop/jet/rocket/fan does. The only thing you'll accomplish is making the wheels rotate twice as fast. The plane will take off a bit slower than normal, only because the wheels will be contacting the runway which will create considerable drag.


Edited by Tolgak - 29 January 2008 at 10:41pm
Back to Top
Styro Folme View Drop Down
Platinum Member
Platinum Member

Strike 1 - Rules 1 and 2

Joined: 28 February 2005
Location: United States
Status: Offline
Points: 8086 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Styro Folme Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:36pm
Originally posted by carl_the_sniper carl_the_sniper wrote:

Originally posted by Hysteria Hysteria wrote:

No.Lift is created when air is displaced by the wings.  If there is no air being displaced by the wings there is no lift, thus the airplane will not fly.At least, that is my uneducated guess.  I did, after all, drop out of Physics after a month or two last semester.


What about the air displaced by the propeller?

Originally posted by usafpilot07 usafpilot07 wrote:

LOLMYTHBUSTERS?


Mystbusters is crap. They half ass and screw up so many things.
i dare you to make a better show.
X
Back to Top
Susan Storm View Drop Down
Gold Member
Gold Member
Avatar
Shot at Love Contestant

Joined: 13 July 2007
Location: United States
Status: Offline
Points: 1352 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Susan Storm Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:36pm
Tolga is smarter than us.
"No society can surely be flourishing and happy, of which the far greater part of the members are poor and miserable."
Back to Top
Glassjaw View Drop Down
Platinum Member
Platinum Member
Avatar
Took down Mike Tyson

Joined: 13 July 2004
Location: Philly
Status: Offline
Points: 6454 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Glassjaw Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:47pm
Originally posted by Tolgak Tolgak wrote:

You explanations are flawed.

The wheels do not generate the power, the prop/jet/rocket/fan does. The only thing you'll accomplish is making the wheels rotate twice as fast. The plane will take off a bit slower than normal, only because the wheels will be contacting the runway which will create considerable drag.


I was going to say this.

tl:dr, the plane will take off.
The desire for polyester is just to powerful.
Back to Top
Snake6 View Drop Down
Platinum Member
Platinum Member
Avatar
Outranked by guitarguy?

Joined: 11 September 2003
Location: United States
Status: Offline
Points: 11229 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Snake6 Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:58pm
Originally posted by Styro Folme Styro Folme wrote:

Originally posted by carl_the_sniper carl_the_sniper wrote:

Originally posted by Hysteria Hysteria wrote:

No.Lift is created when air is displaced by the wings.  If there is no air being displaced by the wings there is no lift, thus the airplane will not fly.At least, that is my uneducated guess.  I did, after all, drop out of Physics after a month or two last semester.


What about the air displaced by the propeller?

Originally posted by usafpilot07 usafpilot07 wrote:

LOLMYTHBUSTERS?


Mystbusters is crap. They half ass and screw up so many things.
i dare you to make a better show.

Agreed. Mythbusters is very entertaining. That show with Bear Grylls is crap.
Back to Top
Tolgak View Drop Down
Platinum Member
Platinum Member
Avatar
Master of MSPaint and bri's Daddy

Joined: 12 July 2002
Location: BEHIND YOU!
Status: Offline
Points: 1239486 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Tolgak Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 10:59pm
Originally posted by Glassjaw Glassjaw wrote:

Originally posted by Tolgak Tolgak wrote:

You explanations are flawed.

The wheels do not generate the power, the prop/jet/rocket/fan does. The only thing you'll accomplish is making the wheels rotate twice as fast. The plane will take off a bit slower than normal, only because the wheels will be contacting the runway which will create considerable drag.


I was going to say this.

tl:dr, the plane will take off.


Well, there's no guarantee. It will take considerably more power because of the drag that takes place. However, as more thrust is put out, you will start to overcome that drag and there's a good chance you'll be able to get up (unless your wheels explode or the plane tips the wrong way).
Back to Top
Jack Carver View Drop Down
Gold Member
Gold Member
Avatar

Joined: 07 February 2006
Status: Offline
Points: 1653 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack Carver Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 11:02pm
Read it again:
Originally posted by carl_the_sniper carl_the_sniper wrote:

The treadmill has been engineered to match the exact speed of the airplane but backwards. This will mean that in relation to the ground, the airplane will not move

The airplane never moves, so no high-speed air past the wings (other than maybe a little bit if you've got propellers), no lift, no takeoff.
Back to Top
carl_the_sniper View Drop Down
Platinum Member
Platinum Member
Avatar
Strike 1 - 7/29, Bad Linky

Joined: 08 April 2006
Location: Canada
Status: Offline
Points: 11259 		Post Options Post Options   Thanks (0) Thanks(0)   Quote carl_the_sniper Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 11:04pm
Originally posted by Susan Storm Susan Storm wrote:

Generally speaking, no.  Lift is created by the upward suction of the air above the wings, which is created by airspeed.


No airspeed = no lift = no fly.


Some turbine placements might themselves create some lift, but that would be cheating.



