## Can a sealed drone fly into space?

Discussions related to engineering and its applications. From civil and mechanical to aeronautic and robotics, etc.

### Re: Can a sealed drone fly into space?

I think what MyUncle might be missing here is a basic understanding of the forces and reactions at play.

When the blades of a helicopter turn, they push down against the air, the air pushes against the ground, the ground pushes back against the air, then the air in turn pushes back against the blades, which creates the upwards lift that elevates the helicopter (or drone).

Conversely, if you put a fan on the ground face up and turn it on, the fan will push against the ground, and it's blades will push upwards against the air. If you put an object over the fan, the air from the fan will push against the object. If this push is bigger than the weight of the object, the object will be lifted up.

Now take that and apply it to a drone enclosed inside a solid sphere placed on the ground. When the drone's fans turn, they will push air down, the air pushes against the bottom of the sphere, the sphere pushes back on the air, the air pushes back against the drone's propeller causing the drone to rise inside the sphere. If the drone rises up until it hits the top side of the sphere, it will begin to exert an upwards force on the top side of the sphere. However, this force would be equal to the downward force created by the air being pushed by the propeller towards the bottom of the sphere, causing the sphere to remain in place.

Think about it in yet another way. If you're standing inside a big box, and you push against one of the sides, will that cause the box to start sliding around? Nope. That's because the force you're applying to the side of the box is counterbalanced by the opposing push of your feet (assume the box is sturdy enough that it doesn't fall apart). In order to move the box itself, you'll have to push against something outside of the box, to create a net force over the box (such as pushing against the box from the ouside with your feet on the ground).

In other words, putting a drone inside a sphere doesn't solve anything for your problem. It simply traps the drone.

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### Re: Can a sealed drone fly into space?

Well yes Z, there is the force from the fan backwards and with little resistance, in the equal and opposite direction, the train move forward. But I don't think it is a plane.

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### Re: Can a sealed drone fly into space?

Watson » Sun Jul 03, 2016 12:58 pm wrote:Well yes Z, there is the force from the fan backwards and with little resistance, in the equal and opposite direction, the train move forward. But I don't think it is a plane.

attach wings and spin the prop fast enough if it goes into the air it's a plane. I think i even saw a model remote control plane in the shape of a skateboard once.

we are just debating the definition of an airplane.

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### Re: Can a sealed drone fly into space?

Hi all,

Here is a short fun video (watch it first to demonstrate MyUncle's idea):

Now watch this Secret Video to see the explanation of the above video (click on link below):

BioWizard has it correct. The forces are contained inside the box.

Best Regards,
Dave :^)
Last edited by zetreque on July 5th, 2016, 3:32 pm, edited 1 time in total.
Reason: made both videos appear.

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### Re: Can a sealed drone fly into space?

And that's why it's called a box! ;]

I hope the videos humor the readers without confusing them too much. The first one was a hoax, and the second one explains the hoax and shows that the weight doesn't actually change.

Thanks Dave.

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### Re: Can a sealed drone fly into space?

I wouldn't expect that little quadcopter to lift such a box...but try with a carrier bag, attach 4 barbecue sticks to the copter so it won't touch the bag, and let's see what happens :)
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### Re: Can a sealed drone fly into space?

Myuncle » 05 Jul 2016 05:26 am wrote:I wouldn't expect that little quadcopter to lift such a box...but try with a carrier bag, attach 4 barbecue sticks to the copter so it won't touch the bag, and let's see what happens :)

Same.

The point wasn't that the quad didn't lift the box - nobody expected it to. It was that it couldn't decrease the weight of the box (i.e. could not exert any lift). If you can't get any lift using this set up, then it doesn't matter how low the weight of the container goes - no lift means no lift.

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### Re: Can a sealed drone fly into space?

Myuncle » Tue Jul 05, 2016 10:26 am wrote:I wouldn't expect that little quadcopter to lift such a box...but try with a carrier bag, attach 4 barbecue sticks to the copter so it won't touch the bag, and let's see what happens :)
Your idea is charming, but basic physics prevents it from working. The physics has been explained in different ways by several others. What do you still not understand? We can try to explain it differently.
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### Re: Can a sealed drone fly into space?

