Airplane on Conveyor Belt Mythbusters 12/12

[Scab]

OK. Watch this SLIGHTLY NWS vid...

Bwaaaaaaaaaaaaaaaaa!

"****** and Strife."

Yep, that about sums it up.

 

[jocko87]

This has got to be the most amusing and ridiculous thread ever ! LOL...now I know why there are so few pilots around. There are 4 forces involved in flight...Thrust, Drag, Lift , and weight. Regardless of Thrust, Drag, or Weight ,without adequate air flow over a wing to create LIFT, that wing WILL NOT FLY...Ground speed means NOTHING. AIR SPEED is the determing factor to generate lift. Based on the assumption that a treadmill will spin at the same rate as the rolling landing gear, the plane remains motionless, both in ground speed and air speed(save for the little prop wash, which is not "clean" air flow over the entire wing). No air speed, no fly.
For the mathmatically challenged... L=CLV2p/2S

L = Lift

CL=Coeffieicent of lift

V = Velocity (in ft per sec)

p=Air Density

S = Wing surface area (Sq. ft.)

Jay

'04 FJR 1300

Private Pilot , Single Engine Land, PPC Land

Simply amazing how many pilots don't understand the physics of flight.

Ooooooo....here is a much better way to look at it.
This helps clear it up (I think so anyway).

This IS essentially what the experiment is describing. Weight on the wheels doesn't matter, only that they are spinning at on the treadmill--same as an airplane. So if the wheels are touching the treadmill, will the helicopter be able to gain altitude? Of course it will.

Now rotate that picture 90 degrees to the left, treadmill on the bottom. Will the helicopter move to the left? No reason why it wouldn't. No reason why an airplane wouldn't do the same thing, moving along at a rate equal to thrust produced by the engines. It the airplane will move, it will take off...no question.

Jay, The part of your equation that is wrong is that drag (wheels on the treadmill??) is not the opposing force of lift (airflow over the wing)

Lift opposes gravity, thrust opposes drag. Wheels on the treadmill is not drag, gear down in flight is a good example of drag. Drag is an effect on airflow, and the treadmill does not effect airflow.

If you believe the treadmill can match speed with the aircraft wheels, you must also believe in perpetual motion right? The only real question here is if the wheels would explode before the plane lifted off due to the crazy speed-multiplication trying to match each other.

 

[krashdragon]

I fly r/c, both airplanes and Helis. I'm still trying to figure out a way to transport some rc toys on my Feejer

Enclosed trailer?

That would take the fun out of the ride, I may as well throw them in the back of my SUV like I do now

How about a nice heavy kite string?

You'd have forward motion and lift.... except at red lights! :rofl:

Mary

 

[slapnpop]

Moved to NEPRT.

Anyone continuing in this thread is either stupid for not understand the right answer.. or stupid for arguing with those too stupid to understand the right answer.

Bicker amongst yourselves now to figure out which is which... :lol:

Gunny, you make me laugh beverage all over my computer screen!

 

[Scythian]

Moved to NEPRT.
Anyone continuing in this thread is either stupid for not understand the right answer.. or stupid for arguing with those too stupid to understand the right answer.

Bicker amongst yourselves now to figure out which is which... :lol:

Gunny, you make me laugh beverage all over my computer screen!

Gunny on the NERPT. Please let it not repeat....

However, the AF pilots in the aircraft program I work on did get a good laugh out of the responses, 'specially the responses from the pilots here!

People are going to feel dumb once they figure this one out. Almost as dumb as I feel for trying to 'splain it on them....

 

[SouthernCruizer]

Moved to NEPRT.
Anyone continuing in this thread is either stupid for not understand the right answer.. or stupid for arguing with those too stupid to understand the right answer.

Bicker amongst yourselves now to figure out which is which... :lol:

Gunny, you make me laugh beverage all over my computer screen!

Gunny on the NERPT. Please let it not repeat....

However, the AF pilots in the aircraft program I work on did get a good laugh out of the responses, 'specially the responses from the pilots here!

People are going to feel dumb once they figure this one out. Almost as dumb as I feel for trying to 'splain it on them....

*******************

Talk on the internet is cheap

The gov't, and 20+ years and thousands of hours of real flight time in various aircraft, not theoretical flight , say that this pilot understands the principals of flight

But believe what you will..after all, its Christmas season, and as YOU know, Santa Clause is a real dude too! LOL

Jay

'04 FJR 1300

 

[Scythian]

The gov't, and 20+ years and thousands of hours of real flight time in various aircraft, not theoretical flight , say that this pilot understands the principals of flight

OoooOOOOOOooooh..... :lol:

That's unfortunate.

 

[Bearly Flying]

No offense Southern, But I think I'll pass on riding with you in a Plane. Thanks anyways...

 

[Bearly Flying]

Airspeed....We don't need no stinking Airspeed....

 

[Toecutter]

The funny part is, that by the time the episode actually airs, this will be a distant memory and we'll be arguing about something completely different....