Originally posted by Tolgak Tolgak wrote:



You explanations are flawed.The wheels do not generate the power, the prop/jet/rocket/fan does. The only thing you'll accomplish is making the wheels rotate twice as fast. The plane will take off a bit slower than normal, only because the wheels will be contacting the runway which will create considerable drag.


Exactly, you can't think of it like a car because the wheels don't produce thrust.

My personaly opinion is that it is possible but only on certain aircraft designs with certain engine types. A front mounted prop would work. A rear mounted prop or jet engine would not.

Originally posted by Styro Folme Styro Folme wrote:


Originally posted by carl_the_sniper carl_the_sniper wrote:

Originally posted by Hysteria Hysteria wrote:

No.Lift is created when air is displaced by the wings.  If there is no air being displaced by the wings there is no lift, thus the airplane will not fly.At least, that is my uneducated guess.  I did, after all, drop out of Physics after a month or two last semester.


What about the air displaced by the propeller?

Originally posted by usafpilot07 usafpilot07 wrote:

LOLMYTHBUSTERS?


Mystbusters is crap. They half ass and screw up so many things.
i dare you to make a better show.


It's not hard to make a show that actually does proper experiments instead of taking short cuts.

Back to Top
carl_the_sniper View Drop Down
Platinum Member
Platinum Member
Avatar
Strike 1 - 7/29, Bad Linky

Joined: 08 April 2006
Location: Canada
Status: Offline
Points: 11259 		Post Options Post Options   Thanks (0) Thanks(0)   Quote carl_the_sniper Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 11:05pm
Originally posted by Jack Carver Jack Carver wrote:

Read it again:
Originally posted by carl_the_sniper carl_the_sniper wrote:

The treadmill has been engineered to match the exact speed of the airplane but backwards. This will mean that in relation to the ground, the airplane will not move
The airplane never moves, so no high-speed air past the wings (other than maybe a little bit if you've got propellers), no lift, no takeoff.


The propeller moves more than a little air.



Edited by carl_the_sniper - 29 January 2008 at 11:07pm
Back to Top
Jack Carver View Drop Down
Gold Member
Gold Member
Avatar

Joined: 07 February 2006
Status: Offline
Points: 1653 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack Carver Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 11:07pm
Ok, so since the jets/prop will continue to give thrust, the plane's speed on the treadmill will rise until the wheels overheat, explode and everybody inside dies as the plane goes belly-down onto a 700 mph giant treadmill.

/hugemanatee

edit: but it only moves a lot of air over a small part of the wing. The plane works because the entire wing causes lift. Your props would have to be spinning like a mofo to cause enough lift to get it in the air.


Edited by Jack Carver - 29 January 2008 at 11:08pm
Back to Top
DeTrevni View Drop Down
Moderator Group
Moderator Group
Avatar
b-YOU-ick. Was that so hard?

Joined: 19 September 2005
Location: Houston, Texas
Status: Offline
Points: 11957 		Post Options Post Options   Thanks (0) Thanks(0)   Quote DeTrevni Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 11:07pm
Hit the stop button on the treadmill when the plane is going at full tilt. Make that sucker fly. Problem solved.
Evil Elvis: "Detrevni is definally like a hillbilly hippy from hell"
Back to Top
Gatyr View Drop Down
Platinum Member
Platinum Member

Strike 1 - Begging for strikes

Joined: 06 July 2003
Location: Austin, Tx
Status: Offline
Points: 10300 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Gatyr Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 11:09pm
Originally posted by Tolgak Tolgak wrote:

You explanations are flawed.

The wheels do not generate the power, the prop/jet/rocket/fan does. The only thing you'll accomplish is making the wheels rotate twice as fast. The plane will take off a bit slower than normal, only because the wheels will be contacting the runway which will create considerable drag.


:(

I was hoping to post it.
Back to Top
carl_the_sniper View Drop Down
Platinum Member
Platinum Member
Avatar
Strike 1 - 7/29, Bad Linky

Joined: 08 April 2006
Location: Canada
Status: Offline
Points: 11259 		Post Options Post Options   Thanks (0) Thanks(0)   Quote carl_the_sniper Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 11:14pm
Originally posted by Jack Carver Jack Carver wrote:


edit: but it only moves a lot of air over a small part of the wing. The plane works because the entire wing causes lift. Your props would have to be spinning like a mofo to cause enough lift to get it in the air.


Thus my point though, that it could take off but only if the right aircraft was used.
Back to Top
choopie911 View Drop Down
Moderator Group
Moderator Group
Avatar
Commie Canuck

Joined: 01 June 2003
Location: Canada
Status: Offline
Points: 30773 		Post Options Post Options   Thanks (0) Thanks(0)   Quote choopie911 Quote  Post ReplyReply Direct Link To This Post Posted: 29 January 2008 at 11:20pm
I went over this before: yes it will.

The treadmill matches the tires, yes. No thrust is coming from the tires, it's all in the engines. Yeah the tires will spin hella fast, but it will take off regardless.
Back to Top
 Post Reply Post Reply Page  123 5>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.04
Copyright ©2001-2021 Web Wiz Ltd.

This page was generated in 2.391 seconds.