GB2098950A

GB2098950A - Launching tethered sails for marine or other uses

Info

Publication number: GB2098950A
Application number: GB8214706A
Authority: GB
Original assignee: BP PLC
Current assignee: BP PLC
Priority date: 1981-05-21
Filing date: 1982-05-20
Publication date: 1982-12-01

Abstract

Launching of a spar-less elevated sail 5 is achieved by packing the sail into a launching container 4, the sail being attached via a line 8 to a winch 2. The sail 5 is then connected to a pilot kite 7 through a line 6. Upon release the pilot kite 7 draws the spar- less sail 5 from the launch container 4 under the control of the winch. The pilot kite 7 may be released, using a compressed air launcher 3 or by direct deployment and the container 4 may have gas inflation equipment for inflating the sail 5 as it is withdrawn. <IMAGE>

Description

SPECIFICATION Elevated sails The present invention relates to elevated sails and more particularly to the deployment of elevated sails for the propulsion of water going vessels.

The ever increasing cost of energy particularly in the form of increasing oil prices have led to renewed interest in the total or partial propulsion of water going vessels such as cargo ships, tankers and yachts by use of wind energy. In particular, elevated sails or kites which have been proposed and used for the propulsion of ships have certain advantages over, say, vessel mounted sails. These advantages include the ability to fly at an altitutde where the winds are generally stronger and more stable than those close to the ground.

The present invention relates to improved means for the launch, and recovery of elevated sails suitable for use in the total or partial propulsion of water going vessels. The use of the term sail is intended to include elevated sails and any tethered flying surface.

Thus, according to the present invention, there is provided a method of launching a spar-less elevated sail comprising the steps of (a) packing the sail into a launching container or the like, the sail being attached to a restraint means (b) connecting the sail to a pilot kite by means of a line (c) the pilot kite being adapted on release to fly and withdraw the spar-less elevated sail from the launching container under control of the restraint means. The spar-less kite may be recovered by operation of the restraint means, e.g. a winch, which pulls the kite down and back into the launch gun for subsequent use.

The invention also includes an elevated sail assembly comprising (a) a spar-less elevated sail capable of launching from (b) a launching container or the like (c) a pilot kite capable of attachment to the elevated sail (d) means for launching the pilot kite and (e) restraint means capable of attachment to the elevated sail while in the launching container.

Elevated sails may also be used to provide aerial platforms to lift equipment for photography, surveying, air pollution monitoring, gas sampling, crop spraying, radar operation or communications. Where loads to be supported exceed a weight of several kilograms the sizes of the kites then required can result in line forces in excess of those readily manhandled.

The invention will now be described by way of example only. A ship 1 has a winch system 2 on its deck. Nearby on the deck are located a compressed air driven pilot kite launch gun 3 and a container in the form of an extended hollow cylinder 4. The container 4 is adapted to hold a spar-less kite 5 in the form of a bundle and may be passive or blown by a fan or compressed air.

During launch of the elevated sail the elevated sail bundle 5 is positioned in the container 4.

Alongside, a pilot kite is positioned in the launch gun 3. A crown line 6 is attached from the pilot kite 7 to the kite bundle 5. The bundle 5 is also attached to the winch system 2 by means of a control line 8.

When the sail system is required, the pilot parachute kite 7 is deployed using the compressed air launcher 3 or by direct deployment from the deck. When sufficient pilot line has been paid out to ensure that the pilot kite 7 is pulling its line in a stable manner the line 6 is attached to the upper surface of the elevated sail (figure 1 a). The optimum attachment position varies with the design of sail. For example, an essentially round canopied sail may be pulled from its mid point or crown (figure 1 b) whilst a ram air wing sail may be iifted with a bridle 1 of two or more lines from its top surface (figure 1 c).

The elevated sail 5 is released from the container by allowing the restraining winch 2 to pay out. As the sail 5 begins to clear the mouth of the container 4 (figure 1 b) it will begin to inflate due to local air movements around the vessel.