 

[germany]

You are in a car traveling 30 mph on a stretch of flat road. There are three checkpoints marked on the road: start, 0.5 mile and 1.0 mile. When you cross the start, you are still traveling 30mph and maintain that speed until you cross the 0.5 mile mark. How fast do you have to go for the remaining 0.5 mile to obtain an average 60mph for the entire 1.0mile stretch of road?

 

[ponyfool]

You are in a car traveling 30 mph on a stretch of flat road. There are three checkpoints marked on the road: start, 0.5 mile and 1.0 mile. When you cross the start, you are still traveling 30mph and maintain that speed until you cross the 0.5 mile mark. How fast do you have to go for the remaining 0.5 mile to obtain an average 60mph for the entire 1.0mile stretch of road?

Using simple algebra, the answer would be 90. But, that would be incorrect.

In order to average 60mph across that 1 mile stretch of road, your total driving time would have to be one minute. However, by going 30 mph for the first half mile, you've already used up that minute, thus, it is impossible to average 60 mph over the entire mile.*

*Unless you were in a modified DeLorean and went 88mph

 

[JimLor]

Yeah, let's move anything that actually involves the use of one's brain and actually active thought to the NERPT side of the house and while we're at it let's call folks stupid if they discuss something you don't want to discuss. Gee, I can't wait for the next riviting thread discussing air filted mediums - paper, metal...

And by the way, you don't need to understand the physics of *** to dive in and do a credible job. And one, basically anyone, can actually fly without obtaining an aeronautical Phd - I have a pilots license and I was a History major. And for those who call folks here stupid for expressing what they think, open as wide as you can and friggin' bite me; then open up and do it again!

I'm sure I'll be corrected if I'm wrong, but I don't think the rules here state that you must open and comment in every single thread posted. If you don't like the subject, comments, etc, then don't read 'em. It's moved now, but I think it started in the off-topic part of the forum, if not for off-topic discussions then what the hell is that for?

Enjoy your Friday.

 

[ponyfool]

SouthernCruizer, like Xviper and Rondo, are dead on when it comes to the principal of flight. We all agree on that. No airflow means no flight. They just can't get passed the fact that the thrust is independent of the contact with the treadmill and they somehow think the treadmill will act as some kind of brake holding the plane in place.

Go look at the skateboard post above. There is no ability for the treadmill to negate the forward movement.

I wouldn't have a problem flying with any of them. I'd have a problem while the plane is on the ground!

 

[GunMD]

Gunny, you make me laugh beverage all over my computer screen!

Glad I could help.

Now get back to your trailer!!

 

[BobG]

So you put a plane in a long building point it west on the equator. Eliminate external wind, will it fly forward or backwards in relation to a point in space? No one ever said the atmosphere can't move in relation to the treadmill. The earth is still the conveyor belt.

Even the treadmill in my house creates air flow. Is that due to its gravity or motion?

The whole point of this ludicrous question is what creates lift. I say it is all the passengers in the plane thinking happy thoughts and snorting fairy dust.

Bob

 

[Fred W]

The funny part is, that by the time the episode actually airs, this will be a distant memory and we'll be arguing about something completely different....

One would certainly hope so...

 

[Groo]

Only one problem with that scenario...in the case of a plane, the engine and prop are ON the treadmill, not off in front on solid ground like someone pulling with a rope.

Uh, no. Force is force, and this system is not-relativistic. Having a jet engine or prop ON the treadmill or off makes no difference whatsoever.

I'm under impression that this is a powered treadmill that can be made to move at the same max speed as the plane can produce forward thrust. If it were a free wheeling treadmill then the plane would indeed just take off as usual.

The tires can spin at an infinite speed... it doesn't matter. Like ponyfool showed... if there is a force applied to the plane, it will move forward. The wheels are not part of the driving force, they are just spinning because they are in contact with the treadmill. Even a powered treadmill won't make any difference in keeping the plane from moving, assuming the engines are providing thrust.

 

[Toecutter]

This topic needs a poll.

Or a hole....

 

[twowheelnut]

Yeah, let's move anything that actually involves the use of one's brain and actually active thought to the NERPT side of the house and while we're at it let's call folks stupid if they discuss something you don't want to discuss. Gee, I can't wait for the next riviting thread discussing air filted mediums - paper, metal...
And by the way, you don't need to understand the physics of *** to dive in and do a credible job. And one, basically anyone, can actually fly without obtaining an aeronautical Phd - I have a pilots license and I was a History major. And for those who call folks here stupid for expressing what they think, open as wide as you can and friggin' bite me; then open up and do it again!

I'm sure I'll be corrected if I'm wrong, but I don't think the rules here state that you must open and comment in every single thread posted. If you don't like the subject, comments, etc, then don't read 'em. It's moved now, but I think it started in the off-topic part of the forum, if not for off-topic discussions then what the hell is that for?

Enjoy your Friday.

I don't care who you are, that right there is some funny ****! :rofl:

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Did you know that the average person uses approximately fifty-seven sheets of toilet paper each day? Judging by the body of this particular thread, I'd have to say that it is a true statement.