Moparts

Planes take off , off trailer

Posted By: bigdad

Planes take off , off trailer - 07/09/20 08:45 PM

And, lets go again

[Linked Image]
Posted By: FrankenScamp

Re: Planes take off , off trailer - 07/09/20 08:51 PM

laugh2 laugh2 laugh2

popcorn
Posted By: FM3AAR

Re: Planes take off , off trailer - 07/09/20 08:59 PM

Guy with the camera was pretty brave! eek
Posted By: Mr PotatoHead

Re: Planes take off , off trailer - 07/09/20 09:01 PM

Dosent take a rocket scientist to know how they commonly get water/only planes airborn where there is no water at times, notice it was a runway it took off from.
Posted By: hooziewhatsit

Re: Planes take off , off trailer - 07/09/20 09:33 PM

laugh2

Of course a plane can take off from a treadmill. scope

The original question was flawed in that it made the assumption that the treadmill could hold the plane and prevent forward motion.

Put a wheelbarrow on a treadmill and observe that no matter how fast you make the treadmill go, you can still move the wheelbarrow forward and back just fine => a plane can take off from a treadmill too hammer
Posted By: John Brown

Re: Planes take off , off trailer - 07/09/20 09:35 PM

Take off speed is likely less than 50 mph, so not a great risk involved for the tow truck.
Posted By: Mr PotatoHead

Re: Planes take off , off trailer - 07/09/20 09:37 PM

I think the sunrise confuses some here.
Posted By: Mastershake340

Re: Planes take off , off trailer - 07/09/20 09:38 PM

I’ve seen an air show act where they takeoff and then land a Piper Cub on a platform installed on the roof of a van while the van drives down a runway.
Posted By: Pacnorthcuda

Re: Planes take off , off trailer - 07/09/20 09:48 PM

Originally Posted by hooziewhatsit
laugh2

Of course a plane can take off from a treadmill. scope

The original question was flawed in that it made the assumption that the treadmill could hold the plane and prevent forward motion.

Put a wheelbarrow on a treadmill and observe that no matter how fast you make the treadmill go, you can still move the wheelbarrow forward and back just fine => a plane can take off from a treadmill too hammer


A planes ability to take off is based on AIRSPEED. Air flowing over the wing creates LIFT. The airspeed can be from the planes forward motion, of from a headwind, or both, but it needs airspeed. Period.
Posted By: Ramrod39

Re: Planes take off , off trailer - 07/09/20 09:54 PM

Originally Posted by Pacnorthcuda


A planes ability to take off is based on AIRSPEED. Air flowing over the wing creates LIFT. The airspeed can be from the planes forward motion, of from a headwind, or both, but it needs airspeed. Period.


Yep. If the air is move over and under the wings at sufficient speed the plane can fly even if the plane is stationary.
Posted By: Mr PotatoHead

Re: Planes take off , off trailer - 07/09/20 09:54 PM

Practice the basics at home.

Attached picture FMOOR1VI7RGJ4W3.LARGE.jpg
Posted By: hooziewhatsit

Re: Planes take off , off trailer - 07/09/20 10:06 PM

Originally Posted by Pacnorthcuda
Originally Posted by hooziewhatsit
laugh2

Of course a plane can take off from a treadmill. scope

The original question was flawed in that it made the assumption that the treadmill could hold the plane and prevent forward motion.

Put a wheelbarrow on a treadmill and observe that no matter how fast you make the treadmill go, you can still move the wheelbarrow forward and back just fine => a plane can take off from a treadmill too hammer


A planes ability to take off is based on AIRSPEED. Air flowing over the wing creates LIFT. The airspeed can be from the planes forward motion, of from a headwind, or both, but it needs airspeed. Period.


