US20090038530A1

US20090038530A1 - Watercraft drogue system

Info

Publication number: US20090038530A1
Application number: US12/221,713
Authority: US
Inventors: Thieu Truong; Robert Lee Cardenas; Loren Hazard Howard
Original assignee: Foster Miller Inc
Current assignee: Vencore Services and Solutions Inc
Priority date: 2007-08-08
Filing date: 2008-08-06
Publication date: 2009-02-12
Also published as: WO2009020602A2; WO2009020602A3; GB2464062A; GB201001962D0

Abstract

A watercraft drogue system including a line deployable in the water to be intercepted by the lower unit of the watercraft's engine, at least a first drogue on one end of the line, a length of stretchable line adjacent the drogue, and at least a first length of slack line secured by a frangible tie. The frangible tie of the watercraft drogue system is designed to break when the drogue is deployed. The length of stretchable line of the drogue system expands in length in order to reduce the tension in the line to prevent kick up of the lower unit of the watercraft's engine and thus arrest the watercraft.

Description

RELATED APPLICATIONS

This application hereby claims the benefit of and priority to U.S. Provisional Application Ser. No. 60/963,972, filed on Aug. 8, 2007, which is herein incorporated by reference.

FIELD OF THE INVENTION

This subject invention relates to non-lethal watercraft arresting systems.

BACKGROUND OF THE INVENTION

Various non-lethal devices have been devised to arrest watercraft. One concept involves using a drogue chute to slow a vessel. See the Report by the U.S. Coast Guard entitled “Non-Lethal Weapons in Law Enforcement Operations,” date and author unknown, incorporated herein by this reference. Propeller entanglement systems are also known. See Id.
Many watercraft, especially those with outboard motors, have a lower unit designed to kick up when an object is struck by the lower unit. See, e.g., U.S. Pat. No. 5,151,058 incorporated herein by this reference. Thus, when the lower unit of a high speed watercraft strikes a drogue chute line and the drogue chute deploys, the tension in the line may cause the lower unit to kick up over the line defeating the arresting capability of the drogue chute concept.
U.S. Pat. Nos. 4,768,417; 5,069,109; 6,325,015; and Application No. 2005/0016372 are also incorporated herein by this reference.

BRIEF SUMMARY OF THE INVENTION

In accordance with the subject invention, the watercraft's lower unit does not kick up when it strikes the drogue chute line because the tension on the line is automatically lowered at the point in time when the drogue chute deploys and then increased in a controlled manner to slow the watercraft off plane. The drogue chute system can be deployed into the water in the path of a watercraft by a launcher (see the Coast Guard Report cited above), by the deployment system of U.S. patent application Ser. No. 11/363,231 incorporated herein by this reference, or by other means known to those skilled in the art.
This invention features a watercraft drogue system comprising a line deployable in the water to be intercepted by the lower unit of the watercraft's engine. The drogue system includes at least a first drogue on one end of the line, a length of stretchable line adjacent to the drogue, and at least a first length of slack line secured by a frangible tie configured to break when the drogue is deployed. The length of stretchable line expands in length to reduce the tension in the line to prevent kick up of the lower unit of the engine and thus arrest the watercraft. The watercraft drogue system may include a second drogue on the other end of the line and multiple lengths of slack line each secured by a frangible tie on each end of the line.
One watercraft drogue system in accordance with the subject invention features a line deployable in the water to be intercepted by the lower unit of the watercraft's engine, a drogue on one end of the line imparting a first force on the line when deployed, and an entanglement payload on the other end of the line imparting a second, lesser force on the line. In this embodiment, the drogue, when deployed, causes the line to urge the entanglement payload into contact with the lower unit of the watercraft's engine to arrest the watercraft.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Other objects, features and advantages will occur to those skilled in the art from the following description of a preferred embodiment and the accompanying drawings, in which:

FIG. 1A is a schematic top view showing a watercraft just before it intercepts one embodiment of a drogue chute system in accordance with the subject invention;

FIG. 1B is a schematic showing a watercraft lower unit engaging the drogue chute line of FIG. 1A;

FIG. 1C is a schematic showing how when the watercraft stretches the line taught and the drogues deploy, the retarding force reaches a level where a frangible ties of the first set of slack lines break;

FIG. 1D is a schematic showing the watercraft now at a lower speed where it continues to pull on the line and causes a tension force sufficient to break a second set of frangible ties;

FIG. 1E is a schematic showing how the retarding force is reapplied when the forward movement of the vessel re-tensions the line; and

FIG. 2 is a schematic showing another embodiment of a watercraft drogue system in accordance with the subject invention.