This movement from the container and subsequent inflation may be assisted by gas pumped into the container through manifolds 9 or ejected through slots or jets 10 at the container mouth (figure 1 b).

With the sail 5 inflated by these means, the control line 8 is paid out until the sail 5 is at the desired height. The pilot kite 7 may be left flying if required or be released from the sail 5 by use of a light trigger line to a snap shackle (or similar) and brought back to the ship (not shown).

If the method of launching using gas pumped into the container or jets or slots at the container mouth is carried out with sufficient gas, the elevated sail system may be deployed without any use of pilot kites as the gas jets will counteract the turbulent air flow around the deck of the ship.

To recover the sail 5, the restraining winch 2 is used to reel in the flying line 8 so that the shrouds 12 of the sail 5 enter the mouth of the container 4 (which is preferably a smooth fair shape to reduce the possibility of chafing) and the sail is deflated ready for storage until it is required again.

The instability sometimes experienced by the sail as it approaches the ship during recovery due to air turbulence may be alleviated by relaunching the pilot kite and attaching it to the crown line of the main kite.

Where the towing force due to one sail is insufficient the above methods may be duplicated with a series of containers to deploy sail at intervals either by use of single line or alternatively by the use of separate adjacent lines.

Claims

1. A method of launching a spar-less elevated sail comprising the steps of (a) packing the sail into a launching container or the like, the sail being attached to a restraint means (b) connecting the sail to a pilot kite by means of a line (c) the pilot kite being adapted on release to fly and withdraw the spar-less elevated sail from

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Elevated sails The present invention relates to elevated sails and more particularly to the deployment of elevated sails for the propulsion of water going vessels. The ever increasing cost of energy particularly in the form of increasing oil prices have led to renewed interest in the total or partial propulsion of water going vessels such as cargo ships, tankers and yachts by use of wind energy. In particular, elevated sails or kites which have been proposed and used for the propulsion of ships have certain advantages over, say, vessel mounted sails. These advantages include the ability to fly at an altitutde where the winds are generally stronger and more stable than those close to the ground. The present invention relates to improved means for the launch, and recovery of elevated sails suitable for use in the total or partial propulsion of water going vessels. The use of the term sail is intended to include elevated sails and any tethered flying surface. Thus, according to the present invention, there is provided a method of launching a spar-less elevated sail comprising the steps of (a) packing the sail into a launching container or the like, the sail being attached to a restraint means (b) connecting the sail to a pilot kite by means of a line (c) the pilot kite being adapted on release to fly and withdraw the spar-less elevated sail from the launching container under control of the restraint means. The spar-less kite may be recovered by operation of the restraint means, e.g. a winch, which pulls the kite down and back into the launch gun for subsequent use. The invention also includes an elevated sail assembly comprising (a) a spar-less elevated sail capable of launching from (b) a launching container or the like (c) a pilot kite capable of attachment to the elevated sail (d) means for launching the pilot kite and (e) restraint means capable of attachment to the elevated sail while in the launching container. Elevated sails may also be used to provide aerial platforms to lift equipment for photography, surveying, air pollution monitoring, gas sampling, crop spraying, radar operation or communications. Where loads to be supported exceed a weight of several kilograms the sizes of the kites then required can result in line forces in excess of those readily manhandled. The invention will now be described by way of example only. A ship 1 has a winch system 2 on its deck. Nearby on the deck are located a compressed air driven pilot kite launch gun 3 and a container in the form of an extended hollow cylinder 4. The container 4 is adapted to hold a spar-less kite 5 in the form of a bundle and may be passive or blown by a fan or compressed air. During launch of the elevated sail the elevated sail bundle 5 is positioned in the container 4. Alongside, a pilot kite is positioned in the launch gun 3. A crown line 6 is attached from the pilot kite 7 to the kite bundle 5. The bundle 5 is also attached to the winch system 2 by means of a control line 8. When the sail system is required, the pilot parachute kite 7 is deployed using the compressed air launcher 3 or by direct deployment from the deck. When sufficient pilot line has been paid out to ensure that the pilot kite 7 is pulling its line in a stable manner the line 6 is attached to the upper surface of the elevated sail (figure 1 a). The optimum attachment position varies with the design of sail. For example, an essentially round canopied sail may be pulled from its mid point or crown (figure 1 b) whilst a ram air wing sail may be iifted with a bridle 1 of two or more lines from its top surface (figure 1 c). The elevated sail 5 is released from the container by allowing the restraining winch 2 to pay out. As the sail 5 begins to clear the mouth of the container 4 (figure 1 b) it will begin to inflate due to local air movements around the vessel. This movement from the container and subsequent inflation may be assisted by gas pumped into the container through manifolds 9 or ejected through slots or jets 10 at the container mouth (figure 1 b). With the sail 5 inflated by these means, the control line 8 is paid out until the sail 5 is at the desired height. The pilot kite 7 may be left flying if required or be released from the sail 5 by use of a light trigger line to a snap shackle (or similar) and brought back to the ship (not shown). If the method of launching using gas pumped into the container or jets or slots at the container mouth is carried out with sufficient gas, the elevated sail system may be deployed without any use of pilot kites as the gas jets will counteract the turbulent air flow around the deck of the ship. To recover the sail 5, the restraining winch 2 is used to reel in the flying line 8 so that the shrouds 12 of the sail 5 enter the mouth of the container 4 (which is preferably a smooth fair shape to reduce the possibility of chafing) and the sail is deflated ready for storage until it is required again. The instability sometimes experienced by the sail as it approaches the ship during recovery due to air turbulence may be alleviated by relaunching the pilot kite and attaching it to the crown line of the main kite. Where the towing force due to one sail is insufficient the above methods may be duplicated with a series of containers to deploy sail at intervals either by use of single line or alternatively by the use of separate adjacent lines. Claims

