[0001] This invention relates to a marine observatory craft.
[0002] Hitherto marine observatory craft have been useful in relation to the observation
of underwater locations such as coral reefs and also marine life especially of the
type that abounds in sub-tropical and tropical climates. Usually such locutions are
relatively close to mainland resorts and it was necessary to transport tourists from
the mainland to the underwater location of interest whereafter it was essential for
tourists to transfer to small craft having glass bottoms in order to view the underwater
location. The transport craft was normally a motorboat having an inboard or outboard
engine. The use of small glass bottom boats was found to be generally satisfactory
if the weather was fine, the tourists were reasonably young and agile, and the underwater
locations were relatively close to the mainland.
[0003] It therefore will be appreciated that not all of the above conditions for use of
smallglass bottom boats were present on a particular day and thus use of glass bottom
boats was not appropriate.
[0004] It further will be appreciated that the majority of less developed and therefore
more interesting marine areas arc inaccessible to the majority of tourists who are
not scuba divers capable of operating off larger conventional vessels in the inaccessible
or remote underwater locations.
[0005] United Kingdom Specification 2 046 673 to Rambridge describes a partly submersible
boat with a ballast tank or tanks in which water can be passed and viewing windows
which lie partly or wholly below the surface of the water at least when the boat is
partly submerged. The control cabin is located forwardly and on the same level as
the passenger level and thus will always be at least partly submerged in the travelling
mode. The water may be pumped into the ballast tanks or alternatively it may be scooped
while the boat is in motion into the ballast tank(s) via an inclined pipe. While mention
is made in U.K. Specification 2 046 673 of the fact that more than one ballast tank
may be included in each hull there is no specific description of same in the drawings.
Also there is no specific description of how the water may be pumped into or out of
the ballast tanks.
[0006] U.K. Specification 2 046 673 only discloses a displacement hull which must at all
times be located below the waterline when in a travelling mode. This means that the
invention of U.K. Specification 2 046 673 is only applicable to small boats and thus
is not suitable for medium to large charter vessels because the boat of U. K. Specification
2 046 673 may only travel in a ballasted state due to water always being present in
the ballast tank(s). It is also believed that the Rambridge boat in having a control
cabin on the same level as the passengers included in the or each hull will provide
problems in relation to steering and handling as the driver or operator will not be
in an elevated position to thereby provide effective handling control when either
in the submerged mode or the travelling mode.
[0007] The Ram bridge boat also requires the use of stabilizing floats for effective flotation
and thus this provides a boat which is very unconventional in appearance and it is
believed speculative in nature especially when no structural components such as bulkheads
and the like are disclosed.
[0008] It is also noted in regard to the Rambridge boat that the ballast tanks are located
on the bottom portion of each hull or alternatively in a briding portion interposed
between each hull and effectively the ballast cannot be carried in a position approximately
centrally or middle of the height of the boat and it is therefore believed that will
adversely affect submerging operations because the ballast tanks are therefore of
limited storage capacity.
[0009] A further problem with the Ram bridge boat is that each of the passenger viewing
areas are fully enclosed and thus this will be deleterious to passenger comfort because
of the fact that some passengers may experience a claustrophobic feeling when the
boat is in a submerged condition.
[0010] The object of the present invention is to provide a marine observatory craft which
alleviates the abovementioned disadvantages associated with the prior art.
[0011] The marine observatory craft of the invention includes:
one or more planing type hulls; viewing means associated with the or each hull;
one or more transverse bulkheads dividing the or each hull into a plurality of separate
internal compartments which are sealed from each other;
one or more ballast tanks included in each internal compartment which function as
seat supports wherein each internal compartment includes a viewing area having one
or more of said seat supports,
a control superstructure located above said plurality of internal compartments,
means for selectively flooding said ballast tanks whereby the craft may move in
(i) a travelling mode wherein the viewing means is located above the waterline; and
(ii) an observing mode in which the viewing means is located below the waterline;
said flooding means including pump means; valve means controlling flow of water through
the pump means; inlet and outlet; a feed conduit having separate communication conduits
with each ballast tank and venting means associated with the or each ballast tank.
[0012] Suitably the craft is nulti hulled and thus may be in the form of a trimaran or catamaran.
However, this does not preclude the fact that the craft may be mono-hulled if desired.