Myuncle » July 5th, 2016, 3:26 am wrote:I wouldn't expect that little quadcopter to lift such a box...but try with a carrier bag, attach 4 barbecue sticks to the copter so it won't touch the bag, and let's see what happens :)

As pointed out, the weight of the box is not the point. If you performed this experiment with the quadcopter a bit above the box and attached to the box by strings, the upward thrust of the quad copter would cancel out part of the weight of the box, lowering the scale reading. Putting the quad copter in the box, shows no change in the scale.

This is because of the way the copters produce their own lift. The blades push downward on the air propelling the air downward, which in turn produces an upward action-reaction force on the blades which is transfered to the copter as a whole. In the box, the air travels downward, until it hits the bottom of the box, causing a downward force on the box, which is transferred to the copter by the lines attaching them to each other. This downward force cancels out the upwards force produced by the blade, resulting in no net upward thrust or movement.

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### Re: Can a sealed drone fly into space?

JMP1958 » July 5th, 2016, 11:50 am wrote:
Myuncle » July 5th, 2016, 3:26 am wrote:I wouldn't expect that little quadcopter to lift such a box...but try with a carrier bag, attach 4 barbecue sticks to the copter so it won't touch the bag, and let's see what happens :)

As pointed out, the weight of the box is not the point. If you performed this experiment with the quadcopter a bit above the box and attached to the box by strings, the upward thrust of the quad copter would cancel out part of the weight of the box, lowering the scale reading. Putting the quad copter in the box, shows no change in the scale.

This is because of the way the copters produce their own lift. The blades push downward on the air propelling the air downward, which in turn produces an upward action-reaction force on the blades which is transfered to the copter as a whole. In the box, the air travels downward, until it hits the bottom of the box, causing a downward force on the box, which is transferred to the copter by the lines attaching them to each other. This downward force cancels out the upwards force produced by the blade, resulting in no net upward thrust or movement.

I understand what you are saying, but the force of the air propelled downward it might not be as strong as the upward force, or if it's exactly the same, there might be ways of shaping the inside of the box in a way that the air can be slowed down, or placing a felt blanket with lots of holes, to absorb the air impact. Anyway, I am just mucking around, would be nice to see a clip with a bigger drone and a carrier bag.
Last edited by Myuncle on July 5th, 2016, 1:32 pm, edited 1 time in total.
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### Re: Can a sealed drone fly into space?

Myuncle » July 5th, 2016, 10:16 am wrote:
JMP1958 » July 5th, 2016, 11:50 am wrote:
Myuncle » July 5th, 2016, 3:26 am wrote:I wouldn't expect that little quadcopter to lift such a box...but try with a carrier bag, attach 4 barbecue sticks to the copter so it won't touch the bag, and let's see what happens :)

As pointed out, the weight of the box is not the point. If you performed this experiment with the quadcopter a bit above the box and attached to the box by strings, the upward thrust of the quad copter would cancel out part of the weight of the box, lowering the scale reading. Putting the quad copter in the box, shows no change in the scale.

This is because of the way the copters produce their own lift. The blades push downward on the air propelling the air downward, which in turn produces an upward action-reaction force on the blades which is transfered to the copter as a whole. In the box, the air travels downward, until it hits the bottom of the box, causing a downward force on the box, which is transferred to the copter by the lines attaching them to each other. This downward force cancels out the upwards force produced by the blade, resulting in no net upward thrust or movement.

I understand what you are saying, but the force of the air propelled downward it might not be as strong as the upward force, or if it's exactly the same, there might be ways of shaping the inside of the box in a way that the air can be slowed down. Anyway, I am just mucking around, would be nice to see a clip with a bigger drone and a carrier bag.

No it can't. Any means of slowing the air would have to be attached to the box/copter pair, and would transfer a downward force on the whole affair. Even the fact that the downward moving air will be slowed by interacting with other air in the box doesn't help because it can only do so by transferring some of its downward motion to the other air. The air is moving at a slower downward speed but there is more of it moving downward, so its effect on the box is the same.

It like what someone above already said, it is like trying to lift yourself by your own bootstraps; no matter how hard you try or how complicated the apparatus you use, you can not exert more force upward on your feet than is being exerted downward on your body by your arms. There is no way around this or any way that you can "trick" the laws of physics to make it possible.

It is as immutable as the fact that you cannot have object A touching object B without object B touching object A.

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### Re: Can a sealed drone fly into space?

Dave_Oblad » Mon Jul 04, 2016 1:59 pm wrote:

BioWizard has it correct. The forces are contained inside the box.

