Simple method for testing the Fluid Space Drive principle (adequate for testing other propulsion proposals)


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††††††††††† The objective of this experiment is to determine if a propeller enclosed in an airtight box can exert a force that pushes (propels) the box from the inside, and the magnitude of that force.

††††††††††† The method to be used is hanging the airtight box from the celling by four cords, comparing the position of the box at rest (propellers not activated) with the position of the box when propellers are activated (displacement) (Fig 1).




††††††††††††††††††††††††††††††††††† Fig 1

††††††††††††††††††††††††††††††††††††††††† Fig 2



Although the Fluid Space Drive proposal has been tested by various methods such as; Torsion Balancing Pendulum, Low friction surfaces, dry ice, boats on water, hanging the test box vertically and observing change when turned on, handing the test box vertically but inverted.

After all different methods have been used (the Fluid Space Drive passes ALL the tests) we are using the 4 Point Pendulum Test as recommended testing and demonstration method, it serves to demonstrate the effect and calculate working thrust.

The described experiment is inexpensive and so simple that can be done in your living room.



For the experiment you will need:


An airtight box to put the mechanism to be tested.

A motorized propeller(s) on a pedestal with R/C unit to turn propellers on/off (optional)

Two lightweight supporting beams (Fig 2)

4 cords


Description of the airtight test box.

Although we have seen a simple cardboard test box can be used (see here) we recommend the following design for consistent results that can be compared with ours (if you desire)


Fig 3


The box has the following dimensions (Fig 2)

Height 1 meter.

Length 1.4 meters.

Width 1 meter.

Plus rounded rear and forward end with a 0.5 meter radius

A box with these dimensions has a volume of 2.18 cubic meters, therefore there are 54.634.954.084.936. molecules (thatís 54 septillion [2]) very fast moving molecules colliding with each other in random manner.

Description of the motorized propeller(s) on a pedestal assembly.


††††††††††††††††† Fig 4


Fig 4 illustrates a pedestal attached to a base, the pedestal has two Lego motors and propellers (Fig 5), one of the propellers is counter rotating.

Also illustrated is a toy R/C car used to turn the propellers on/off remotely (you can use Arduinos or other system)


Although a pair of counter rotating propellers is displayed in Fig 4 the experiment can be done with only one propeller (at slightly higher RPM) when using a 4 point pendulum (Fig 2), the counter rotating propellers are necessary if you are demonstrating/testing using a balancing horizontal torsion pendulum for the test may be invalidated if the airtight box has a tendency to rotate on its vertical axis.

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Fig 5


The propellers can be constructed using an old PC power supply fan (1) with a Lego wheel (2) glued in it (Fig 5).

Cardboard cut outs (3) were attached to the power supply fan to increase size (Fig 5).

The resulting propeller was attached to a Lego Motor and installed on a pedestal inside the box (Fig 6).


Fig 6


So what can we expect? (Results)


Fig 7


Illustrated in Fig 7 is the position of the elements when the airtight box is at rest (propellers turned off), a pointer attached to the box is positioned at 0, when the propellers are turned on, if there is a force pushing inside the box the pointer will move to a position of 2 or 3 mm and stay in that position for as long as the propellers are turning, when power is switched off the box will swing to -2 or -3 mm and oscillate until it comes to a full stop (at rest)


The described setup shows sufficient displacement that can be seen by the naked eye and recorder with a simple camera and an approximate calculation of the force/thrust generated can be calculated.

For more precise calculations an analog Laser Distance Measurement Sensor would be necessary for a 0.004 mm resolution.

So how/why does this thing work again?




The box (the 2.18 cubic meter box Fig 3 was used) was hung from an altitude of 2.2 meters.

The box has a mass of 4.5 kilos.

When the propeller was turned on the box moves and maintains a distance of 3 mm

That gives us an angle of 0.0781 degrees.


Calculating useful force


If the pendulum is positioned at an angle of 0.0781 degrees, using the simple pendulum equation we see that when the pendulumís (box) velocity at the bottom of the swing is 0.000632 mps.

As the box has a mass of 4.5 kilos we can calculate a force of 28.4 millinewtons.



28.4 millinewtons is equivalent the power generated by todayís low end Ion thruster, they presently range from 28 to 250 millinewtons.

But we must remember that Ion thrusters are a mature technology, by that I mean that thousands and thousands of research and engineering hours have been invested, as has been billions of dollars.

The Fluid Space Drive is optioning similar results using only a few dollars of materials.

Also as the Fluid Space Drive does NOT expel any type of mass (no even ions) it can continue acceleration for as long as a power source is available propelling spacecraft further an faster than ever before.





This page is a work in progress (May 2019)




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