Correct! And a treadmill is incapable of preventing a plane from making forward motion or the resulting airspeed, so it then takes off up
Posted By: Sniper

Re: Planes take off , off trailer - 07/09/20 10:41 PM

But it doesn't "take off" from the treadmill, it will roll off it and keep rolling till it gets enough airspeed but it doesn't get airborne off the treadmill, unless your treadmill is runway length.
Posted By: poorboy

Re: Planes take off , off trailer - 07/10/20 01:02 AM

I'll bet landing is more impressive then taking off. Exactly how do they land water planes at an airport? Gene
Posted By: Cab_Burge

Re: Planes take off , off trailer - 07/10/20 02:02 AM

Originally Posted by poorboy
I'll bet landing is more impressive then taking off. Exactly how do they land water planes at an airport? Gene
Most float planes have retractable wheels in the floats and retractable rudders so they can lift the rudder to use the wheels to land on hard surfaces and lower the rudders and raise the wheels to land on water up
Same thing on the other type of planes,( amphibieans (SP?) that where designed primarily to land and take off on water, they have wheels in the floats to land and or taxi on hard surfaces when needed scope
Posted By: ChryCoGuy

Re: Planes take off , off trailer - 07/10/20 12:33 PM

Cool video, thanks for posting it as I've never seen that done before. The trailer looks purpose-built?
Posted By: Mastershake340

Re: Planes take off , off trailer - 07/10/20 12:41 PM

It’s probably a company that does float conversions on light planes. The plane landed at the airport with conventional landing gear, the company removed that, installed floats, and had built that trailer as a way to launch the plane after the conversion was completed.
Otherwise they would need to disassemble the plane and then put it back together at a waterway, a much more complicated procedure.
Posted By: wingman

Re: Planes take off , off trailer - 07/10/20 12:51 PM

But was the trailer on a treadmill?
Posted By: roadrunninMark

Re: Planes take off , off trailer - 07/10/20 02:11 PM

An airplane will not take off on a treadmill if it is maintaining its position. I will relate this to someone running on a treadmill for comparison sake, since almost everyone has been on a treadmill. If you stand on a treadmill, it will move you backwards. You have to run/walk to at exact the same speed in the opposite direction to maintain your position. If you do this, your upper body is in a stationary position. You do not gain nor lose ground. Step off the treadmill while you are maintaining this speed and you instantly go forward. Stop running/walking and you instantly go backward. There is no airflow around you, since you are in a stationary position. Remember when you were young and stuck your hand out the window of a moving vehicle? You made a “wing shape” with your hand? If you tilted your hand up, it would lift your hand/arm. Opposite if you tilted your hand down. Try this next time you are on a treadmill, no airflow over or under your hand. Without airflow, a plane will not fly.

If you think because the propellor is turning, creating airflow to fly, then just look at the above video. Why would the plane need a truck then to pull it down the runway before it would take off from the platform? Think of the platform being a treadmill and the floats being the legs. It is maintaining its position on the platform, no forward nor backward movement. Even with the propellor turning, the plane still needed a certain speed forward before it reached a speed it could takeoff.
Posted By: hooziewhatsit

Re: Planes take off , off trailer - 07/10/20 03:06 PM

Originally Posted by roadrunninMark
An airplane will not take off on a treadmill if it is maintaining its position. I will relate this to someone running on a treadmill for comparison sake, since almost everyone has been on a treadmill. If you stand on a treadmill, it will move you backwards. You have to run/walk to at exact the same speed in the opposite direction to maintain your position. If you do this, your upper body is in a stationary position. You do not gain nor lose ground. Step off the treadmill while you are maintaining this speed and you instantly go forward. Stop running/walking and you instantly go backward. There is no airflow around you, since you are in a stationary position. Remember when you were young and stuck your hand out the window of a moving vehicle? You made a “wing shape” with your hand? If you tilted your hand up, it would lift your hand/arm. Opposite if you tilted your hand down. Try this next time you are on a treadmill, no airflow over or under your hand. Without airflow, a plane will not fly.

If you think because the propellor is turning, creating airflow to fly, then just look at the above video. Why would the plane need a truck then to pull it down the runway before it would take off from the platform? Think of the platform being a treadmill and the floats being the legs. It is maintaining its position on the platform, no forward nor backward movement. Even with the propellor turning, the plane still needed a certain speed forward before it reached a speed it could takeoff.


Not quite. In your treadmill example, the forward motion is coming from the person running pushing back on the treadmill.

