WO2020151906A1

WO2020151906A1 - Anti-sinking measures for aquatic vessels

Info

Publication number: WO2020151906A1
Application number: PCT/EP2020/000020
Authority: WO
Inventors: Robert Jordan
Original assignee: Robert Jordan
Priority date: 2019-01-24
Filing date: 2020-01-20
Publication date: 2020-07-30
Also published as: GB2584984A; GB201900966D0; DE212020000512U1

Abstract

A vessel is provided with a tailored web of waterproof fabric, stowed in a pouch above the bow and which is deployed upon impact of the hull with floating debris. The web is drawn down below the bow and aftwards by tensioning cables to cover any hole created by the impact so that water pressure urging the web over the hole seals the hole and prevents sinking of the vessel.

Description

ANTI-SINKING MEASURES FOR AQUATIC VESSELS

The present invention relates to measures for preventing aquatic vessels from sinking in the event that they are holed below the waterline. Within the context of this patent specification, the term 'aquatic vessel' is intended to encompass any boat or ship that is capable of offshore sailing. Thus, for example, the term applies to both sailing and motor boats, to commercial ships, passenger ships of all sizes, warships and other naval vessels.

All vessels are vulnerable to sinking if holed below the waterline. To mitigate this risk, larger vessels may be constructed with discrete watertight compartments inside the hull, typically provided by transversely extending bulkheads. A hole in the hull adjacent one compartment would therefore result in water leaking into that compartment only; provided the vessel overall retains sufficient buoyancy sinking can therefore be avoided. This design is not foolproof; RMS Titanic was constructed in this way. Further, such a design may be unsuitable for vessels whose purpose requires deck areas below or in the region of the waterline to be differently configured. For example, roll-on, roll-off ferries require large open deck areas. It is also less suitable for smaller and less expensive vessels.

A first aspect of the present invention provides an apparatus for preventing a vessel from sinking as a result of it being holed in its hull near or below the waterline comprising a web of fabric which is connected to the hull at or in the vicinity of the bow of the vessel, the web being stowed on the vessel during normal operation of the vessel and rapidly deployable to extend rearwards to envelope at least a part of the hull of the vessel and thereby to cover a hole in the hull of the vessel from the outside.

Embodiments of the invention will now be described, by way of example, and with reference to the accompanying drawings, in which:

Fig. 1 is a side view of a sailing boat equipped with an embodiment according to the present invention;

Fig. 2 is side view of the sailing boat of Fig. 1 showing a web according to an embodiment of the present invention fully deployed;

Fig. 3 shows a detail of Fig. 1;

Fig. 4 is a plan view of the detail of Fig. 3;

Fig. 5 shows a web according to an embodiment of the present invention stowed into a pouch;

Fig. 6 shows the detail of Fig. 3 during operation;

Fig. 7 is a side view of the boat during deployment of an embodiment of web according to the present invention; Figs 8 and 9 show the operation of a web on a motor boat;

Figs. 10 and 11 are schematic illustrations of the deployment of an embodiment of web according to the present invention showing the geometrical considerations involved during deployment.

Referring now to Fig. 1, an aquatic vessel, here having the form of a sailing boat 10 is illustrated at rest in the water. The hull 20 of the boat 10 is partly submerged below the waterline W. The depth of submersion of the hull 20 is known as the draft D. The vertical projection of the hull 20 above the waterline W is known as the freeboard F. The upperdeck 30 of the boat is enclosed by upright stanchions 32 interconnected with one or more grabrails 34. The part of the upperdeck 30 directly above the bow 40 is often referred to as the forward pulpit or bow pulpit 42. The stanchions 32 in this region often extend higher than those elsewhere. In addition or alternatively, the stanchions 32 in this region are often are angled forwards as in the present embodiment. Because they serve to prevent sailors from falling into the water and also as a tether point for various safety equipment, the stanchions 32 are both strong and well-fastened to the boat 10.

One of the greatest vulnerabilities to the ongoing seaworthiness of all vessels is the potential for damage to the hull 20 below, or in the region of the waterline W. For example, one way in which damage of this kind is often caused these days is by shipping containers which have been accidentally shed from large ships. Such containers frequently float just below the surface. An impact with, for example, with the corner of such a container can perforate the hull 20. The vessel would then take on large quantities of water through the resultant hole which, in turn, will eventually cause it to sink.