DETAILED DESCRIPTION OF THE INVENTION

Aside from the preferred embodiment or embodiments disclosed below, this invention is capable of other embodiments and of being practiced or being carried out in various ways. Thus, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. If only one embodiment is described herein, the claims hereof are not to be limited to that embodiment. Moreover, the claims hereof are not to be read restrictively unless there is clear and convincing evidence manifesting a certain exclusion, restriction, or disclaimer.
In one preferred embodiment, watercraft drogue system 10, FIG. 1A includes drogue line 12 deployable in the water in the path of watercraft 14. Drogues 16 a and 16 b are attached to the ends of line 12. Adjacent drogue 16 a is a length of stretchable line 18 a (bungee cord-like in construction) and lengths 20 a and 20 b of slack line secured by frangible ties 22 a and 22 b, respectively. Adjacent drogue 16 b is a length of stretchable line 18 b and lengths 20 c and 20 d of slack line secured by frangible ties 22 c and 22 d, respectively.
As shown in FIGS. 1B-1E, when the outboard motor of watercraft 14, FIG. 1B engages line 12 F_Tis the tension of the line caused by the watercraft pulling on the deployed drogues 16 a and 16 b. F_Bis the tension required to break ties 22 a-d. F_Sis the tension pulling on the stretchable line 18 which is equal to the spring force of the line times the stretch in the line F_S=KX. This allows the stopping force to be applied to the speeding watercraft over a distance X (not shown). X is the distance the line stretches when the watercraft engages line 12. F_Tis equal to F_Swhen the stretchable line is not fully taught.
In FIG. 1C, as watercraft 14 stretches lines 18 a and 18 b taught, the retarding force reaches the force needed to break the first set of ties 22 b and 22 c. This is when F_Tis greater than or equal to F_B1. When this occurs, ties 22 b and 22 c will break releasing an unstressed length of line 20 b and 20 c. This unstressed length of line drops the tension in entire line 12 down to zero which resets stretchable line's 18 a and 18 b spring line feature. As the watercraft 14 continues to translate forward, the tension in lines 18 a and 18 b is reestablished. Typically, F_B1is less than F_B2; F_Sis much less than F_B1; and F_Sis much less than F_B2.
In FIG. 1D, the watercraft speed is at a level where it continues to pull on the line and causes the tension force to reach F_B2and the process described with respect to FIG. 1C is repeated. In FIG. 1E, when the break-away ties snap, F_Tis greater than or equal to F_B2and the untensioned line will be released allowing stretched spring lines 18 a and 18 b to reset (return to untensioned state). Retarding force is reapplied when forward movement of the watercraft re-tensions the line.
Over a couple of cycles of the steps shown in FIGS. 1A-1E, the speed of watercraft 14 will be reduced to a level where its motor is working just to pull the deployed drogues. This will be the equivalent to starting watercraft from a stand still and dragging the two deployed drogues to move. The estimated speed of the watercraft after it is taken off plane in this manner would be less than 10 knots. The result is that the target watercraft will be slowed to a speed suitable for intercepting and/or boarding by a pursuing vessel.
One purpose of the invention is to serve as a non-lethal method to hinder or stop the forward progress of high speed watercraft. One objective is to bring a high speed outboard powered watercraft down off-plane by engaging the line around the outboard's lower unit. Once the watercraft begins to drag the line the invention produces a steadily increasing drag load that slows the watercraft and brings the watercraft off-plane.
The ability to stop or hinder the forward progress of speeding watercraft is a problem that the US Coast Guard faces on a regular basis. This need arises in situations such as capture of drug traffickers along the U.S. coastline, stoppage of watercraft for border security, and/or stoppage or deceleration of run away watercraft to regain control.
The invention is a deployable device that effectively stops high speed watercraft without injuring the occupants. This need for a non-lethal watercraft entanglement system is addressed by this invention.
The subject line and drogue system is capable of engaging and applying a steadily increasing drag force to decelerate speeding watercraft. This system is designed to be deployed in front of the watercraft. Once the watercraft crosses over the line, the lower unit of the outboard engine will engage the line causing the drogues (one at each end of the line) to deploy. The deployed drogues apply tension to the line which pulls at the lower unit of the outboard engine in the opposite direction of the moving watercraft to take the watercraft down from its plane on the water.
It has been demonstrated that the use of a line and drogue system alone will not effectively stop or slow watercraft due to the ability of outboard engines to lift up and skip over impediments. This is a built in safety feature of outboard engines to protect the watercraft and its outboard engine in the event that the lower unit hits an object that exerts a significant load. This safety feature makes it difficult for a drogue and line system alone to stop the watercraft because the stoppage force of the drogue can easily exceed the lift-up force of the outboard engine. Since the magnitude of this force increases exponentially with increasing velocity, higher speed watercraft produce greater stoppage forces from the drogue which increases the chance of engine lift-up. The end result is that the outboard engine will skip over the line completely and the watercraft will be free to continue on its path.