[0013] Preferably the craft is a catamaran having a pair of hulls separated by a body portion
incorporating the control superstructure and the viewing means is located on each
side of each hull. The craft may be powered by an inboard or outboard engine or engines.
Preferably there is a row of seats provided on each side of each hull.
[0014] The viewing means may comprise an elongate window located in each side of both hulls
but more suitably the viewing means comprises a row of spaced viewing ports in an
associated wall of the or each hull. The viewing means preferably slopes outwardly
and upwardly so as to facilitate viewing of underwater locations directly beneath
the craft.
[0015] Each ballast tank may extend above the waterline when the craft is in the travelling
mode and may communicate with a base reservoir located in each copartment and which
may be flooded before water may enter the ballast tanks.
[0016] The pump means may be of any suitable type. The inlet and outlet may be separate
but more preferably there is provided a conduit that functions both as an inlet and
an outlet.
[0017] A preferred embodiment of the present invention will now be described, by way of
example only, with reference to the accompanying diagrammatic drawings, in which:-
Figure 1 is a sectional view of a marine observatory craft constructed in accordance
with the present invention and taken along the line b-b of Figure 2;
Figure 2 is a sectional view taken along the line a-a of Figure 1;
Figure 3 corresponds to Figure 1 on a smaller scale and showing the craft in an unflooded
state and in the travelling mode;
Figure 4 corresponds to Figure 3 but shows the ballast tanks in a partially flooded
state and thus between the travelling mode and an observing mode;
Figure 5 also corresponds to Figure 3 but shows the ballast tanks in almost fully
flooded state and in an observing mode;
Figures 3A to 5A are sectional views taken along the line c-c of Figures 3 to 5;
Figure 6 is a sectional view of the craft taken along the line e-e of Figure 7 and
showing the ballast tanks fully flooded;
Figure 7 is a half plan view of the craft taken along the line d-d of Figure 6;
Figure 8 is a sectional view of the craft taken along the line g-g of Figure 9 and
showing the flooding means for the ballast tanks;
Figure 9 is a half plan view of the craft taken along the line f-f of Figure 8,
Figure 10 is an enlarged fragmentary view of part of Figure 9 illustrating the method
of operation of flooding; and
Figure 11 is an enlarged fragmentary sectional view along the line h-h of Figure 6.
[0018] In the drawings the marine craft 10 includes a control superstructure 11 and hulls
12. Each hull 12 on each side thereof is provided with a row of seats 13 and a row
of viewing ports 14. Esch port 14 as shown in Figure 2 extends outwardly and upwardly
and is located immediately adjacent to an associated seat 13. There is also provided
bulkheads 15, 16, 17 and 18 as shown. Bulkhead 15 is a collision bulkhead and there
is shown a door 19 communicating between the interior of each hull 12 and the interior
of the front or bow of the craft 10. The cockpit includes windscreen 20.
[0019] As best shown in Figures 8-10 there is a pump 21 which may be of any suitable type
such as a centrifugal pump or gear pump and a network of conduits comprising an inlet-outlet
conduit 22, solenoid valves 23 and 24, conduits 25A, 25B, 26A and 26B and a feed conduit
27 to ballast tanks 28 which form the interior of the hollow seats 13. There is also
shown pump conduits 27A and 27B. Each solenoid valve 23 and 24 operate in unison and
are actuated electronically from a control station (not shown) in the cabin 11. In
Figure 10 the flow of water for flooding is shown by curved arrows in full outline
wherein the water flews sequentially through conduits 25A, 27A, 27B and 26B to the
conduit 27 and for deflcoding or draining of water the flow of water is shown by curved
arrows in dotted outline travelling through conduits 27, 25B, 27A, 27B and 26 to the
conduit 22.
[0020] There are also shown in the drawings base reservoir or bilge tanks 29 into which
water enters when the solenoid valves 23 and 24 are actuated to cause operation of
the pump 21 to draw water into the reservoir tanks 29 through the inlet-outlet conduit
22. In fact the inlet-outlet conduit 22 is open to the sea and is kept permanently
full of water so that the pump 21 is self-priming.
[0021] There are also shown breather pipes 30 which are included in the ballast tanks 28
which communicate with the reservoir tanks 29. The breather pipes are useful in that
they allow for venting of air from each ballast tank 28. The feed conduit 27 may deliver
water as shown in Figures 8-9 through reservoir conduits 31 to the reservoir tanks
29 and subsequently to the ballast tanks 28. There is also shown spring loaded or
pressure relief valves 32 which are associated with each breather pipe 30. The valves
32 are regulated initially in trials before being locked or set in position.