According to embodiments of the present invention, the vessel is equipped with a web of fabric which is stowed during normal operation but, if a hole is created in the hull below or in the region of the waterline W, the web can be rapidly deployed to cover the hull from the outside. Once the web is deployed, the water pressure outside the hull 20 operates to urge the web against the hull and form a seal over the hole and so act to prevent the vessel from taking on water through the hole and permit navigation of the vessel to safety. In order to be effective, the web must be deployable sufficiently quickly to seal the hole before the vessel takes on sufficient water to cause it to sink. The manner and location in which the web is stowed therefore requires the web to be available for rapid deployment. In one embodiment, the web is stowed on and connected to the vessel in the freeboard region of its hull so that it can be drawn aftwards from its connection point or points with the hull and in the direction of flow of water over the hull. Advantageously, therefore, the connection point or points of the web are located in the bow region. The web can be any shape and configuration which enables it to be stored during normal operation and then drawn aftwards over the hull so that it covers the hole created sufficiently quickly to prevent the vessel from sinking. The extent to which the web can be drawn over the hull will depend to an extent upon the configuration of the hull. Thus, in the case of a hull which has a protruding keel, the extent to which the web can be drawn aftwards is limited by the keel. However, even in such circumstances the web will be available to cover a large proportion of the holes that are likely to be accidentally created in the hull. The web 50 is preferably made of a material with low water permeability, though this is not essential since even a web with high water permeability will significantly reduce the flow of water into the hull; and, once deployed, surface tension phenomena may additionally serve to reduce the water permeability of a web that is not intrinsically waterproof. Once such a web has been deployed, the flow of water into the hull will be reduced or, preferably substantially prevented. In either circumstance, water entering the hull can then be pumped out (even where water continues to enter but at a reduced rate, pumping the water out will have a greater effect).

Referring now additionally to Fig. 2, in the present embodiment, a web 50 is constructed so that it has a shape which fits snugly over the hull 20. That is to say that the shape of the web 50 is 'tailored' to replicate, as far as is practically possible, the shape of the hull 20. The web 50 is illustrated in Fig. 2 in its fully-deployed condition and covers a hole H in the hull 20 caused by an impact with floating debris. The web 50 is connected at a plurality of points along its proximal edge to a corresponding number of points on the freeboard of the hull 20 and located in the region of the bow 40. In the present example, the proximal edge P of the web 50 is connected to the boat at the uppermost point on the hull freeboard, that is to say along or adjacent the gunwale 70, using the stanchions 32 as connection points. Two upper lines 80A are connected to the distal edge of the web 50 at the port and starboard sides respectively (self-evidently, only the starboard side edge being shown in Fig. 2). Each of upper lines 80A extends aftwards from its respective (port or starboard) connection point 82 with the distal edge of the web 50 to a tension cable 86. Two lower lines 80B are connected to the distal edge of the web 50 at a common, centre connection point 84 which is substantially coaxial with the keel 200 of the boat. Each of the lower lines 80B extends upwards and aftwards around the hull 20 from the common connection point 84, and is connected at the other end to the respective tensioning cable 86 at common point with the corresponding upper line 80A. Each of the tensioning cables 86 is fastened to the boat by means of a rope clutch 90 located on the upperdeck 30. Such a rope clutch is well known perse (one commercially available example being the Lewmar DC1 rope clutch) and is operable in a retract condition and a release condition. In the retract condition the tensioning cable 86 is retained by a cam on the clutch in such a manner that the cable 86 may be retracted aftwards, thereby to draw the web 50 aftwards around and against the hull; simultaneously, the cam prevents any slippage of the tensioning cable 86 in a forwards direction. Thus when retained in the clutch the cable 86 is capable of being retracted aftwards to assist in the deployment of the web 50 and to secure it in position; but prevents any release of the cable 86 and therefore of the web 50. In the release condition the clutch cam is released and the cable 86 may be moved in either direction, thereby permitting the web 50 to be removed from its deployed condition.

