Paravane (water kite)


The paravane is a towed winged underwater object—a water kite. Paravanes have been used in sport or commercial fishing, marine exploration and industry, sports and military. The wings of paravanes are sometimes in a fixed position, else positioned remotely or by actions of a human pilot. Pioneer parafoil developer Domina Jalbert considered water kites hardly different from air kites. However, paravanes generally orient themselves in respect to the water surface. They may have sensors that record or transmit data or be used entirely for generating a holding force like a sea anchor does. While a sea-anchor allows a vessel to drift more slowly downwind, the paravane travels sideways at several times the downwind speed. Paravanes are, like air kites, often symmetrical in one axis and travel in two directions, the change being effected by gybing, shunting, or flipping over.

Military applications

The paravane weapon was developed by the British inventor Sir Dennistoun Burney as a means to sweep enemy mines. Towed behind a ship, the paravane wire would either cut the mine's mooring cable or bring the mine and paravane together, detonating the mine. There are offensive and defensive paravanes. There are main paravanes and auxiliary protector paravanes. Some paravanes are equipped with cable cutters that cut the moored mines. Explosive paravanes are essentially a towable or controllable mine. The US Department of Defense continues to have

Abstract : A paravane includes an elongated fuselage; a wing section of spaced wing members attached to an intermediate portion of the fuselage; stabilizer fins for maintaining the paravane lined-up with the direction of tow; a depth control flap positioned adjacent the wing section and having a pivot axis extending closely adjacent to the towing point; and depth control means of controlling the position of the control flap. The wing members have a straight leading edge portion, a straight trailing edge portion and a curved intermediate portion wherein the wing members are arranged such that the chord lines extend at oblique angles with the longitudinal axis of the fuselage and such that the resultant hydrodynamic lift force vector acting on the wing section passes through the tow point.

In commercial fishing

There are arrowhead paravanes, flexi-wing paravanes, and bi-wing paravanes; these water kites are used in tuna fishing operations.
Trolling-for-fish devices that are paravanes or water kites do not always use the descriptor;
George Dahl in 1957 taught how to kite his device underwater in order to place bait at the desired depth; and he wanted to have a boat have several of the devices being towed at the same time without the devices and bait interfering with each other—so his device was able to be set for different deflections, that is, the various water kites would be set to fly in the water at specified positions.

In marine industry

Water kites help depress cables being placed as well as other payloads.

In sport fishing

In 1905 Martin Flegle of Minneapolis, Minnesota, invented a lighter-than-water water kite that could be operated from boats or from the shoreline for the purpose of trolling for fish. The paravane would float on the surface of the water, but the vaning was in the water. The device would move oblique to the towing effort. His device's operation had a way to fully change directions.
Paravanes carry bait to specific depths. Some fishing lures are themselves paravanes.

In sports and play

Towed human-on-board paravanes are used to transport explorers, SCUBA sportsmen, spear-fishing people.
Speedsailing has been driving the use of water kites. A group has developed an air kite that dynamically was coupled with a water kite that they also developed: FRENCH
L'aile d'eau . Similar technology is found in Yellow Pages Endeavour; such speed record efforts are related to the . The is a water kite hydrofoil tugged by an air kite reaching for breaking speed sailing records. A . The kite on the Jellyfish Foiler gives tension through a rigidized tether pulling on the water-kite hydrofoil hydrodynamic center in order to avoid roll. The Jellyfish Foiler lower hydrofoil has two J-shaped foils and one center T-foil rudder and is pulled by the upper air kite; the system is a closely coupled double-kite system resulting in a system that will fly through the air and water in an effort to break the 50-knot speed sailing record.

In science

Paravanes are used for sampling water chemistry; controlled kiting to specific depths allow scientists to map water qualities in the oceans and lakes of the world.
An array of pontoon paravanes' wings are set so each water kite positions itself so it does not interfere with the others. One use has been the holding of seismic instruments.

Patents