Information
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Patent Grant
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6260500
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Patent Number
6,260,500
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Date Filed
Thursday, June 22, 200024 years ago
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Date Issued
Tuesday, July 17, 200123 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
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CPC
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US Classifications
Field of Search
US
- 114 242
- 114 253
- 114 221 R
- 114 51
- 440 33
- 440 34
- 440 40
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International Classifications
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Abstract
A thrust unit having an engine as an external source of motive power for a marine vessel in distress, is delivered by helicopter air drop to a remote seawater location together with other components of the associated towing system, delivered onto the deck of such marine vessel for operational assembly and connection to the thrust unit in order to initiate emergency towing of the marine vessel while immersed in the seawater adjacent thereto under control of personnel on the marine vessel.
Description
The present invention relates generally to seawater towing of marine surface vessels that are in distress.
BACKGROUND OF THE INVENTION
Marine surface vessels in distress during seawater travel sometimes become immobile at some seawater location so as to require an external source of motive power for movement therefrom. The provision of such external motive power source for ship towing purposes, heretofore involved the use of tugboats through which transport of towing apparatus to some seawater location was performed in order to reliably carry out a towing mission on an emergency basis. However, tugboat transport involved substantial transit time following an emergency call from a marine vessel in distress. Accordingly, it is an important object of the present invention to reliably and more quickly perform a towing mission for a ship in distress, involving use of a motive power source externally of the ship at some remote seawater location in response to a distress call from such remote location.
SUMMARY OF THE INVENTION
In accordance with the present invention, components of an emergency ship towing system are selected to perform the towing mission and of a limited weight so as to accommodate safe and rapid transport by helicopter to a remote seawater location at which the towing system components are delivered and operationally assembled by personnel for reliable performance of the towing mission without delay. One of such towing system components, providing the external motive power source, is in the form of a preassmebled thrust unit having a gas turbine type of engine therein, according to one embodiment of the invention, to which a mixture of pressurized air and fuel is supplied through an elongated flexible hose for selective operation of the turbine engine under remote travel speed control. Such thrust unit also includes a rudder and stabilizer assembly through which travel direction and underwater depth control is exercised through elongated signal wiring attached with the flexible hose to an elongated towing cable extending therefrom. The foregoing described type of thrust unit when transported to the required seawater location by the helicopter is dropped through the air for immersion into the seawater adjacent to the ship in distress. The other components of the towing system simultaneously transported by the helicopter to the seawater location, are air dropped onto the deck of the ship in distress for prompt operational assembly thereon by shipboard personnel and attachment to the towing cable, flexible hose and signal wiring extending from the thrust unit immersed in the seawater. On-off control, and selective control over travel speed, direction and underwater depth of the thrust unit during performance of its towing travel operation is thereby effected under control of personnel on the ship through a control box component.
BRIEF DESCRIPTION OF DRAWING
A more complete appreciation of the invention and many of its attendant advantages will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing herein:
FIG. 1
is a simplified side elevation view of a ship undergoing tow by means of a towing system delivered thereto by a helicopter shown hovering above the ship;
FIG. 2
is a partial top plan view of a forward portion of the ship shown in
FIG. 1
, illustrating an assembled arrangement of operational components associated with the towing system;
FIG. 3
is a side view in partial section illustrating the preassembled thrust unit component of the towing system;
FIG. 4
is a block diagram illustrating selective controls associated with the components of the towing system shown in
FIGS. 2 and 3
; and
FIG. 5
is a block diagram schematically summarizing the towing system procedure associated with the embodiment of the invention depicted in FIGS.
1
-
4
.
DETAILED DESCRIPTION OF THE EMBODIMENT
Referring now to the drawing in detail,
FIG. 1
illustrates a marine vessel or ship
10
in under tow at some location in a body of seawater
12
. Hovering above such ship
10
is a helicopter
14
through which components of an emergency towing system are transported upon call to the distressed ship location, and dropped through the air. One of such components, in the form of a towing thrust unit
16
, is delivered by such air drop into the seawater
12
in adjacent relation to the forward portion of the ship
10
as illustrated, while the other emergency towing system components are dropped by the helicopter
14
onto the deck
18
of the ship
10
for assembly thereon by personnel into an arrangement such as that as shown in FIG.
2
. All of the towing system components together weigh approximately 4000 lb so as to be transportable by the helicopter
14
.
The emergency towing system components transported by the helicopter
14
, in addition to the thrust unit
16
, include a flexible towing component
20
connected to and extending from the thrust unit
16
onto the forward end portion of the ship deck
18
. As shown in
FIG. 2
, the towing component
20
has associated therewith a flexible cable
22
hooked at one end by personnel to an anchor windlass
23
for example, and an air hose
24
connected to a compressor and fuel assembly
26
. The flexible towing component
20
also includes control signal wiring
28
extending from the seawater immersed thrust unit
16
to a control box
30
on the ship deck
18
connected to the compressor and fuel assembly
26
for selective on-off control of the thrust unit
16
with respect to ship travel direction and underwater depth by shipboard personnel.