Referring to Figs. 3 to 5, the web 50 is only deployed if and when a boat has been punctured in its hull below or close to the waterline W; the web 50 being stowed ready for rapid deployment the remainder the time. In the present illustrated embodiment, the web 50 is packed within a pouch 60. The present embodiment of pouch 60 is additionally illustrated in plan view and in a partly-opened state in Fig. 5. The pouch 60 is elongate and formed by two elongate fabric panels 62, 64 having mutually-opposing, releasably closable edges 62E, 64E which, in situ, face downwards (i.e. towards the water) and by means of which the web 50 is held releasably within the pouch 60. Releasable, mutual engagement of the edges 62E, 64E is enabled in the present embodiment by means of a known hook and loop closing mechanism (one example of which is provided under the registered trade mark VELCRO). Any configuration for the releasable engagement within the pouch which permit secure stowage and quick deployment may, however, be employed. One example of an alternative configuration is one which is akin to that used in the packing and deployment of a parachute, employing a sequence of releasable individual and typically elastic fastenings.

The elongate pouch 60 is connected to the exterior of the hull freeboard 20, extending beamwards (i.e. from one side of the bow 40 to the other) and symmetrically around the bow 40 (best illustrated in Fig. 4), so that, upon deployment it will extend downwards over the bow 40 below the waterline W, aftwards and substantially simultaneously around both sides of the hull 20. In the present embodiment the pouch 60 is integrated with the web 50, so that the fabric panels 62, 64 are panels which are in effect located on the web in the region of its proximal edge (an analogous arrangement is used for portable raincoats where the raincoat is packed into one of its pockets). The web 50 (and therefore also the pouch 60) is attached to the uppermost region of the hull freeboard; that is to say in the region of the gunwale 70. Attachment of the web 50 and pouch 60 in the present embodiment is made to the stanchions 32 at their base by means of rings 62. Thus in the present embodiment, both the web 50 and pouch are directly fastened at its proximal edge to the boat via the stanchions 32. This configuration may also apply where the pouch 60 and web 50 are distinct entities. In an alternative embodiment in which the web 50 and pouch 60 are distinct, the web 50 may be fastened to the boat by fastening the web 50 to the pouch 60 which is, in turn, fastened to the boat.

Referring again to Fig. 3, the manner in which the web 50 is packed into the pouch 60 is important because it affects the rapidity and ease with which the web 50 may be deployed. In a preferred embodiment the web 50 is packed by successive crushing of small parts of it into the pouch 60. One example of that mode of packing is to concertina the web 50 into the pouch 60. Sailors are familiar with packing in this manner because sails are also stored in this way and it is often referred to it as 'flaking'; this manner of packing of the web 50 is illustrated schematically in Fig. 3.

Manual deployment of the device will now be illustrated with additional reference to Figs. 6 and 7. The tensioning cables 86 are retained within their respective rope clutches 90, accessible to (for example) the helmsman of the boat. In the event of an impact with (for example) floating debris, the helmsman pulls on the cables 86. This has the effect of pulling the web 50 to forces a release of the engagable edges 62E, 64E of the fabric panels 62, 64 with the result that the distal edge of the web 50 then emerges from the pouch 60. Further tension on the cables 86 continues to pull the web 50 dowwards. The downards movement of the distal edge, and thus the continuing emergence of the web 50 from the pouch 60 is further assisted by one or more sink weights 100 attached to the web 50 in the region of its distal edge. Once the distal edge of the web 50 has entered the water the combination of the flow of water aftwards (from the continued forward motion of the boat) and the angle of the bow 40 cause the web 50 first to continue moving downward to the full draft of the hull 20, and then to be pulled aftwards towards its position of full deployment. This action is assisted by the provision of one or more drogue regions or pockets 110 attached to the web 50 near its distal edge, which act to catch the water flowing aft and thereby to pull the web 50 aftwards relative to the boat more strongly as a result.