Best Regards,
Dave :^)

Thank for the video Dave. I really would have thought it would answer it once and for all. Perhaps the hoax confused things. I'm quoting your real video again. :]

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### Re: Can a sealed drone fly into space?

JMP1958 » Tue Jul 05, 2016 9:50 am wrote:
Myuncle » July 5th, 2016, 3:26 am wrote:I wouldn't expect that little quadcopter to lift such a box...but try with a carrier bag, attach 4 barbecue sticks to the copter so it won't touch the bag, and let's see what happens :)

As pointed out, the weight of the box is not the point. If you performed this experiment with the quadcopter a bit above the box and attached to the box by strings, the upward thrust of the quad copter would cancel out part of the weight of the box, lowering the scale reading. Putting the quad copter in the box, shows no change in the scale.

This is because of the way the copters produce their own lift. The blades push downward on the air propelling the air downward, which in turn produces an upward action-reaction force on the blades which is transfered to the copter as a whole. In the box, the air travels downward, until it hits the bottom of the box, causing a downward force on the box, which is transferred to the copter by the lines attaching them to each other. This downward force cancels out the upwards force produced by the blade, resulting in no net upward thrust or movement.

Kinda like this, but with a string attached.

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### Re: Can a sealed drone fly into space?

Another example. Mount a fan on a skateboard. The fan is blowing air towards the back of the skateboard. Where will the skateboard go? Forward. Now, seal the fan inside a box, mount it on the skateboard like before, turn on the fan for only three seconds: where will the skateboard move? Forward, backwards, or nowhere?
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### Re: Can a sealed drone fly into space?

Myuncle » 05 Jul 2016 03:57 pm wrote:Another example. Mount a fan on a skateboard. The fan is blowing air towards the back of the skateboard. Where will the skateboard go? Forward. Now, seal the fan inside a box, mount it on the skateboard like before, turn on the fan for only three seconds: where will the skateboard move? Forward, backwards, or nowhere?

That's nothing new is it? After all, we do see the drone rise from the bottom of the box to the top of the box. And yet nothing happens to the weight.

What you need to understand here is that the limitation for what you're proposing is the laws of physics - not a design element.

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### Re: Can a sealed drone fly into space?

Try to think about all the forces acting on the system in detail. Don't just try to run a fuzzy simulation in your head. Intuition can fool you. Think about the problem rigorously and draw out the forces if you need to. There's a lot of good explanations here to start from. You'll quickly see why it can't work. Start with the simplest model - a solid box. Don't worry about the bag for now, that's a lot more complicated, despite the fact that it suffers the same limitation.

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### Re: Can a sealed drone fly into space?

Myuncle » July 5th, 2016, 1:57 pm wrote:Another example. Mount a fan on a skateboard. The fan is blowing air towards the back of the skateboard. Where will the skateboard go? Forward. Now, seal the fan inside a box, mount it on the skateboard like before, turn on the fan for only three seconds: where will the skateboard move? Forward, backwards, or nowhere?

Net movement will be nowhere. Now at first, you might get a slight shift forward as the fan moves air from one side of the box to the other creating a pressure differential and a shift in the center of mass for the box-fan-skateboard. But once the fan shuts off, the air will equalize again shifting everything back to the starting position for no net movement.

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### Re: Can a sealed drone fly into space?

JMP1958 » July 5th, 2016, 4:53 pm wrote:
Myuncle » July 5th, 2016, 1:57 pm wrote:Another example. Mount a fan on a skateboard. The fan is blowing air towards the back of the skateboard. Where will the skateboard go? Forward. Now, seal the fan inside a box, mount it on the skateboard like before, turn on the fan for only three seconds: where will the skateboard move? Forward, backwards, or nowhere?

Net movement will be nowhere. Now at first, you might get a slight shift forward as the fan moves air from one side of the box to the other creating a pressure differential and a shift in the center of mass for the box-fan-skateboard. But once the fan shuts off, the air will equalize again shifting everything back to the starting position for no net movement.

So you say that the skateboard will go forward and then backwards at the end of the three seconds? I think it just will go forward, slowly, but it will go only in one direction, thanks to pulses. On and off, on and off. A pulsejet engine (or pulse jet) is a type of jet engine in which combustion occurs in pulses. Why not to try something similar to a sealed drone?
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### Re: Can a sealed drone fly into space?

