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Dallas
February 1st 08, 04:42 PM
In case you missed it, here's the segment on You Tube:

http://youtube.com/watch?v=KSBFQOfas60&feature=related

And yet, the debate continues. :- (

--
Dallas

Bertie the Bunyip[_24_]
February 1st 08, 05:38 PM
Dallas > wrote in
:

>
> In case you missed it, here's the segment on You Tube:
>
> http://youtube.com/watch?v=KSBFQOfas60&feature=related
>
> And yet, the debate continues. :- (
>

What debate?

Bertie

Robert M. Gary
February 1st 08, 05:47 PM
On Feb 1, 9:38*am, Bertie the Bunyip > wrote:
> Dallas > wrote :
>
>
>
> > In case you missed it, here's the segment on You Tube:
>
> >http://youtube.com/watch?v=KSBFQOfas60&feature=related
>
> > And yet, the debate continues. *:- (
>
> What debate?
>
> Bertie

Check out the comments no the video at youtube. People are still
arguing whether the sheet that was drug from the truck was going the
same speed as the truck due to drag of the sheet on the ground (don't
ask me, I didn't say it).

-Robert

Bertie the Bunyip[_24_]
February 1st 08, 05:56 PM
"Robert M. Gary" > wrote in
:

> On Feb 1, 9:38*am, Bertie the Bunyip > wrote:
>> Dallas > wrote
>> innews:18d6la9n21rdn.1r02js
> :
>>
>>
>>
>> > In case you missed it, here's the segment on You Tube:
>>
>> >http://youtube.com/watch?v=KSBFQOfas60&feature=related
>>
>> > And yet, the debate continues. *:- (
>>
>> What debate?
>>
>> Bertie
>
> Check out the comments no the video at youtube. People are still
> arguing whether the sheet that was drug from the truck was going the
> same speed as the truck due to drag of the sheet on the ground (don't
> ask me, I didn't say it).
>

Good grief.

Bertie

Dallas
February 1st 08, 06:27 PM
On Fri, 1 Feb 2008 17:56:47 +0000 (UTC), Bertie the Bunyip wrote:

> Good grief.

Check out the comments at the Mythbusters site.

http://mythbustersresults.com/episode97#comments

"You blew it big time. I am a pilot and I can tell you that the myth about
the airplane conveyor belt is supposed to be confirmed."

He's not a pilot, he's an idiot.

--
Dallas

B A R R Y[_2_]
February 1st 08, 06:34 PM
Dallas wrote:
> In case you missed it, here's the segment on You Tube:

Jamie got a new truck! <G>

Jim Logajan
February 1st 08, 07:03 PM
Dallas > wrote:
> On Fri, 1 Feb 2008 17:56:47 +0000 (UTC), Bertie the Bunyip wrote:
>
>> Good grief.
>
> Check out the comments at the Mythbusters site.
>
> http://mythbustersresults.com/episode97#comments
>
> "You blew it big time. I am a pilot and I can tell you that the myth
> about the airplane conveyor belt is supposed to be confirmed."
>
> He's not a pilot, he's an idiot.

Hey man - it's still a free country and there is no law that says you can't
be both an idiot and a pilot at the same time! ;-)

Bertie the Bunyip[_24_]
February 1st 08, 07:28 PM
Dallas > wrote in
:

> On Fri, 1 Feb 2008 17:56:47 +0000 (UTC), Bertie the Bunyip wrote:
>
>> Good grief.
>
> Check out the comments at the Mythbusters site.
>
> http://mythbustersresults.com/episode97#comments
>
> "You blew it big time. I am a pilot and I can tell you that the myth
> about the airplane conveyor belt is supposed to be confirmed."
>
> He's not a pilot, he's an idiot.
>

But I would believe he might fly. There are plenty of them out there.

The dreaded downwind turn, turning into the dead engine, all those myths
still have their adherents amongst current pilots.

Bertie

Dallas
February 1st 08, 08:54 PM
On Fri, 1 Feb 2008 19:28:03 +0000 (UTC), Bertie the Bunyip wrote:

> The dreaded downwind turn, turning into the dead engine, all those myths
> still have their adherents amongst current pilots.

What about agreeing to place your aircraft on top of a very large piece of
fabric, cranking up the engine and firewalling it.

Imagine calling your insurance company trying to explain how a 100 foot
strip of fabric got fouled into your prop.