Referring once again to Figs. 3 and 6, in a modification, the pouch 60 incorporates an inflatable bladder 120, of the kind frequently used in a self-inflating life jacket. The bladder 120 is actuable from the helm (typically by means of an electrical signal in a manner which is known per se) and acts to expel the web 50 from the pouch. The bladder is shown in Fig. 3 in its armed state and in Fig. 6 having been 'fired' to force the web 50 rapidly out of the pouch 60. In further modifications the operation can be further automated. Thus, for example, the rope clutches 90 may comprise motors which are actuable automatically upon firing of the bladder 120 to retract the tensioning cables 86 to a predetermined extent (i.e. a through a predetermined length of retraction) and to a predetermined tension corresponding to full deployment of the web 50 and optimum retaining tension of the cables 86 . In yet a further automated modification, the boat may comprise one or more accelerometers and associated signal conditioning and analysis functionality which, in combination, are adapted to distinguish an impact of the hull 20 with debris from usual sailing conditions (including rough sea sailing conditions where the hull 20 may have relatively high impacts with waves) and, in the event an impact is detected, to fire the bladder 120 so that the entire operation of the device is automated. This has the advantage that the device can be deployed when no helmsman or other operator is present and so is particularly advantageous for boats which are sailed single-handed. In a further modification, a simpler embodiment provides a web which is deployable with a greater degree of intervention by those crewing the vessel. Thus the web 50 comprises one or more catch members which can be engaged by crew, for example stationed on the upperdeck 30, using boat hooks or other such tools to pull the web aftwards.

It has been observed above that movement of water aftwards over the hull 20 assists in the deployment of the web 50. Such movement is not, however, essential in any embodiment. Pitching of the vessel in the waves, even when stationary, can assist in the deployment of the web to envelope the relevant area of the hull 20.

In an alternative embodiment the web 50 may be stowed inboard. For example, the hull 20 may comprise a compartment having the same profile as the elongate pouch 60, i.e. a compartment located within the hull 20 freeboard, extending beamwards and symmetrically around the bow 40. Preferably such a compartment would be located at the uppermost point on the hull freeboard and therefore would extend along the exterior of the gunwale 70. According to such an embodiment the compartment preferably have one or more flaps which open to permit deployment of the web 50 in an emergency but, when closed, are preferably watertight, preferably rendering the compartment invisible or barely perceptible to the eye. Such a design is, self-evidently, one in which a safety device is integrated into the design of the boat whereas the design in which the web is stowed within a pouch 60 enables retrofitting to existing boats.

The present invention has been illustrated by reference to its use on a sailing boat having a fixed keel. Some vessels have a retractable keel (for example those available from Southerly). In a modification, where a vessel has a retractable keel, the web may be deployable in two stages: a first stage being deployment of the web for a hole which is forward of the keel (and so can be deployed to seal the hole as illustrated substantially in Fig. 2 for example); and a second stage in which a further section of the web may be deployed aft of the keel upon retraction of it, where the hole has been created level or aft with the keel.

The present invention may be may be used with any aquatic vessel of any size or purpose. Thus it may be used equally with motor boats used for leisure, military vessels (destroyers, frigates and aircraft carriers) and commercial shipping (such as large container vessels). It has significant utility in connection with mechanically-powered vessels.

Thus, for example, the storage and use of the device on a motor boat is illustrated in Figs. 8 and 9. It will be noticed that the bow angle of the boat in Fig. 8 and 9 is significantly steeper with respect to the waterline W than that of the boat illustrated in Figs. 1 to 7. Self-evidently, the steeper the bow angle, the easier and more rapidly the web 50 may be deployed. The geometry illustrating the forces involved during deployment is illustrated schematically in Figs. 10 and 11. Fig. 10 illustrates in a schematic manner, the direction of a force B applied, via the tensioning cables 86 (and then the upper and lower lines 80A, B) to the distal edge of the web 50 once it is being deployed. As long as the direction of the force P operates to apply tension to the web 50 such that the angle ϋ between B and the edge of the bow (and illustrated in Fig. 11) is greater than 90°, there will be a resultant force on the web 50 which acts to pull it downwards towards the waterline W.

Some vessels have a bow angle which is much more shallow and in some cases which projects forward at the waterline. To ensure reliable deployment of the web 50 with such vessels a number of alternative configurations are possible. In one alternative, the pouch may be located either inboard or outboard at the very forward apex of the bow (and therefore below the waterline). In such an embodiment, preferably two different sets of tensioning cables are provided: one to pull the distal edge of the web aftwards and another to pull a proximal edge of the web upwards above the waterline towards the bow pulpit. It is to be understood that the different features of the invention as described above, are not limited to their association with the embodiments in connection with which they were first described. Unless stated otherwise, all aspects of the invention are generally applicable to all other embodiments of the invention described herein.