Go back up and look at my wheelbarrow on a treadmill example. It doesn't matter how fast the treadmill is going; you'll still be able to push the wheelbarrow forward on the moving treadmill. The treadmill is incapable of holding it back. Hence, the propeller creates forward motion and airspeed, and it takes off.
Posted By: Mastershake340

Re: Planes take off , off trailer - 07/10/20 04:19 PM

In this case the plane isn't much different than a glider. A glider gets towed either by a powered aircraft or a winch/catapult type mechanism on the ground, and when the airflow over the wings is fast enough to create adequate lift, the glider flies. Or maybe better to compare to a plane getting catapulted off an aircraft carrier, where the catapult accelerates the plane to a speed where the wings develops lift, and then the thrust of the engines takes over to keep the plane flying at a speed required to maintain the lift.
If you put an airplane with the engine not running on a platform and accelerated the platform fast enough, the plane would start to fly after developing lift, and the plane would glide back down to the ground, or stall and crash into the ground depending on circumstances and how fast the pilot could react on the controls etc.
I thought the old plane on a treadmill theory had got beaten to death years ago, even Mythbusters did an episode on that. catfight
Posted By: John_Kunkel

Re: Planes take off , off trailer - 07/10/20 05:39 PM

Taking off from a moving vehicle is fairly easy, some STOL aircraft can get airborne in a stiff wind..... landing OTOH...............

https://www.youtube.com/watch?v=a8Fx_ir6McI
Posted By: Andrewh

Re: Planes take off , off trailer - 07/10/20 07:44 PM

https://www.youtube.com/watch?v=YORCk1BN7QY
Posted By: roadrunninMark

Re: Planes take off , off trailer - 07/10/20 10:46 PM

Sorry, but no Hoosie. The treadmill is causing you to go backwards. Therefore, you have airflow coming from behind you if you are losing ground. You are moving forward against the belt, yes, but not the relative wind. You will not takeoff, you will not fly, and you will not collect 200 bux (you will not pass go!) LOL

The only way you can takeoff on a treadmill is if you have a very loooooooooooooooooong treadmill and you are actually moving forward on it. AND the problem with this is that the engine will have to spin even faster to offset the original speed of the treadmill. Now if the treadmill is running in reverse, you will need less power, just like the truck pulling that float plane!
Posted By: wingman

Re: Planes take off , off trailer - 07/10/20 11:06 PM

Wow. I can't believe we are having this conversation again! grin

I think some car guys have trouble grasping the concept because they are so used to thinking about wheels pushing against the pavement.

In a plane the engine is pushing against the air, not the ground. So a conveyor belt has no effect other than to make the landing gear wheels spin a little faster. No effect.
Posted By: hooziewhatsit

Re: Planes take off , off trailer - 07/10/20 11:11 PM

Nope.

Stand on the ground, holding a wheelbarrow, and put the front wheel on a treadmill. Speed up the treadmill, and observe how the wheel spins at the same speed as the treadmill, but the wheelbarrow stays in one place.

Then see that if you push the wheelbarrow forward (on the moving treadmill), it moves forward regardless of how fast the treadmill is going. Heck, make the treadmill go in reverse, and observe how you can still push the wheelbarrow forward and back.

The original question is flawed in assuming the treadmill can hold the plane back. It can't.

HOWEVER, if the wheels of the plane were driven by the engine to be the same speed as the treadmill, then yes, it would never have any forward motion or airspeed, and never take off. But I've never seen a plane with powered wheels.
Posted By: hooziewhatsit

Re: Planes take off , off trailer - 07/10/20 11:12 PM

Originally Posted by wingman
Wow. I can't believe we are having this conversation again! grin

I think some car guys have trouble grasping the concept because they are so used to thinking about wheels pushing against the pavement.

In a plane the engine is pushing against the air, not the ground. So a conveyor belt has no effect other than to make the landing gear wheels spin a little faster. No effect.


up
Posted By: hudsonhornet7x

Re: Planes take off , off trailer - 07/11/20 12:23 AM

Here is a nice stol competition, who needs a treadmill, or heck even a runway for that matter?! https://www.youtube.com/watch?v=hPakbghLe38
Posted By: Ramrod39

Re: Planes take off , off trailer - 07/11/20 01:09 AM

This thread was fun the first time... grin
Posted By: roadrunninMark

Re: Planes take off , off trailer - 07/11/20 01:20 AM

Hoosie, your example is flawed. If someone stands on the ground holding the handles of the wheelbarrow, of course the wheel will speed up or slow down with the speed of the treadmill, but it is only the wheel. The person is acting as an anchor. Again, the body of the wheelbarrow is not moving forward or reverse. Also, how does this even relate to an airplane if it was on the treadmill? Is there a wheel (tail or nose wheel, doesn't matter which) that will not be on the treadmill? If this is the case, again, the wheels will spin but the airplane will have no forward momentum, as the person. Therefore, no airflow over the wings of the relative wind (only the wind blown by the propeller, which is no where near enough airflow).
Posted By: Andrewh

Re: Planes take off , off trailer - 07/11/20 03:17 AM

actually your example is flawed.
the airplane does not depend on the wheel speed for its speed.
the issue is the drag on the wheels is not enough to slow the plane down against the engine.

