# Can centripetal/centrifugal force raise itself

## Main Question or Discussion Point

So my question is, if a laithwaite engine (my attached photo) spins fast enough, will it be able to lift off the ground?

And if yes, what's the maths to calculate the speed needed to make it lift?

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Delta2
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In order to be able to lift off, the engine must be capable of producing an aerodynamic effect such that the air pressure is higher under the engine and lower above the engine so we have a net upwards force. This engine by the looks of it isnt capable of producing much of an aerodynamic effect, no matter how fast is spinning.

To make it more clear, the two "wings" of this engine are raised due to internal forces. Internal forces cant make the engine raise as a whole, you need an external force (such as that from the air due to an aerodynamic effect) to raise the center of mass of the whole engine.

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CWatters
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So my question is, if a laithwaite engine (my attached photo) spins fast enough, will it be able to lift off the ground? And if yes, what's the maths to calculate the speed needed to make it lift?
No. Sadly Prof. Laithwaite was mistaken.

http://en.wikipedia.org/wiki/Eric_Laithwaite

In his lecture before the Royal Institution he claimed that gyroscopes weigh less when spinning and, to demonstrate this, he showed that he could lift a spinning gyroscope mounted on the end of a rod easily with one hand but could not do so when the gyroscope was not spinning. At this time, Laithwaite suggested that Newton's laws of motion could not account for the behaviour of gyroscopes and that they could be used as a means of reactionless propulsion. The members of the Royal Institution rejected his ideas and his lecture was not published.