Myuncle » Tue Jul 05, 2016 3:15 pm wrote:
JMP1958 » July 5th, 2016, 4:53 pm wrote:
Myuncle » July 5th, 2016, 1:57 pm wrote:Another example. Mount a fan on a skateboard. The fan is blowing air towards the back of the skateboard. Where will the skateboard go? Forward. Now, seal the fan inside a box, mount it on the skateboard like before, turn on the fan for only three seconds: where will the skateboard move? Forward, backwards, or nowhere?

Net movement will be nowhere. Now at first, you might get a slight shift forward as the fan moves air from one side of the box to the other creating a pressure differential and a shift in the center of mass for the box-fan-skateboard. But once the fan shuts off, the air will equalize again shifting everything back to the starting position for no net movement.

So you say that the skateboard will go forward and then backwards at the end of the three seconds? I think it just will go forward, slowly, but it will go only in one direction, thanks to pulses. On and off, on and off. A pulsejet engine (or pulse jet) is a type of jet engine in which combustion occurs in pulses. Why not to try something similar to a sealed drone?

You are now dipping into the physics of friction (in this case the bearings in the skateboard wheels, wheels against the ground, or container against the air). When you understand friction, you will understand why the net force still comes out to zero. If we go back to the original drone in a box situation, air friction is going to be so small that the effect of friction will be even more negligible (especially as you near space).

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### Re: Can a sealed drone fly into space?

It's like if you sit in a swivel chair that can spin all the way around. If you give your body a jolt you will overcome the friction in the bearings and spin the chair. Then you slowly move your body back to it's original position without overcoming the friction force. Then you can give it a good jolt again.

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### Re: Can a sealed drone fly into space?

Myuncle » July 5th, 2016, 3:15 pm wrote:
JMP1958 » July 5th, 2016, 4:53 pm wrote:
Myuncle » July 5th, 2016, 1:57 pm wrote:Another example. Mount a fan on a skateboard. The fan is blowing air towards the back of the skateboard. Where will the skateboard go? Forward. Now, seal the fan inside a box, mount it on the skateboard like before, turn on the fan for only three seconds: where will the skateboard move? Forward, backwards, or nowhere?

Net movement will be nowhere. Now at first, you might get a slight shift forward as the fan moves air from one side of the box to the other creating a pressure differential and a shift in the center of mass for the box-fan-skateboard. But once the fan shuts off, the air will equalize again shifting everything back to the starting position for no net movement.

So you say that the skateboard will go forward and then backwards at the end of the three seconds? I think it just will go forward, slowly, but it will go only in one direction, thanks to pulses. On and off, on and off. A pulsejet engine (or pulse jet) is a type of jet engine in which combustion occurs in pulses. Why not to try something similar to a sealed drone?

Pulse jets still work by transferring momentum to something external to the jet itself; the surrounding air.

The only way to get something like your skate board to move in one direction and not shift back by using pulses to to take advantage of the difference between static and kinetic friction. For example, let's say that you are standing on a wheeled cart, and suddenly shift your weight backward while pushing the cart forward. You then slowly shift your weight forward again, so that the cart does not move back, and repeat.

While it is possible to get the cart to creep forward using this attempt, it isn't by getting around the conservation of momentum. The is a difference between static friction (the friction caused by getting something moving) vs. kinetic friction ( the friction acting on a moving object). When you shift your weight quickly, you are generating enough force to overcome the static friction keeping the wheels from turning. Once rolling, the lesser kinetic friction allows the wheels to roll for a bit before coming to a stop. If you now shift your weight slowly back in the other direction, and if you do it gently enough you can keep the force less than the static friction and the cart will not roll backward. But now what you are really doing is transferring your momentum through the non turning wheels to the Earth itself. IOW, your net forward motion is due to transferring motion to something external to you and the cart.

Now for something in the air, things work a bit differently. Here fast motion creates more friction than slow motion. So just maybe you might be able to take advantage of this by trying to jerk your box quickly in one direction and slowly in the other, with a net motion opposite of the example above, you are still doing it by transferring momentum from the box to the outside air. Remove the outside air for the box to push against and you get no net movement.

You cannot generate net movement with a closed system. The way the universe is put together will not allow it, and the universe does not care if you disagree.

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### Re: Can a sealed drone fly into space?