--
Dallas

Bertie the Bunyip[_24_]
February 1st 08, 09:04 PM
Dallas > wrote in
:

> On Fri, 1 Feb 2008 19:28:03 +0000 (UTC), Bertie the Bunyip wrote:
>
>> The dreaded downwind turn, turning into the dead engine, all those
>> myths still have their adherents amongst current pilots.
>
> What about agreeing to place your aircraft on top of a very large
> piece of fabric, cranking up the engine and firewalling it.
>
> Imagine calling your insurance company trying to explain how a 100
> foot strip of fabric got fouled into your prop.
>

Well, it was a bit of lawn furniture, wasn't it?


Bertie

Chris W
February 1st 08, 09:26 PM
Dallas wrote:
> In case you missed it, here's the segment on You Tube:
>
> http://youtube.com/watch?v=KSBFQOfas60&feature=related
>
> And yet, the debate continues. :- (

The only debate was due to the VERY ambiguous way the scenario was
worded. In that episode, they were very careful to word in a very
unambiguous way. When you remove the ambiguity, it either becomes a
situation where it is obvious that the plane will take off, or a
situation that is physically impossible to achieve. Naturally the myth
busters choose the first scenario.


--
Chris W
KE5GIX

"Protect your digital freedom and privacy, eliminate DRM,
learn more at http://www.defectivebydesign.org/what_is_drm"

Ham Radio Repeater Database.
http://hrrdb.com

Dallas
February 1st 08, 09:26 PM
On Fri, 1 Feb 2008 21:04:25 +0000 (UTC), Bertie the Bunyip wrote:

> Well, it was a bit of lawn furniture, wasn't it?

Yeah, that's the ticket... it was an awning I was using as shade over the
airplane...
--
Dallas

Bertie the Bunyip[_24_]
February 1st 08, 09:45 PM
Dallas > wrote in
:

> On Fri, 1 Feb 2008 21:04:25 +0000 (UTC), Bertie the Bunyip wrote:
>
>> Well, it was a bit of lawn furniture, wasn't it?
>
> Yeah, that's the ticket... it was an awning I was using as shade over
> the airplane...

OK, you lost me now.

Bertie

Robert M. Gary
February 1st 08, 09:56 PM
On Feb 1, 12:54*pm, Dallas > wrote:
> On Fri, 1 Feb 2008 19:28:03 +0000 (UTC), Bertie the Bunyip wrote:
> > The dreaded downwind turn, turning into the dead engine, all those myths
> > still have their adherents amongst current pilots.
>
> What about agreeing to place your aircraft on top of a very large piece of
> fabric, cranking up the engine and firewalling it.
>
> Imagine calling your insurance company trying to explain how a 100 foot
> strip of fabric got fouled into your prop.

I'd be surprised if he had insurance on it.

-Robert

Dudley Henriques[_2_]
February 1st 08, 11:49 PM
Jim Logajan wrote:
> Dallas > wrote:
>> On Fri, 1 Feb 2008 17:56:47 +0000 (UTC), Bertie the Bunyip wrote:
>>
>>> Good grief.
>> Check out the comments at the Mythbusters site.
>>
>> http://mythbustersresults.com/episode97#comments
>>
>> "You blew it big time. I am a pilot and I can tell you that the myth
>> about the airplane conveyor belt is supposed to be confirmed."
>>
>> He's not a pilot, he's an idiot.
>
> Hey man - it's still a free country and there is no law that says you can't
> be both an idiot and a pilot at the same time! ;-)

Hell yeah! If anyone doesn't believe that, ask my wife!!
:-)

--
Dudley Henriques

Dudley Henriques[_2_]
February 1st 08, 11:51 PM
Dallas wrote:
> On Fri, 1 Feb 2008 19:28:03 +0000 (UTC), Bertie the Bunyip wrote:
>
>> The dreaded downwind turn, turning into the dead engine, all those myths
>> still have their adherents amongst current pilots.
>
> What about agreeing to place your aircraft on top of a very large piece of
> fabric, cranking up the engine and firewalling it.
>
> Imagine calling your insurance company trying to explain how a 100 foot
> strip of fabric got fouled into your prop.
>
You know, I watched that thing and this was my only thought as I watched
them set it all up.

--
Dudley Henriques

Dallas
February 2nd 08, 06:59 AM
On Fri, 01 Feb 2008 18:51:44 -0500, Dudley Henriques wrote:

> You know, I watched that thing and this was my only thought as I watched
> them set it all up.