Claims

1. Apparatus for preventing a vessel from sinking as a result of it being holed in its hull near or below the waterline comprising a web of fabric which is connected to the hull at or in the vicinity of the bow of the vessel, the web being stowed on the vessel during normal operation of the vessel and rapidly deployable to extend rearwards to envelope at least a part of the hull of the vessel and thereby to cover a hole in the hull of the vessel from the outside.

2. Apparatus according to claim 1 wherein the web has a shape corresponding to the shape of the hull so that, when deployed, the web covers the hull in a tailored manner.

3. Apparatus according to any one of the preceding claims, wherein the web is packed in a pouch ready for deployment.

4. Apparatus according to claim 3 wherein the pouch is elongate, is located in the freeboard region of the hull and extends beamwards, substantially symmetrically around the bow.

5. Apparatus according to any one of the preceding claims wherein, when the web is packed into the pouch, it has a concertina configuration.

6. Apparatus according to any one of claims 3 to 5 wherein the pouch is an integrated part of the web.

7. Apparatus according to any one of claims 3 to 6 5 wherein the pouch is located in the gunwale region of the vessel.

8. Apparatus according to claim 7 wherein the pouch is located inboard of the hull within a correspondingly-shaped recess, closed externally by movable panels which open to permit deployment of the web.

9. Apparatus according to claim 7 wherein the pouch is located outboard of the hull and is retained in place by connection to stanchions extending upwards from the vessel deck.

10. Apparatus according to any one of the preceding claims wherein the web is connected to the vessel along a proximal edge and a distal edge of the web moves over the hull during deployment.

11. Apparatus according to claim 10 wherein the web further comprises weights attached to the web adjacent or in the region of the distal edge of the web, to assist downward movement of the web into and below the water during deployment.

12. Apparatus according to claim 10 or claim 11 wherein the web comprises at least one drogue region adapted to catch water moving aftwards along the hull thereby to assist deployment of the web to envelope the hull.

13. Apparatus according to claim 12 wherein the drogue region is located adjacent to or in the region of the distal edge of the web.

14. Apparatus according to any one of claims 3 to 13 wherein the pouch comprises first and second panels which are releasably mutually enagable along a mutually-opposing edge to permit the distal edge of the web to move out of the pouch.

15. Apparatus according to claim 14 wherein the mutually opposing edges are closable by means of a hook and loop fastening mechanism.

16. Apparatus according to any one of the preceding claims further comprising a cable connected at one end to the web in the region of its distal edge, the other end of the cable being retained aftwards of the pouch.

17. Apparatus according to claim 16 wherein the cable is retained in a rope clutch thereby to enable retraction of the cable during deployment of the web and ongoing tensioning of the cable to retain the web in its operating configuration, the clutch being releasable to enable release of tension in the cable to repack the web.

18. Apparatus according to claim 17 comprising a pair of cables each connected to the distal edge of the web and extending from the distal edge over, respectively, port and starboard sides of the hull to one or more clutches.

19. Apparatus according to any one of the preceding claims wherein the web is made of a fabric of low water permeability.

20. A method of remediating the accidental creation of a hole in the hull of a vessel comprising the steps of: stowing a web of material on the vessel in the region of the bow; and upon detecting an impact with the hull, deploying the web such that it is connected with the vessel in the bow region and extends aftwards from the bow and over the hole such that external water pressure acts to urge the web to seal the hole.

21. A method according to claim 20 further comprising the step of stowing the web in a pouch located at the bow of the vessel.

22. A method according to claim 21 further comprising the step, during stowage, of flaking the web to ensure that it is stowed in a manner permitting its reliable and rapid deployment.

23. A method according to any one of claims 20 to 22 further comprising the step of weighting the web during deployment from the pouch.

24. A method according to any one of claims 20 to 23 further comprising the step of causing the web to drag upon the water during deployment thereby to ensure that forward motion of the vessel through the water causes aftwards movement of the web relative to the hull.

25. Apparatus for preventing a vessel from sinking as substantially described herein and with reference to the accompanying drawings.

26. A method of remediating creation of a hole in the hull of an aquatic vessel as substantially described herein and with reference to the accompanying drawings.