IF the plane wheels brakes were on, then it would slow the plane down against the engine.
but freewheeling doesn't prevent the plane from moving faster than the treadmill can pull it backwards by the wheels.
Posted By: hooziewhatsit

Re: Planes take off , off trailer - 07/11/20 04:54 AM

Andrew is correct.

Instead of hanging on to the wheelbarrow, put an engine with a propeller in it. And assume it balances on one wheel. It's an analogy, deal with it laugh2

The propeller will provide the forward motion, just like when you push it by hand.
Posted By: roadrunninMark

Re: Planes take off , off trailer - 07/11/20 04:14 PM

I know the aircraft doesn't depend on wheel speed to be able to takeoff,and I said that earlier, it depends upon the relative wind moving, mainly under the wing surface. I was referencing Hoosie's statement of one holding the end of the wheelbarrow with the treadmill rotating the wheel.

Now in his new example, he is putting a propeller and engine on the wheelbarrow. On one wheel, 3 wheels, doesn't matter how many wheels, the propeller now pulling wheelbarrow/airplane forward, yes the engine, if strong enough, can counteract the treadmill as it attempts to move the wheelbarrow/airplane backwards. If WB/AP is in a static position, (treadmill moving it back at same speed engine pulling it forward) it will NOT take off. IF the engine is pulling it forward, at a speed it would normally lift off at (in this case: Takeoff speed = normal rotation speed (at a given weight) + speed to overcome the treadmill's belt speed, then yes it is possible.

So if you have a treadmill that is EXTREMELY long, and the aircraft is actually making forward progress and is able to overcome the treadmill speed AND reach normal takeoff speed, then yes it is possible. If it cannot read that speed, then no, it isn't going to takeoff.
Posted By: Bad340fish

Re: Planes take off , off trailer - 07/11/20 04:52 PM

So those of you who think a plan can't take off on a treadmill.......can a plane fly over a treadmill or will it fall from the sky? Could we pull aircraft from the sky with giant treadmills on the ground?

Planes aren't wheel driven, that is why they can take off on treadmills, a plane on a treadmill will still go forward with the thrust from the propeller, the wheels might be turning at a higher rate of speed than normal but it will take off just fine.
Posted By: 360view

Re: Planes take off , off trailer - 07/12/20 11:06 AM

I am surprised no one has brought up catapults on aircraft carriers.

New electro catapult problems on USS Gerald Ford.

Truck and trailer mounted catapults for Drones.

Rocket assisted bomber take offs.
Posted By: hooziewhatsit

Re: Planes take off , off trailer - 07/12/20 05:47 PM

My point with the wheelbarrow is to try and show how what the treadmill does has no effect on whether the plane can move forward or not, when acted on by the propeller.

Yea, a plane on a treadmill without the engine running will move backwards, but only until the engine starts. Then it will move forward like it was on solid ground.
Posted By: A12

Re: Planes take off , off trailer - 07/12/20 09:56 PM

Originally Posted by 360view
I am surprised no one has brought up catapults on aircraft carriers.

New electro catapult problems on USS Gerald Ford.

Truck and trailer mounted catapults for Drones.

Rocket assisted bomber take offs.


You know that if the aircraft carrier could go fast enough to create enough wind speed to create lift on a plane sitting on a treadmill on the deck it would lift it and if you started the engine it could fly away. Brings up the fact that a vertical take-off Harrier jet could easily take off on a moving treadmill as could any plane with more forward thrust than a moving tread mill. FORWARD or upward THRUST and wind speed greater than wheel spin it will fly. Carry on catfight laugh2
Posted By: JDMopar

Re: Planes take off , off trailer - 07/17/20 02:50 AM

catfight

Attached picture Big Dad Forest.jpg
© 2024 Moparts Forums