GB2610594A

GB2610594A - Submersible launcher

Info

Publication number: GB2610594A
Application number: GB2112867.3A
Authority: GB
Inventors: Kenneth Burrells Malcolm
Original assignee: BAE Systems PLC
Current assignee: BAE Systems PLC
Priority date: 2021-09-09
Filing date: 2021-09-09
Publication date: 2023-03-15
Also published as: GB202112867D0

Abstract

A launch cradle 100 for a submersible 200 comprises a rigid frame 102, releasable retaining means 106a and 106b for securing a submersible to the underside of the rigid frame, and directing means 110 for urging the submersible down, away from the rigid frame of the launch cradle after the retaining means have been released. The directing means may comprise a spring-loaded pivotal flap, biased to swing away from the launch cradle, an actuated pivotal flap and a motor which rotates the flap about the pivot away from the launch cradle, fluidic jets to urge the submersible away from the launch cradle or an electromagnet adapted to repel a corresponding magnet on the submersible away. A method of launching a submersible from the launch cradle is also disclosed.

Description

SUBMERSIBLE LAUNCHER

FIELD

The present invention relates to methods and apparatus for deploying a maritime submersible vehicle, and in particular to an in-water launch cradle with an improved release mechanism.

BACKGROUND

Maritime submersible vehicles such as mini-submarines, torpedoes, mine counter-measures and other remotely operated underwater vehicles ("ROUVs" or "ROVs") are often launched into water from a larger mother-ship, floating platform or a land-based crane, via a launch cradle. The submersible is lifted from the platform, deck or quay, carried and lowered into the water with the launch cradle, where the submersible is subsequently released to manoeuvre away. However, underwater propulsion is most often provided by means of propeller and it is important that the submersible is suitably distanced from the launch cradle before engaging the propellers to avoid any potential damage to either the launch cradle or the submersible The present invention provides an improved method and device for successfully deploying a submersible craft from a launch cradle.

SUMMARY

According to an aspect of the present invention, there is provided a launch cradle for a submersible. The launch cradle comprises a rigid frame, releasable retaining means for securing a submersible to the underside of the rigid frame, and directing means for urging the submersible down, away from the launch cradle after the retaining means have been released. The submersible may therefore be assisted in clearing the launch cradle before engaging its propulsion system, e.g. propellers.

In one example, the directing means comprises a spring-loaded pivotal flap which is biased to swing away from the launch cradle. This simple solution requires no further electronics or activation, and automatically directs the -2 -submersible down and away from the launch cradle once the retaining means have been released.

In another example, the directing means comprises an actuated pivotal flap and a motor which rotates the flap about the pivot down and away from the launch cradle. In another example still, the directing means employs fluidic jets, for example using air or water, to urge the submersible away from the rigid frame of the launch cradle. In a further example, electromagnets may be used to repel a similar magnetic field present in the submersible. Electromagnets may also be used to retain the submersible to the underside of the launch cradle. Alternatively, mechanically releasable clamps may be used to retain and secure the submersible to the underside of the launch cradle.

In one example, releasable straps may be used to retain the submersible to the underside of the launch cradle. Preferably, the releasable straps may also be retracted, at least partially, once released, so as to further reduce the chance of the straps being caught or tangled in the propulsion system of the submersible.

In one example, the launch cradle also has lifting points for securing the rigid frame to lifting apparatus, allowing the launch cradle to be easily manoeuvred into place in order to successfully deploy the submersible.

There is also disclosed a method of launching a submersible from a launch cradle. The method comprises lowering a launch cradle and attached submersible into the water, releasing retaining means securing the submersible to the underside of the launch cradle, and urging the submersible down, away from the launch cradle after the retaining means have been released, by way of directing means. The submersible is therefore less likely to damage its propulsion system or the launch cradle when activating its propulsion system.

BRIEF DESCRIPTION OF THE FIGURES

Embodiments of the invention will now be described by way of example only with reference to the figures, in which: Figure 1 shows an example of the present invention in a pre-launch configuration; -3 -Figure 2 shows an example of the present invention in a post-launch configuration; and Figure 3 shows a flow chart for an example method of launching a submersible from a launch cradle in accordance with the present invention.

