Can a Plane on a Treadmill Take Off?

Saw this question on "The Straight Dope" and I thought it was amusing.

http://www.straightdope.com/columns/060203.html

The question goes like this:

"An airplane on a runway sits on a conveyer belt that moves in the
opposite direction at exactly the speed that the airplane is moving
forward. Does the airplane take off?" (Assuming the tires hold out, of
course.)

Cecil Adams (world's smartest human being) says that it will take off
normally.

In article .com,
"cjcampbell" wrote:

Saw this question on "The Straight Dope" and I thought it was amusing.

http://www.straightdope.com/columns/060203.html

The question goes like this:

"An airplane on a runway sits on a conveyer belt that moves in the
opposite direction at exactly the speed that the airplane is moving
forward. Does the airplane take off?" (Assuming the tires hold out, of
course.)

Cecil Adams (world's smartest human being) says that it will take off
normally.

He's right.

rg

Ok, so all of us do not comment on his site, or well maybe that would
be better, does this guy really not have any sense to know that the
ground speed is completely irreleveant to aerodynamics(thinking of the
threads about 152s with 0 or negative ground speed)? whatever....
airspeed is zero, no lift, no fly.
Jester

In a previous article, "jesse" said:
Ok, so all of us do not comment on his site, or well maybe that would
be better, does this guy really not have any sense to know that the
ground speed is completely irreleveant to aerodynamics(thinking of the
threads about 152s with 0 or negative ground speed)? whatever....
airspeed is zero, no lift, no fly.

Hopefully the people commenting on his site aren't as stupid as you.


--
Paul Tomblin http://xcski.com/blogs/pt/
#define sizeof(x) ((int)rand()*1024)

Actually, this has a real world parallel. A Seaplane taking off (or
landing) on a river. There are three speeds here. The speed relative to
the conveyer belt (river), the speed relative to the non-moving ground
(riverbank), and the airspeed. Put in some wind and you can get some
complicated scenarios.

"cjcampbell" wrote:
Saw this question on "The Straight Dope" and I thought it was amusing.

http://www.straightdope.com/columns/060203.html

Seems Cecil Adams is compounding the confusion by having the page's title
begin:

"An airplane taxies in one direction...."

So is the plane attempting to taxi or take off? The page's title says one
thing, the person posing the question is stating another. The hypothetical
pilot of the taxing plane would presumably not let the the airspeed go to
takeoff speed, while the pilot of the plane taking off would want to
accelerate to rotation speed. So on that basis alone, we can say a taxing
plane isn't going to take off!

;-)

when you walk on a treadmill, do you have any significant
airspeed(minus wind and fans)? you are moving forward relative to the
treadmill belt only, your airspeed is zero, sure your legs are moving
at say three miles per hour, and the treadmill belt is moving three
miles per hour the opposite way, but without airspeed you have no
lift(assuming your arms were airfoils). its not that complicated
people. the thrust of the airplane is only used in most cases, to
provide a movement of air over the wings to cause lift. if the supposed
airplane is stationary to the air, regardless how much thrust is being
used to "keep up" with the treadmill, no lift will be created, try it
with an rc plane on a real treadmill if you dont believe me. Im not
calling anyone stupid, but didnt everybody learn in PP ground school
that ground speed has nothing to do with airspeed and the associated
lift? thats one of the first things, the most basic of things that i
was taught. im done with this topic. enjoy, let the roasting begin!
Jester
PP-ASEL
A&P

What is keeping the airplane's speed up with the conveyor belt? The
propeller. Said propeller moves air. Air causes lift. The problem is
more complicated than it seems to be at first read.

"Doug" wrote in message
oups.com...
What is keeping the airplane's speed up with the conveyor belt? The
propeller. Said propeller moves air. Air causes lift. The problem is
more complicated than it seems to be at first read.

Another way to say it; it had better be a long conveyer belt, cause the prop
is pulling the plane forward, without caring how fast the wheels are going.
That will make the necessary airspeed to lift off.
--
Jim in NC

experiment, go run with a kite(in a no wind situation) untill it flies,
measure the speed youre running. get on a teadmill and run that speed
that it took to make the kite fly. does the kite fly when youre on the
treadmill? no... same thing as the airplane on the conveyor belt. i
know i said i was done but i cant keep my hand out of this.
jester