JMP1958 » July 5th, 2016, 6:51 pm wrote: Remove the outside air for the box to push against and you get no net movement.

You can try the same skateboard experiment inside a vacuum chamber, all the air is removed, and in that case I think the skateboard will move even faster.
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### Re: Can a sealed drone fly into space?

Hi MyUncle,

I suspect almost every Science Geek (like me) has stood on a skateboard and proved they could get it to roll on level ground by a series of jerky motions and never touching the ground with their feet. But really, all they are doing is playing with the dynamics of friction.. as explained already.

If you are looking for a free lunch.. you need to get into Quantum Mechanics. That's the domain where one might find a technique to obtain free energy. Hey.. the Universe did it.. so why can't we?

If you want a propulsion system that defies conventional Science then check out this:
https://en.wikipedia.org/wiki/RF_resonant_cavity_thruster

Best wishes,
Dave :^)

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### Re: Can a sealed drone fly into space?

Fan propulsion in a sealed bag. This is a classic violation of Conservation of Momentum. The skateboard moving forward must be met with an "equal and opposite reaction" in the air passing the fan blades. If the bag is sealed, the "equal-and-opposite" reaction of the air will then blow on the bag's inside surface. The bag itself will then do an equal-and-opposite reaction from being hit with air. You will notice this happens to move the entire bag in the opposite direction of the skateboard's forward motion.

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### Re: Can a sealed drone fly into space?

Dave_Oblad » July 5th, 2016, 9:34 pm wrote:Hi MyUncle,

I suspect almost every Science Geek (like me) has stood on a skateboard and proved they could get it to roll on level ground by a series of jerky motions and never touching the ground with their feet. But really, all they are doing is playing with the dynamics of friction.. as explained already.

If you are looking for a free lunch.. you need to get into Quantum Mechanics. That's the domain where one might find a technique to obtain free energy. Hey.. the Universe did it.. so why can't we?

If you want a propulsion system that defies conventional Science then check out this:
https://en.wikipedia.org/wiki/RF_resonant_cavity_thruster

Best wishes,
Dave :^)

Thanks Dave I will read it (and try to understand as much as I can...)
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### Re: Can a sealed drone fly into space?

hyksos » July 6th, 2016, 2:25 am wrote:Fan propulsion in a sealed bag. This is a classic violation of Conservation of Momentum. The skateboard moving forward must be met with an "equal and opposite reaction" in the air passing the fan blades. If the bag is sealed, the "equal-and-opposite" reaction of the air will then blow on the bag's inside surface. The bag itself will then do an equal-and-opposite reaction from being hit with air. You will notice this happens to move the entire bag in the opposite direction of the skateboard's forward motion.

Why? A long bin bag. On each 3 seconds pulse, one end of the bag is right behind the fan, the other end of the bag is far away from the fan. When the air is blowed, it will reach the opposite end of the bag at a certain speed, when the air goes back it will be much slower, so the skateboard will move mostly on one direction. No?
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### Re: Can a sealed drone fly into space?

Myuncle, In a frictionless situation, you may see micro-movements where the system lurches a centimeter forward, but after the air circulates around the bag , the plastic will 'pop' and move the whole system back to its original location. You will never make substantial forward motion, because that would violate conservation of momentum.

The only way for this skateboard-bag-fan system to make forward progress would be to apply friction somehow against the ground. Somehow through the wheels.

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### Re: Can a sealed drone fly into space?

Myuncle » July 6th, 2016, 2:35 am wrote:
hyksos » July 6th, 2016, 2:25 am wrote:Fan propulsion in a sealed bag. This is a classic violation of Conservation of Momentum. The skateboard moving forward must be met with an "equal and opposite reaction" in the air passing the fan blades. If the bag is sealed, the "equal-and-opposite" reaction of the air will then blow on the bag's inside surface. The bag itself will then do an equal-and-opposite reaction from being hit with air. You will notice this happens to move the entire bag in the opposite direction of the skateboard's forward motion.

Why? A long bin bag. On each 3 seconds pulse, one end of the bag is right behind the fan, the other end of the bag is far away from the fan. When the air is blowed, it will reach the opposite end of the bag at a certain speed, when the air goes back it will be much slower, so the skateboard will move mostly on one direction. No?