1. A method of launching a spar-less elevated sail comprising the steps of (a) packing the sail into a launching container or the like, the sail being attached to a restraint means (b) connecting the sail to a pilot kite by means of a line (c) the pilot kite being adapted on release to fly and withdraw the spar-less elevated sail from the launching container under control of the restraint means.

2. A method according to claim 1 in which the spar-less elevated sail is recovered'by reverse operation of the restraint means.

3. A method according to claim 1 or claim 2 in which the restraint means is a winch.

4. A method according to any of the preceding claims in which the pilot kite is deployed from a launching gun.

5. A method according to any of the preceding claims in which the spar-less elevated sail is a ram air wing sail or a round canopied sail.

6. A method according to any of the preceding claims in which inflation of the elevated sail on emergence from the launching container is assisted by means of gas jets or the like.

7. A method of launching a spar-less elevated sail as hereinbefore described and with reference to the accompanying drawings.

8. An elevated sail assembly comprising (a) a spar-less elevated sail capable of launching from (b) a launching container or the like (c) a pilot kite capable of attachment to the elevated sail (d) means for launching the pilot kite and (e) restraint means capable of attachment to the elevated sail while in the launching container.

9. An elevated sail assembly according to claim 8 in which the spar-less elevated sail is a ram air wing sail or a round canopied sail.

10. An elevated sail assembly according to claim 8 or claim 9 in which the launching container or the like is a launching gun.

11. An elevated sail assembly according to any one of claims 8 to 10 in which the launching container has gas assisting means for inflating the elevated sails.

12. An elevated sail assembly according to any of the preceding claims in which the means for launching the pilot kite is a launch gun.

13. An elevated sail assembly according to any of the preceding claims in which the restraint means comprises a winch and line.

14. An elevated sail assembly as hereinbefore described and with reference to the accompanying drawings.

15. Vessels whenever fitted with an elevated sail assembly according to any of claims 8 to 14.