Oh well, he was dumb enough to think the aircraft wouldn't take off so what
makes you think he'd consider anything more complicated than that?

:- )


--
Dallas

Dallas
February 2nd 08, 07:01 AM
On Fri, 1 Feb 2008 21:45:11 +0000 (UTC), Bertie the Bunyip wrote:

> OK, you lost me now.

Wow.. that's kinda neat... I befuddled a Bunyip.

--
Dallas

Bertie the Bunyip[_24_]
February 2nd 08, 09:00 AM
Dallas > wrote in
:

> On Fri, 1 Feb 2008 21:45:11 +0000 (UTC), Bertie the Bunyip wrote:
>
>> OK, you lost me now.
>
> Wow.. that's kinda neat... I befuddled a Bunyip.
>

Hey, I failed gibberish, what can I say? ;)


Bertie

PeeCeeElf
February 2nd 08, 04:03 PM
I've just posted to another forum on the subject. I think the
Mythbusters demo was completely flawed and didn't address the question
as it was originally asked. Of course the aircraft was going to fly
given the nature of their experiment.

http://tinyurl.com/yt79o5


--
PeeCeeElf
Posted at www.flight.org

Steven P. McNicoll
February 2nd 08, 04:29 PM
"PeeCeeElf" > wrote in message
...
>
> I've just posted to another forum on the subject. I think the
> Mythbusters demo was completely flawed and didn't address the question
> as it was originally asked. Of course the aircraft was going to fly
> given the nature of their experiment.
>

How was the question originally asked?

Bertie the Bunyip[_24_]
February 2nd 08, 04:41 PM
PeeCeeElf > wrote in
:

>
> I've just posted to another forum on the subject.

Well, if you;re loking for someone to agree with you then that's probably
the best thing to do.

Might I suggest alt.conpsiracy or alt.fluffy.bunnies?


Bertie

Thomas Borchert
February 2nd 08, 05:34 PM
PeeCeeElf,

> didn't address the question
> as it was originally asked
>

There is no way to ask the question without the aircraft taking off.
The only difference is in the speed of the wheels. In one variant, it
is twice that of a "stationary runway" situation, in the other it is
infinite. In both cases, nothing keeps the aircraft from flying.

Einstein had a hard time convincing people, too.

--
Thomas Borchert (EDDH)

Jim Logajan
February 2nd 08, 07:43 PM
"Steven P. McNicoll" > wrote:
> How was the question originally asked?

Will be interesting to see "PeeCeeElf" says the "original" question was. I
believe it was this variant though [1]:

"A plane is standing on a runway that can move (some sort of band
conveyer). The plane moves in one direction, while the conveyer moves in
the opposite direction. This conveyer has a control system that tracks the
plane speed and tunes the speed of the conveyer to be exactly the same (but
in the opposite direction). Can the plane take off?"

But some versions use something like this:

[Blah blah] "speed of wheels" [blah blah].

I suspect the debate in those version is over the meaning of "speed of
wheels" which arguably can have two commonly used meanings:

(1) Translational motion of the center axle of the wheel relative to the
ground.

(2) Rotational motion of the outer rim of the wheel relative to the wheel's
axle.

Of course (1) appears synonomous with saying "Can a plane take off if the
conveyor belt moves at whatever speed it takes to keep the wheel's axle
stationary relative to the ground?" or more briefly: "Can a plane take off
if it is held stationary on the ground?"

The problem with at least one variant that includes "speed of wheels" was
covered by Cecil Adams TWO YEARS AGO:

"However, some versions put matters this way: "The conveyer belt is
designed to exactly match the speed of the wheels at any given time, moving
in the opposite direction of rotation." This language leads to a paradox:
If the plane moves forward at 5 MPH, then its wheels will do likewise, and
the treadmill will go 5 MPH backward. But if the treadmill is going 5 MPH
backward, then the wheels are really turning 10 MPH forward. But if the
wheels are going 10 MPH forward . . . Soon the foolish have persuaded
themselves that the treadmill must operate at infinite speed. Nonsense.
The question thus stated asks the impossible -- simply put, that A = A + 5
-- and so cannot be framed in this way. Everything clear now? Maybe not.
But believe this: The plane takes off." [1]

[1] http://www.straightdope.com/columns/060203.html

PeeCeeElf[_2_]
February 3rd 08, 11:15 PM
Jim Logajan Wrote:
> "Steven P. McNicoll" > wrote:
> > How was the question originally asked?
>
> Will be interesting to see "PeeCeeElf" says the "original" question
> was. I believe it was this variant though

Something like that Jim. The way I see it is that the question causes
more confusion than the inevitable outcome. Any way you look at it, the
aircraft will fly. You could turn that treadmill over at virtually any
speed and a little ultralight would probably blast off.

