For the present stability analysis of the proptotype by means of a simulation programme, the mass inertia moments had to be known very well, because they have an important effect on the dynamic behaviour of the vehicle. For the study of the forces exerted by the ground-effect on the object, the law of Bernoully (the conservation of energy) and the law of the conservation of mass had to be applied. The time constant of the regulatory circuit of the underpressure is small and may be assumed to have appropriate damping.
This explains the high degree of inherent stability of the vehicle. It also shows that with increasing speed the overpressure on the underside of the vehicle increases exponentially. Furthermore we may remark the fast rentabilisation momentum.
The executed theoretical studies offer an explanation of the working principle of the vehicle on a normal rectilinear course and for the taking of turns, so that for these conditions the stability could be determined.
With a view to the building of the industrial prototype and its specific optimisation, a simulation programme supported by the forces of the inertia tensor suggests itself, and a structural analysis will confirm the integrity of the vehicle.
We also refer to the report of the Rijksuniversiteit  Gent, who acted as consultants on flow theory. On the whole, their report confirms our views.

The aerodynamic centre, i.e. the point around which the moment of total lift force at a determined speed remains independent from this speed, is situated relartively close to the rear of the vehicle. In any case, it is well known that this point has to be situated behind the centre of gravity in order to get longitudinal stability with respect to the directional course. This condition is clearly fulfilled. The vehicle thus achieves longitudinal stability in the normal way.
The great lateral stability can be explained by the ground-effect of the carrier wing. Between the wing and the water surface appears an overpressure . On the top side of the wing appears an underpressure, which comes from the whirls of the front rim, generated by the profile of the vehicle. With lateral inclination of the vehicle, the overpressure under the carrier wing is increased on the side, where the distance to the water is smallest and decreased on the side where that distance is greatest, whereas the stream on the upper side remains principally unaltered.
This condition creates a lateral stabilising couple. The directional stability of the vehicle  can be mainly attributed to the directional stability of its profile. Due to the presence of the water surface, the whirls produced by the carrier wing are given a horizontal direction. This, as is well known, strongly reduces the induced drift of the carrier wing. This means that even in case of possible high position angles of the vehicle, the drift remains relatively small, which has a very favourable effect on the energy consumption.

In conclusion, it may be said that the concept of the vehicle is based on very sound principles of flow mechanics. Equally it must be stressed that the vehicle makes use of a remarkable number of aerodynamic properties that contribute to its very great stability and that its industrial realisation, given adequate optimisation, will provide very high, unknown qualities of stability, manoeuvrability and agility.

The vehicle is capable of very fast unnoticed surprise operations in an extensive operational area: in regions with short waves, such as coasts, lakes, gulfs, interior lakes, rivers, large deltas,…
 
 

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