[0022] There is also shown a spring loaded pressure relief valve 33 for the tanks 28 and
29 which may be actuated when the pressure in the tanks exceeds a predetermined safety
level. The bulkheads 15, 16, 17 and 18 together with a partition 34 divide the craft
into upper compartments 34A and lower compartments 34B which are fully sealed from
each other in the event of the hulls being penetrated or holed. There is also shown
a housing 36 for the pump 21 and struts 36 interconnecting the hulls 12.
[0023] In operation of the flooding of the ballast tanks the solenoid valves 23 and 24 are
actuated which actuate the pump 21 to draw water from the conduit 22 into the feeder
conduit 27 as previously described and hence through the conduits 31 to the reservoir
tanks 29 and hence into the ballast tanks 28.
[0024] By operation of the solenoid valves 23 and 24 it will be appreciated that the ballast
tanks may only be partially flooded if required as shown in Figures 4 and 4A. In Figures
3 and 3A the craft 10 is in the travelling mode indicated by the waterline 8 when
the reservoir tanks 29 and ballast tanks 23 are unflooded. From Figures 4 and 4A to
Figures 5 and 5A tanks 28 are progressively flooded and thus the craft 10 has effectively
undergone a downward displacement until achieving the almost fully flooded position
shown in Figures 5 and 5A when the craft 10 is in an observing mode indicated by the
waterline 9 where the location of the ports under the waterline facilitates the viewing
of undersea locations by passengers sitting on the seats 13.
[0025] One of the features of the invention as described above is the building in of the
ballast tanks 28 as a normal part of the seating accommodation in the underwater viewing
area, and in such a manner as to provide effective flood bulkheading of each individual
viewing area 34A so that in the event of holing the craft on a reef or the impacting
of a viewing port against a reef only that individual area 34A will flood without
any further danger to the craft 10.
[0026] The provision of ports having a sloping orientation as shown relative to the sea
surface is useful in that it enables the viewer to obtain a sight of underwater areas
directly under the vessel without the need to provide viewing ports on the hull base
which would otherwise present an undesirable safety hazard in vessels used in reef
areas.
[0027] Figure 11 shows ports 35 located in the partition 34 allowing flow of water from
the reservoir tanks 29 to the ballast tanks 28 in each compartment 34B. Also shown
is a floor portion 37 of partition 34.
[0028] Furthermore the hull shape is contoured both to provide marine stability and to prevent
halation or clouding effect due otherwise to direct sunlight effects upon the glass
water interface which would prevent clear viewing. The craft 10 may include a system
of freely rotatable underwater spotlights for night viewing or by the ships crew from
a master panel.
[0029] In order to allow activities such as underwater feeding of fish by scuba divers or
to provide easy access for tourist scuba divers to the water a hydraulically operated
self contained fold away ladder system may be integrated into the bow interior ir
required.
[0030] The craft 10 is suitably designed with planing hulls utilising engines of the currect
horsepower to provide a cruising speed of at least 15 knots. While a catamaran type
hull is described in the preferred embodiment because it offers maximum viewing areas,
an ability to plane in reasonably heavy seas, a good upper tourist servicing and accommodation
area, and the ability to be easily bulkheaded to conform to Lloyds codes for charter
vessels, along with excellent safety factors in the event of accidental impact with
reef areas, it should be understood that the semi submarine principle for bulk transportation
and combined underwater viewing facilities could be applied to hydrofoils, mono-hulls,
trimaran hulls or similar embodiments designed in such a manner as to take advantage
of the specific technical features and advantages to charter operators and passengers.
While it is intended to cover the building of the craft 10 in marine grade aluminium
it should be understood that it is not intended that the preferred or optional embodiments
shall be limited to this material but could be produced in fibreglass, steel, other
metals, ferro cement, ferralite, plastic or any known and acceptable form of seagoing
vessel construction.
[0031] Figure 11 also shows roof 38 enclosing the control superstructure to form a cabin
39 located above upper compartments 34A of each hull 12. Cabin 39 has seats 40 as
shown and passengers sitting on seats 40 may look into compartment 34A through an
opening.