I did have problems with the way the question was worded (originally)
but I've cleared it up in my feeble mind. I'm Australian, and ya gotta
talk a little s-l-o-w-e-r for us cobbers to understand what ya sayin'.
It must be all that time I've spent flying inverted.. all the blood has
rushed to my head :)


--
PeeCeeElf
Posted at www.flight.org

Some Other Guy
February 4th 08, 01:14 AM
Dallas wrote:
> In case you missed it, here's the segment on You Tube:
>
> http://youtube.com/watch?v=KSBFQOfas60&feature=related
>
> And yet, the debate continues. :- (

Dear God, let it end already.

It's like that friend of mine who was convinced that if an airplane
does a U-turn against a 40-knot headwind, it will stall and crash.

As if wings are somehow aware of the planet beneath them.
It's the same damn thing.

NEWS
February 4th 08, 10:26 PM
"PeeCeeElf" > wrote in message
...
>
> Jim Logajan Wrote:
>> "Steven P. McNicoll" > wrote:
>> > How was the question originally asked?
>>
>> Will be interesting to see "PeeCeeElf" says the "original" question
>> was. I believe it was this variant though
>
> Something like that Jim. The way I see it is that the question causes
> more confusion than the inevitable outcome. Any way you look at it, the
> aircraft will fly. You could turn that treadmill over at virtually any
> speed and a little ultralight would probably blast off.
>
> I did have problems with the way the question was worded (originally)
> but I've cleared it up in my feeble mind. I'm Australian, and ya gotta
> talk a little s-l-o-w-e-r for us cobbers to understand what ya sayin'.
> It must be all that time I've spent flying inverted.. all the blood has
> rushed to my head :)
>

This whole thing is done and over the Mythbusters busted the myth that it
wouldn't take off, can we PLEASE let it die!

Edward A. Falk
February 5th 08, 12:00 AM
To solve this puzzle, you need to ask how the control system works.

Method #1: A device attached to the vehicle monitors the speed of the
wheels and transmits this to the conveyor belt's control system which
runs the belt in the opposite direction at the same speed.

Method #2: Some sort of position-detecting system observes the vehicle's
position on the belt, and feeds back to a servo system that increases
the belt's backwards speed if the vehicle starts making forward progress,
or decreases it if the vehicle starts sliding backwards.

(Someone want to propose a different control system?)



Both systems are actually equivalent in their effects on automobiles
and airplanes.

An automobile is held in position no matter what the driver attempts
to do.

With airplanes, the situation is different. Because the plane has
free-wheeling wheels, and doesn't depend on pushing against the belt in
order to move forward, it begins to make progress.

At this point, the belt -- which is a perfect conveyor belt -- instantly
speeds up to infinite speed. The airplane's wheels -- which are perfect
wheels -- likewise instantly spin up to infinite speed. Since the wheels
are perfect and have no friction, the airplane is not affected and takes
off anyway.

If you don't assume perfect abstractions, then the answer depends on
what happens first: Either a) the belt reaches its upper speed limit
and the plane takes off, b) the plane's bearing seize and the plane is
flung backwards off the belt, or c) the breeze caused by friction between
the belt and the atmosphere is sufficient for the plane to take off
before a) or b) happens.

--
-Ed Falk,
http://thespamdiaries.blogspot.com/

Edward A. Falk
February 5th 08, 12:06 AM
In article >,
NEWS <theducksmail"AT"yahoo.com> wrote:
>
>This whole thing is done and over the Mythbusters busted the myth that it
>wouldn't take off, can we PLEASE let it die!

Actually, PeeCeeElf was correct; they didn't do the experiment right.
The puzzle assumes some sort of feedback mechanism to keep the belt
moving exactly at the opposite speed as the airplane. The mythbusters
guys didn't do that.

