The Lafforgue's Field Propulsion Thruster
LFPT tests with smoke
tested by Jean-Louis Naudin
Cliquez ici pour la version Française
created on February 8, 2003 - JLN Labs - Last update February 9, 2003
Toutes les informations et schémas sont publiés gratuitement ( freeware ) et sont destinés à un usage personnel et non commercial

All informations and diagrams are published freely (freeware) and are intended for a private use and a non commercial use.

This is a new test about the Lafforgue's Field Propulsion Thruster ( version LFPT v1.2 ). The device used here is the same design than the previous (v1.1 ) but all potential sources of leakage current and corona effect have been eliminated by insulating fully the HV with epoxy resin and adhesive HV insulation tape.

The purpose of this test is to check if the upwards thrust observed is produced by a simple electrokinetic effect ( EHD/EKP ) and/or by an electroaerodynamic effect ( AED ).

A smoke generator ( a simple incense burning stick ) has been placed just in front of the middle of the LFPT plate. The smoke path has been observed without and with the High Voltage. If the thrust was the result of the acceleration of the air produced by an electrokinetic or electroaerodynamic thrust, the smoke flow should be sucked downwards while the LFTP goes upwards ( principle of action/reaction ).

The Lafforgue's Field Propulsion Thruster v1.2 specifications
  • Conductive Armatures :
    - Aluminum sheet, 0.5 mm thick

  • Dielectric material :
    - Epoxy resin ( dielectric constant : er=3.67 )

  • All potential sources of corona effect (tips) and leakage current have been removed by a full HV insulation.

  • Size : 70 x 105 mm

  • Working voltage : 21 KV DC ( current in the µA range )

TESTS RESULTS ( 08-02-03 ) :

The smoke flows upwards in straight line without High Voltage and without motion of the LFPT ( see the photo below )

When the High Voltage generator is switched on, the LFPT goes upwards.
The smoke is a bit attracted to the right by the motion of the LFPT surface and by the electrostatic effect,
but there is no motion of the smoke downwards ( see the photo below )

When the High Voltage is completly stopped, the LFPT keeps on oscillating for a while.
The smoke path keeps on oscillating from right to left but here only due to
the motion of the LFPT surface,
the flow is more regular than with the HV
( see the photo below ).

See the full smoke test video of the LFPT v1.2

To see the video, the free downloadable RealPlayer is required
You may download free the RealPlayer 8 Basic at :

Click on the picture above to see the video ( 777 Kb )

Comments : These interesting tests with smoke near the LFPT confirms definitely that the main thrust upwards is not generated by an electrokinetic and/or an electroaerodynamic effect because the smoke is not pulled downwards while the device goes upwards.

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