The inventive line and drogue system is designed to dampen and distribute the full stoppage force of a drogue over an increment of time and distance. With this invention, the stopping power generated by the drogue during watercraft engagement is gradually transmitted to the watercraft. As the drag force to the watercraft gradually increases, the watercraft will decrease in velocity, which in turn decreases the load generated by the drogue. There will be a point where the watercraft directly pulls on the drogue but the velocity of the watercraft would be decreased to a point where the drogue applies a drag force sufficient to hinder the acceleration of the watercraft but not enough to kick up the outboard engine. As a result, the watercraft will be slowed significantly as it drags the drogue through the water.
One novel feature of this invention is the ability to gradually introduce the drag force of the drogue to the speeding watercraft. This feature is critical to maintain engagement of the line and drogue system to the lower unit of the engine which leads to the deceleration of the watercraft. The ability to gradually introduce the drag force overcomes the built in safety feature of most outboards (engine lift-up), hence maintaining engagement between the watercraft and effector, where the effector is the drogue system.
Another embodiment of this invention uses the ability of this invention to maintain engagement between the effector and watercraft where the effector features drogues with differential drag forces. This causes the drogue with the lower drag force to be pulled towards the lower unit. This feature provides the means to introduce an entanglement or engine disabling device to the outboard.
In another embodiment as shown in FIG. 2, watercraft drogue system includes line 12′ deployable in the water to be intercepted by the lower unit of an engine of a watercraft 14, drogue 16 b on one end of the line imparting a first force on the line when deployed and an entanglement payload on the other end of the line imparting a second, lesser force on the line so that drogue 16 b, when deployed, causes the line 12′ to urge the entanglement payload 30 into contact with the lower unit of the engine of the watercraft to arrest the watercraft. Typically, entanglement payload 30 is a net which entangles the propeller of the lower unit of the engine. See the Coast Guard Report cited above. Other entanglement payloads are known to those skilled in the art.
Although specific features of the invention are shown in some drawings and not in others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention. The words “including,” “comprising,” “having,” and “with” as used herein are to be interpreted broadly and comprehensively and are not limited to any physical interconnection. Moreover, any embodiments disclosed in the subject application are not to be taken as the only possible embodiments. Other embodiments will occur to those skilled in the art and are within the following claims.
In addition, any amendment presented during the prosecution of the patent application for this patent is not a disclaimer of any claim element presented in the application as filed: those skilled in the art cannot reasonably be expected to draft a claim that would literally encompass all possible equivalents, many equivalents will be unforeseeable at the time of the amendment and are beyond a fair interpretation of what is to be surrendered (if anything), the rationale underlying the amendment may bear no more than a tangential relation to many equivalents, and/or there are many other reasons the applicant can not be expected to describe certain insubstantial substitutes for any claim element amended.

Claims

1. A watercraft drogue system comprising:

a line deployable in the water to be intercepted by the lower unit of the watercraft engine;

at least a first drogue on one end of the line;

a length of stretchable line adjacent to the drogue; and

at least a first length of slack line secured by a frangible tie configured to break when the drogue is deployed and the length of stretchable line expands in length to reduce the tension in the line to prevent kick up of the lower unit and thus arrest the watercraft.

2. The system of claim 1 in which there is a second drogue on the other end of the line.

3. The system of claim 2 in which there are two lengths of slack line each secured by a frangible tie on each end of the line.

4. A watercraft drogue system comprising:

a line deployable in the water to be intercepted by the lower unit of the watercraft's engine;

a drogue on one end of the line imparting a first force on the line when deployed; and

an entanglement payload on the other end of the line imparting a second, lesser force on the line so the drogue, when deployed causes the line to urge the entanglement payload into contact with the lower unit of the engine of the watercraft to arrest the watercraft.