DETAILED DESCRIPTION

Figures 1 and 2 show an example of a launch cradle 100 according to the present invention, and an associated submersible 200. The launch cradle 100 has a rigid frame 102 adapted to provide a convenient easy way to store, transport and deploy the submersible 200. The launch cradle 100 may take many forms ranging from a simple rigid backbone arrangement, to a more cage-like arrangement, which provides more protection to the submersible 200. The example launch cradle 100 shown in Figure 1 has two lifting points 104a 104b for attaching to lifting means 150 (e.g. hooks), so that the launch cradle 100 and associated submersible 200 can be easily lifted, transported and lowered by a crane or other lifting apparatus. The launch cradle 100 may have any number of lifting points 104 so as to be suitable for lifting, transporting and/or lowering into water. Whilst the example in Figures 1 and 2 shows the lifting points 104 as loops for securing hooks to, they could just as easily be replaced by hooks mounted onto the rigid frame 102 to be engaged by corresponding hooks or loops from the lifting means 150. Any suitable means of lift, moving and lowering the launch cradle 100 may be employed the present invention.

The rigid frame 102 also comprises retaining means 106a 106b for securing the submersible 200 to the underside of the rigid frame 102 of the launch cradle 100. The submersible 200 may therefore be lifted, transported and lowered along with the launch cradle 100. In the example shown, the retaining means 106 comprises two strap 106a 106b securing the submersible 200 to the underside of the rigid frame 102. After lifting, transporting and lowering the launch cradle 100 (and submersible 200) into the water, the submersible 200 is deployed from the launch cradle 100 by releasing the retaining straps 106a 106b, thus freeing the submersible 200 from the launch cradle 100. The retaining means 106 may be remotely activated, so that the operators of the launch cradle 100 can release the submersible 200 from the mother ship, platform or quayside. The retaining straps 106a 106b may also be -4 -retractable, at least partially, so as to reduce the chances of the straps interfering or getting tangled with the submersible 200 as it leaves the launch cradle 100. Ideally, the launch cradle 100 is more buoyant than the submersible 200 so that when the submersible 200 is released, the launch cradle 100 remains at or nearby the water's surface even if it is no longer supported by the lifting means 150.

In other examples, the retaining means may comprise adjustable or retractable clamps in order to secure the submersible 200 in place beneath the rigid frame 102. The clamps may be opened in order to release the submersible 200 from the launch cradle 100. In another example, the retaining means 106 comprises at least one electromagnet to secure the submersible 200 to the underside of the rigid frame 102. Once the launch cradle 100 has been safely lowered into the water, the electromagnet maybe switched-off so as to release the submersible 200 from the launch cradle 100. In one example, the submersible 200 has a metallic shell so as to be attracted to the electromagnet when it is switched on. Alternatively, the submersible 200 may also comprise a corresponding magnet (or magnetic field generator such as an electromagnet) opposite to, i.e. attractive to, the electromagnetic retaining means on the launch cradle 100.

In an example wherein the submersible 200 returns to the launch cradle after deployment, e.g. in an exploratory or training capacity, then the retaining means may be re-engaged to secure the submersible 200 to the rigid frame 102 of the launch cradle 100. For example, this could be achieved by manoeuvring the submersible 200 within the confines of the launch cradle 100 (being careful not to damage the propulsion system or the launch cradle) and closing the retractable clamps, or switching the electromagnet back on to attract the submersible 200 to the rigid frame 102 and secure it in place.

The majority of underwater vehicles, i.e. submersibles, utilise at least one propeller to manoeuvre. The propeller(s) may be located at one end of the submersible (as found on a traditional torpedo) or on articulated arms along the length of the submersible body. Once the submersible has been released from the launch cradle, it is important that the submersible 200 does not activate its propulsion means until is at a safe distance from the rigid frame and retaining -5 -means of the launch cradle so as not to tangled and for damage the submersible or the launch cradle 100.

Despite being released from the retaining means, the submersible may find itself still within the confines of the launch cradle, i.e. too close to activate its own propulsion means. For example, in water with a high salt concentration, the submersible 200 may be more buoyant and remain in position under the launch cradle 100.

In order to successfully deploy the submersible 200 from the launch cradle 100 after the retaining means have been released, the launch cradle 100 also comprises a directing means 110 adapted to urge the submersible 200 down and away from the launch cradle 100. In the example shown in Figures 1 and 2, the directing means 110 comprises a pivotal flap or paddle located towards the end of the launch cradle nearest 100 the front of the submersible 200. When the flap or paddle 110 is rotated, the submersible is rotated so as to face down in the water, and when the propulsion manes is engaged, the submersible 200 distances itself faster from the launch cradle 100. Preferably, beyond just rotating the submersible 200 downwards, the flap or paddle 110 pushes the whole of the submersible 200 down away from the launch cradle 100.

In one example, the pivotal flap 110 may be spring-loaded, and biased to an "open" or "downward" position, i.e. away from the rigid frame 102 of the launch cradle 100. When the retaining means 106a 106b are released, the spring-loaded flap 110 pushes the submersible 200 down and away from the launch cradle 100. In another example, the directing means may be actuated, i.e. mechanically driven by a motor, and adapted to operate after the retaining means 106 have been released.