No. The only reason that the air slows down is because it is colliding with the air between the fan ans the far end of the bag and transferring some of its momentum to it. You get slower moving air, but more of it and the total momentum is the same which will exactly cancel out the initial movement the skate board might have had.

The law of conservation of momentum is inviolate. It can not be broken.(Noether's theorem even goes as far as to prove that the universe requires such conservation laws to exist.) Your intuition dos not trump 100's of years of scientific experimentation. Why can't you just accept that your idea is based on misconceptions on your part?

It's not as if you are the first person to suggest such an idea. I've been seeing them crop up ever since I started browsing the internet, and I'm sure that they predate that. Why do you think that no one in all that time has ever produced a working model? It is because the basic idea is flawed. If it wasn't, we'd already be using fans inside of sealed containers to propel spacecraft.

It's time to swallow your pride, accept that you are wrong, learn from the experience, and move on.

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### Re: Can a sealed drone fly into space?

JMP1958 » July 6th, 2016, 10:55 am wrote:
Myuncle » July 6th, 2016, 2:35 am wrote:
hyksos » July 6th, 2016, 2:25 am wrote:Fan propulsion in a sealed bag. This is a classic violation of Conservation of Momentum. The skateboard moving forward must be met with an "equal and opposite reaction" in the air passing the fan blades. If the bag is sealed, the "equal-and-opposite" reaction of the air will then blow on the bag's inside surface. The bag itself will then do an equal-and-opposite reaction from being hit with air. You will notice this happens to move the entire bag in the opposite direction of the skateboard's forward motion.

Why? A long bin bag. On each 3 seconds pulse, one end of the bag is right behind the fan, the other end of the bag is far away from the fan. When the air is blowed, it will reach the opposite end of the bag at a certain speed, when the air goes back it will be much slower, so the skateboard will move mostly on one direction. No?

No. The only reason that the air slows down is because it is colliding with the air between the fan ans the far end of the bag and transferring some of its momentum to it. You get slower moving air, but more of it and the total momentum is the same which will exactly cancel out the initial movement the skate board might have had.

The law of conservation of momentum is inviolate. It can not be broken.(Noether's theorem even goes as far as to prove that the universe requires such conservation laws to exist.) Your intuition dos not trump 100's of years of scientific experimentation. Why can't you just accept that your idea is based on misconceptions on your part?

It's not as if you are the first person to suggest such an idea. I've been seeing them crop up ever since I started browsing the internet, and I'm sure that they predate that. Why do you think that no one in all that time has ever produced a working model? It is because the basic idea is flawed. If it wasn't, we'd already be using fans inside of sealed containers to propel spacecraft.

It's time to swallow your pride, accept that you are wrong, learn from the experience, and move on.

I don't have problems to "swallow my pride", lol, have you got a personality disorder? Why don't you calm down a little bit? Are you capable of a civilized discussion without being so annoyingly patronizing? If you are not cabable of doing that, I suggest you to seek professional help, rather than thinking about science. And anyway, if everyone had to think your bigoted way, we would be still living in the caves, with zero progress. Please, have the decency to stop trolling now.
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### Re: Can a sealed drone fly into space?

Myuncle » Wed Jul 06, 2016 4:11 pm wrote:I don't have problems to "swallow my pride", lol, have you got a personality disorder? Why don't you calm down a little bit? Are you capable of a civilized discussion without being so annoyingly patronizing? If you are not cabable of doing that, I suggest you to seek professional help, rather than thinking about science. And anyway, if everyone had to think your bigoted way, we would be still living in the caves, with zero progress. Please, have the decency to stop trolling now.
JMP has actually given you some sound advice. Basically your proposal has two primary characteristics, one negative, one positive.

The positive one is that it is imaginative and well intentioned.

The negative one is that it won't work. This is not a matter of being close minded, but of recognising some fundamental principles of science that have been tested not once, not a hundred times, not a million times, but through the application of technology, many billions of times. Insisting it is otherwise is foolish.

Several members have attempted various ways of explaining this to you. You have chosen to ignore these explanations. You have every right to ignore these, but only if you wish to remain ignorant. I strongly recommend that you re-read the explanations and return with questions based on what remains unclear.

In Moderator Mode: Please discontinue making personal remarks about other members. Do not respond to this portion of this post in this thread. If you have an issue with this advice PM me, or another mod or admin. Thank you.

Edited some unconscionable typographical nonsense involving mixing up "is" and "it".
Eclogite
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