As shown in
FIG. 3
, the thrust unit
16
has an outer hydrodynamically shaped housing
32
enclosing an engine
34
such as a gas turbine connected at its inlet end to the air hose
24
through which air mixed with fuel is fed to the turbine engine
34
for operation thereof under selective control. Water outflow from the turbine engine
34
through the housing
32
is conducted by an exhaust control stop lock
35
. A speed reducer gearbox
36
mechanically connected to the outlet end of the turbine engine
34
transfers power of approximately 1000 hp at a high torque and low rotational speed to an output shaft
38
connected to a propulsor generally referred to by reference numeral
40
. In the illustrated embodiment, the engine driven propulsor
40
includes propeller blades
42
extending radially and rearwardly from a conical shaped rotational hub
44
, surrounded by a stator shroud
46
fixed by struts
48
to the thrust unit housing
32
so as to introduce swirl into the propeller plane. A conventional assembly of rudder
50
and stabilizer
52
are mounted by the shroud
46
in rearward relation to the propulsor
40
, for setting depth and travel direction through servomotors
54
and
56
.
As diagrammed in
FIG. 4
, the servomotors
54
and
56
are respectively under pneumatic control of direction and depth signals supplied thereto by the wiring
28
from the control box
30
. Such depth signals are derived form readings of a depth gage combined with depth command from the control box
30
pursuant to a control scheme such as proportional, proportion a
124
derivative or proportional-derivative-integral to maintain depth by control of stabilizers
52
. The gas turbine
34
, on the other hand, is controlled by the control box
30
through a valve
58
supplying fuel from a fuel source
62
in the assembly
26
to the hose
24
for mixing with pressurized air therein supplied thereto through a valve
60
from an air compressor
64
.
FIG. 5
diagrammatically summarizes the operational procedure associated with the present invention as hereinbefore described. The towing system components are transported for helicopter air drop, as denoted by reference numeral
66
, to the ship distress location
68
. Delivery
70
of one of the towing system components, in the form of the thrust unit
16
, is thereby effected into the seawater
12
adjacent to the distressed ship
10
while the other towing system components connected to the thrust unit
16
by the flexible towing assembly
20
, undergo delivery and operational assembly
72
on the ship deck
18
. Towing
74
of the distressed ship
10
is thereby effected under selective operator control with respect to travel speed, direction and underwater depth through the control box
30
as hereinbefore described.
Obviously, other modifications and variations of the present invention may be possible in light of the foregoing teachings. For example, the gas turbine engine
34
could be replaced by a Diesel engine while the propulsor
40
may be replaced by one employing contra-rotating blades. The elongated cable
20
may be replaced by one without the air hose
24
, connected to a thrust unit in the form of a scharkel. The thrust unit
16
may accordingly be replaced by one having an electric motor with an electromagnetic cable connected to a portable generator on the ship, or by one having limited fuel and air supplies therein. As yet another alternative, the thrust unit which crawls down the side of the ship may be utilized, involving use of electromagnetic tracks and stops on the bottom of the ship hull and magnets to maintain the thrust unit in place while approximately 1000 hp is delivered as motive power for the ship. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.
Claims
- 1. In combination with a system for towing a marine vessel in distress from a seawater location under selected travel speed, direction and underwater depth by means of a thrust unit in the seawater connected by flexible means to the marine vessel and a plurality of other components of the towing system through which control of said selected travel speed and underwater depth are effected from the marine vessel, a method including the steps of: transporting said thrust unit and the other components by helicopter to the seawater location; respectively delivering the thrust unit by helicopter air drop at said location into the seawater and the other components onto the marine vessel; and operationally assembling said other components on the marine vessel for connection by the flexible means to the delivered thrust unit to initiate towing.
- 2. The combination as defined in claim 1, wherein said thrust unit includes an engine through which said control over the selective travel speed is effected, and a rudder/stabilizer assembly through which said selective control over the travel direction and underwater depth is effected.
- 3. The combination as defined in claim 2, wherein said other components delivered by said air drop onto the marine vessel include: a fuel source; an air compressor; valve means respectively supplying fuel from the source and air from the compressor for intermixing and feeding by the flexible means to the engine; and control box means connected to the valve means and the rudder/stabilizer assembly for effecting said selective control over the travel speed, direction and underwater depth.
- 4. The combination as defined in claim 1, wherein said other components delivered by said air drop onto the marine vessel include: a fuel source; an air compressor; valve means respectively supplying fuel from the source and air from the compressor for intermixing and feeding by the flexible means to the thrust unit; and control box means connected to the valve means and the thrust unit for effecting said selective control over the travel speed, direction and underwater depth.
- 5. In combination with a system for towing a marine vessel in distress from a seawater location by means of a thrust unit in the seawater connected to the marine vessel and a plurality of other components of the system through which travel imparted to the marine vessel by the thrust unit is selectively controlled from the marine vessel, a method including the steps of: transporting said thrust unit and the other components by helicopter to said seawater location; delivering the thrust unit and the other components to said seawater location by helicopter air drop; and operationally assembling said other components on the marine vessel after said delivery thereof to initiate towing.
US Referenced Citations (6)