Whilst the example shown displays the directing means 110 as a pivotal flap or paddle, the submersible 200 may also be urged down and away from the launch cradle 100 by other means, for example by at least one spring-loaded or mechanically actuated piston, or fluidic jets for example of water or air. In the example above whereby the submersible 200 also comprises a magnet (or magnetic field generator) then the directing means 110 may also be realised via a similarly poled magnet (or magnetic field) from the launch cradle 100. In one example, both the retaining means 106 and the directing means 110 are -6 -combined into a single magnet, whereby the magnetic field can be switched from a first mode where it attracts the magnetic field of the submersible 200, thereby retaining it to the underside of the rigid frame 102, and a second mode, where the similar magnetic poles repel each other, and the submersible 200 is urged down and away from the launch cradle 100.

In the example shown in Figure 1, the launch cradle 100 is in a prelaunch configuration, wherein the submersible 200 is secured to the underside of the rigid frame 102 by retaining straps 106a 106b and the pivotal flap 110 is in an upwards position, aligned with the body of the submersible 200 beneath it.

Figure 2 shows the launch cradle 100 in a post-launch configuration, just after deploying the submersible 200. The retaining straps 106a 106b have been released (and partially retracted) and the submersible 200 has been urged downwards and away from the launch cradle 100 by the pivotal flap 110. The submersible 200 is then safe to engage its propulsion means manoeuvring away from the launch cradle 100.

Figure 3 shows a flow chart for an improved method 300 of launching a submersible from a launch cradle in accordance with the device described above. The method 300 comprising the steps of lowering 310 a launch cradle and attached submersible into the water, releasing 320 the retaining means securing the submersible to the underside of the launch cradle; and urging 330 the submersible down, away from the launch cradle after the retaining means have been released, by way of directing means.

In a further example, the method includes the step of activating the propulsion means of the submersible only once it is at a pre-determined safe distance from the rigid frame and retaining means of the launch cradle, so as not to tangle and /or damage the submersible or the launch cradle 100. This distance will depend on the submersible propulsion means (i.e. whether they employ traditional rear propellers, or articulated arm propellers) and/or the launch cradle configuration (e.g. a simple rigid backbone or a cage-like enclosure).

Any references herein to directional and positional descriptions such as, top, bottom, upper, lower, proximal, distal, inside, outside, rear, and directions are to be interpreted by the skilled reader in the context of the examples described to refer to the orientation of features shown in the drawings, and are -7 -not to be interpreted as limiting the invention to the literal interpretation of the term, but instead should be as understood by the skilled addressee.

Where, in the foregoing description, integers or elements are mentioned that have known, obvious, or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present disclosure, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the disclosure that are described as optional do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, while of possible benefit in some embodiments of the disclosure, may not be desirable, and can therefore be absent, in other embodiments. -8 -

Claims

CLAIMS 2. 3. 4. 5. 6. 7. 9.A launch cradle for a submersible, the launch cradle comprising: a rigid frame; retaining means for releasably securing a submersible to the underside of the rigid frame; and directing means for urging the submersible down, away from the launch cradle after the retaining means have been released.
The launch cradle according to claim 1, wherein the directing means comprises a spring-loaded pivotal flap which is biased to swing away from the launch cradle.
The launch cradle according to claim 1, wherein the directing means comprises an actuated pivotal flap and a motor which rotates the flap about the pivot away from the launch cradle.
The launch cradle according to claim 1, wherein the directing means comprises fluidic jets to urge the submersible away from the launch cradle.
The launch cradle according to claim 1, wherein the directing means comprises an electromagnet adapted to repel a corresponding magnet on the submersible away.
The launch cradle according to any preceding claim wherein the retaining means comprises releasable straps.
The launch cradle according to claim 6 wherein the releasable straps are also retracted once being released.
The launch cradle according to any preceding claim wherein the retaining means comprises electro magnets.
The launch cradle according to any preceding claim wherein the retaining means comprises retractable clamps.
10. The launch cradle according to any preceding claim, comprising lifting points for securing the rigid frame to lifting apparatus.
11. A method of launching a submersible from a launch cradle, the method comprising the steps of: lowering a launch cradle and attached submersible into the water; releasing the retaining means securing the submersible to the underside of the launch cradle; and urging the submersible down, away from the launch cradle after the retaining means have been released, by way of directing means.
12. The method according to claim 11 further comprising only activating the propulsion means of the submersible once it is at a pre-determined distance from the rigid frame and retaining means of the launch cradle.