The Lafforgue's Field Propulsion Thruster Solver
By Jean-Louis Naudin
created on February 1, 2002 - JLN Labs - Last update February 4, 2002
All informations in this page are published free and are intended for private/educational purposes and not for commercial applications

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The Lafforgue's FPT solver v2.01 - By JL Naudin - Updated February 4, 2002
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Note: This new solver uses an improved version ( more accurate ) of the Lafforgue's original equation, if want to use the old solver version which uses the original Lafforgue's equation presented in his patent you may click here.

Click here to see all the details about the Lafforgue's theory and its principle

eo -permittivity of free space (coul/Vm) :
Asymmetrical capacitor specifications
er – dielectric permittivity : (1) e - dielectric gap (mm) : (2)
Ra - alpha radius ( mm ) : (3) L - capacitor thickness ( m ) : (4)
Power supply specification
V - voltage ( V ) : (5)

Capacitor sizes ( calculated ) :
D - ( mm ): F - ( mm ): H - ( mm ):
W - LFPT wide ( mm ): Rb - beta radius ( mm ):
AREA - A :
Fa - force (N) :
C - capacitance (1x1/4 cylinder) (F) : q - charge (1x1/4 cylinder) (C) :
Fja - thrust (1x1/4 cylinder) (N) : Fjb - thrust (1x1/4 cylinder) (N) :
Fc - total thrust (2x1/4 cylinders) (N) :

F - Resulting THRUST (N) :

Material Dielectric constant ( K ) Dielectric Strength ( V/m )
Air 1.00059 3e6
Teflon 2.1 60e6
Styrene HIPS 2.56 24e6
Nylon 3.00 14e6
Bakelite 3.7 24e6
Kapton 4.2 11.8e7
Neoprene rubber 6.7 12e6
Strontium Titanate 233 8e6
Barium Strontium Titanate ( BaSrTiO3 ) 13800 10e7

I encourage anyone who wants to conduct some researches in this domain, to study the Lafforgue's patent FR2651388 very carefully....
Some translations of the Lafforgue's patent can be found

Isolated systems self-propelled by electrostatic forces  by Jean-Claude Lafforgue ( France )
No. Publication (Sec.) : FR2651388 
Date de publication : 1991-03-01  
The electrostatic forces are "generated" by the interaction of polarised atoms (q) on an electric vector field (E), i.e. F=q.E, positive or negative according to the sign of (q). By suitable geometry of the polarised armatures, and/or by the use of electric charges induced by induction effect, and/or by the use of suitably arranged dielectrics, it becomes possible to break the symmetry of the expansion forces on one of the axes of the three-axis reference system and thus to obtain a non-zero resultant force (Fn). The isolated system is then propelled, and it draws the charges (q) and (E) along with it, thus F=q.E remains constant. This force can be used as a means of propulsion for any vehicle or even as motive force for producing energy.

The LFPT explained : Theory and Principle

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