However, Cecil Adams is also right; it's not possible. Doing the test
right assumes that you believe in A = A + 5.
--
-Ed Falk,
http://thespamdiaries.blogspot.com/

Jim Logajan
February 5th 08, 02:20 AM
(Edward A. Falk) wrote:
> To solve this puzzle, you need to ask how the control system works.

No. You need to first write out the "puzzle" precisely as you first found
it.

Judah
February 6th 08, 07:34 AM
(Edward A. Falk) wrote in news:fo899k$kre$1
@blue.rahul.net:

> In article >,
> NEWS <theducksmail"AT"yahoo.com> wrote:
>>
>>This whole thing is done and over the Mythbusters busted the myth that it
>>wouldn't take off, can we PLEASE let it die!
>
> Actually, PeeCeeElf was correct; they didn't do the experiment right.
> The puzzle assumes some sort of feedback mechanism to keep the belt
> moving exactly at the opposite speed as the airplane. The mythbusters
> guys didn't do that.
>
> However, Cecil Adams is also right; it's not possible. Doing the test
> right assumes that you believe in A = A + 5.

The puzzle also assumes that the wheels are what drive the plane on the
ground. The speed that the wheels rotate on the conveyor belt is irrelevant
relative to the motion of the plane caused by the thrust of the engine on the
ground (or conveyor).

Judah
February 6th 08, 07:36 AM
(Edward A. Falk) wrote in news:fo88v9$h38$2
@blue.rahul.net:

> At this point, the belt -- which is a perfect conveyor belt -- instantly
> speeds up to infinite speed. The airplane's wheels -- which are perfect
> wheels -- likewise instantly spin up to infinite speed. Since the wheels
> are perfect and have no friction, the airplane is not affected and takes
> off anyway.

In order for the friction to really be 0, the plane must be in a vaccuum.

However, in a vaccuum, there would be no air to travel past the wings to
generate lift, and therefore it would not fly.

Thomas Borchert
February 6th 08, 08:43 AM
Judah,

> However, in a vaccuum, there would be no air to travel past the wings to
> generate lift, and therefore it would not fly.
>

Ah, but what if it is ground vacuum?

--
Thomas Borchert (EDDH)

Judah
February 6th 08, 12:59 PM
Thomas Borchert > wrote in
:

> Judah,
>
>> However, in a vaccuum, there would be no air to travel past the wings to
>> generate lift, and therefore it would not fly.
>>
>
> Ah, but what if it is ground vacuum?
>

You mean like a hoover?

Then it will get sucked in regardless of the wheels or conveyor...

February 6th 08, 05:19 PM
On Feb 4, 5:00*pm, (Edward A. Falk) wrote:
> To solve this puzzle, you need to ask how the control system works.
>
> Method #1: *A device attached to the vehicle monitors the speed of the
> wheels and transmits this to the conveyor belt's control system which
> runs the belt in the opposite direction at the same speed.
>
> Method #2: *Some sort of position-detecting system observes the vehicle's
> position on the belt, and feeds back to a servo system that increases
> the belt's backwards speed if the vehicle starts making forward progress,
> or decreases it if the vehicle starts sliding backwards.
>
> (Someone want to propose a different control system?)
>
> Both systems are actually equivalent in their effects on automobiles
> and airplanes.
>
> An automobile is held in position no matter what the driver attempts
> to do.
>
> With airplanes, the situation is different. *Because the plane has
> free-wheeling wheels, and doesn't depend on pushing against the belt in
> order to move forward, it begins to make progress.
>
> At this point, the belt -- which is a perfect conveyor belt -- instantly
> speeds up to infinite speed. *The airplane's wheels -- which are perfect
> wheels -- likewise instantly spin up to infinite speed. *Since the wheels
> are perfect and have no friction, the airplane is not affected and takes
> off anyway.
>
> If you don't assume perfect abstractions, then the answer depends on
> what happens first: *Either a) the belt reaches its upper speed limit
> and the plane takes off, b) the plane's bearing seize and the plane is
> flung backwards off the belt, or c) the breeze caused by friction between
> the belt and the atmosphere is sufficient for the plane to take off
> before a) or b) happens.
>
> --
> * * * * -Ed Falk,
> * * * *http://thespamdiaries.blogspot.com/

Well, if you are going to start inserting idealized and impossible
conditions, then lets say that the wheels are also ideal and generate
no friction. In that case, the plane will still take off because the
wheels impart no force whatsoever on the airplane...

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