[0032] As shown in Figure 8 the tops of the breather pipes 30 stop just short of the tops
of ballast tanks 28 to allow displaced air to flow downwardly into the reservoir or
bilge tanks 29. Thus the valves 33 in the transoms of the craft 10 will be operable
upon attainment of a pressure in excess of the recommended safety level.
[0033] Figure 10 also shows conduits 42, 43, 46 and 47 which provide for lateral jets of
water to be exited from the craft 10 when in a submerged mode for lateral or sideways
movement when required. The forward conduit 42 exits through an outlet port 49 and
the rear conduit 43 exits through an outlet port 48 shown in Figure 1. Thus the conduits
46 and 47 provide for jets of water to exit outwardly of each hull 12 and the conduits
42 and 43 provide for jets of water to exit inwardly from each hull 12. The conduits
42 and 43' are optional and may be dispensed with if required. Movement of water through
the conduits 42, 43 , 46 and 47 may be controlled by valves 44 and 45 when water flows
through the conduits 27A and 27B as shown.
[0034] The present invention by being limited to planing type hulls thus provides a vessel
of medium to large size for use as a charter vessel and thus in the cruising mode
may travel in an unballasted condition which is contrary to the prior art described
previously. This also provides an extremely fast craft which is quickly semi-submerged
as described previously when required.
[0035] Also by providing a cockpit or control cabin superstruture 11 above the hulls 12
this enables passengers in compartments 34A to sit in a fully open situation without
obtaining any closed in or claustrophobic feeling as would be the case with a fully
enclosed compartment or capsule. This also provides a craft which may be readily handled
or controlled when required and provides a high observation point for passengers when
required.
[0036] The term "planing type hull" as used herein means hulls which may rise above their
normal stationary waterline under the influence of power. Thus in this manner the
wetted surface of the or each hull is reduced in a travelling mode.
[0037] Another advantage of the craft of the invention is that provision is made for lateral
movement when required especially when in an observing mode.
[0038] It should also be noted that flooding or ballasting operations may be controlled
automatically if desired by levelling sensors of any suitable type such as electronic,
mechanical, electrical, hydraulic or gyroscopic sensors. The senors may actuate operation
of the valves as previously discussed which may be gate valves but are more suitably
rotary valves.
1. A marine observatory craft (10) for viewing of underwater locations including:
one or more planing type hulls (12); viewing means (14) associated with the or each
hull;
one or more transverse bulkheads (15 to 18) dividing the or each hull into a plurality
of separate internal compartments (34A, 34B) which are sealed from each other;
one or more ballast tanks (28) included in each internal compartment which function
as supports for seats (13) with each of the seat supports associated with the viewing
means;
a control superstructure (11) located above said plurality of internal compartments;
means (21 to 27) for selectively flooding said ballast tanks (28) whereby the craft
may move in
(i) a travelling mode wherein the viewing means (14) is located above the waterline
(8); and
(ii) an observing mode in which the viewing means (14) is located below the waterline
(9); said flooding means including pump means (21); valve means (23, 24) controlling
flow of water through the pump means; inlet and outlet (22);
a feed conduit (27) having separate communication conduits with each ballast tank
(28) and venting means (30) associated with the or each ballast tank.
2. A marine observatory craft as claimed in Claim 1, wherein said craft (10) is a
catamaran having a pair of hulls (12) separated by a body portion incorporating the
control superstructure (11), and the viewing means (14) is located on each side of
each hull.
3. A marine observatory craft as claimed in Claim 1 or Claim 2, wherein the viewing
means (14) comprises a row of spaced viewing ports in an associated wall of the or
each hull.
4. A marine observatory craft as claimed in any preceding Claim wherein, the viewing
means (14) is sloped outwardly and upwardly so as to facilitate viewing of underwater
locations directly beneath the craft.
5. A marine observatory craft as claimed in any preceding Claim, wherein each compartment
(24B) also includes a base reservoir tank (29) which communicates with the or each
ballast tank (28) so as to be flooded before water may enter the ballast tank.
6. A marine observatory craft as claimed in any preceding Claim, wherein the valve
means includes first and second valves (23, 24) arranged to operate in unison whereby
upon flooding of the ballast tanks (28) water passes through the first valve (23),
then through the pump means (21) and subsequently through the second valve (24) to
the feed conduit (27), and upon draining of the ballast tanks (28) water flows through
the feed conduit (27) to the first valve (23), then through the pump means (21) to
the second valve (24) and thence to an inlet-outlet conduit (22).