Page 48 - NAVAL FORCES 03/2017
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Expeditionary Warfare
effect of sill depth on availability in a seaway. options should always be available, the team Mission Ease and Solus
recommended.
A greater sill depth makes the ramp usable
Features more of the time, but can increase the ship’s govern ments are working up a variety of inno- innovative L&R, having revealed its Mission
Against this background, industry and
The company has recent experience with
hydrodynamic drag.
Clearances around the vehicle are critical
Ease concept in summer 2015. The system in-
vative concepts. On 20 October 2016, for
for the safety of boat crews, with space over-
manned maritime system (UMS) developer
head to allow for relative motions of boat and example, L&R specialist Vestdavit and un- tegrates hydraulically- or electrically-powered
equipment into a mission bay, enabling L&R
ship, while side clearance must be balanced ECA revealed their agreement to cooperate from both sides. It combines storage cradles
against the need to limit lateral motion. Here, on the next generation of L&R systems for that move fore and aft and transfer cradles
adjustable side fenders are useful if the ship UMS, including remotely operated vehicles, that move laterally to deliver their payloads
must handle different vehicles. Water man- auto nomous underwater vessels and USVs. to telescopic cranes with a choice of single or
agement measures such as wave damping and The idea is to develop complete management dual point lifting systems, the latter of which
water dissipation are proven ways of making systems that enable ships to store, handle on can also handle standard 20ft containers in
operations in higher sea states safer. Boat cap- board, service and recharge the unmanned sys- harbour.
ture can be manual or automatic, but manual tems. The company also worked with H. Hen-
riksen to develop the related Solus integrated
lifting hook/painter hook system designed for
Henriksen Hooks - Used Wherever Reliability Comes First
recovering USVs and other boats in combina-
tion with davits.
Swedish Navy recovers an For recovery, the USV positions itself along-
RIB using a Henriksen single side the ship. The SOLUS telescopic arm lifts
point off load hook.
(Photo: Henriksen) the USV’s handling ropes to the retrieval posi-
tion, then the operator grabs the ropes with a
hook on a pole, allowing the painter rope to at-
tach to the painter line – the painter is perma-
nently strung between a forward boom and the
davit – and the lifting rope to the davit wire,
at which point the USV/boat is lifted aboard.
A-Frame for
DeviceSeas Concept
New stern launch systems are also on offer.
On 19 October last year, for example, STX
France unveiled its DeviceSeas multi-role UV
support ship concept, developed in coopera-
There is a specialism in marine technology for which many seafarers can be grateful when tion with the French Navy and marine research
ever their boat is being launched or recovered. H. Henriksen of Tønsberg in Norway has b een institutes. The 4,000t ship has a large modular
specialising in the design and manufacture of offload boat lifting hooks since 1982. The
company is now recognised as the world leader in this technical niche and jealously guards work deck with an innovative L&R system
its 100% safety record. comprising an A-frame and a rail-guided ve-
Any lifting hook system must be ergonomically efficient and very reliable and this is never hicle handling system.
more important than when used on combat vessels. Henriksen Hooks is consequently proud
of being the principal supplier to the UK’s Royal Navy which appreciates the seamanship and
safety benefits that its single point, offload lifting hooks provide. Soft Rail Trawls for Success
When boats must be deployed quickly, as with fast rescue craft, a single hook mounted at
the boat’s centre of gravity has been found to be the most efficient method. It can be set to While the DeviceSeas design is dominated
open automatically as soon as the boat is on the water and the weight comes off the crane’s by its work deck and L&R system, CTA con-
lifting cable. This ensures a swift, seamanlike separation of the craft from the mother vessel tinues development of its Soft Rail system that
with minimal crew involvement. On its return, a crew member simply catches the crane’s
lifting ring and snaps it into the boat’s hook for recovery to begin. employs a net drogue akin to a fishing trawl
The alternative method still favoured by some navies, requires the boat’s crew to connect to put sufficient tension on two polyethylene
four lifting slings on the boat to a hook from the crane. This is significantly more dangerous, cables that then serve as rails. A steel de-
especially during boat recovery when the operator must catch a heavy hook while simul pressor wing positions the drogue in smooth
taneously lifting the slings to make the connection. Operators are also without a free hand
with which to holdon and can easily injure their fingers or be hit by the hook. Equally signi water clear of surface turbulence and the ship’s
ficant for modern warship design is that the high pyramid of slings created above the boat propeller wash. The vehicle to be launched is
demands considerable clearance during lifting and storage. Instead, by attaching the cable supported on a cradle that slides down the
directly to a hook in the boat, it can be deployed by a beam crane and stowed in compart cables and into the water where it is released.
ments with minimal headroom between the decks. In larger craft, the same hooks can be
fitted fore and aft to create a Henriksen twin system that ensures their simultaneous release. Recovery is essentially the reverse of this.
For customers committed to the use of lifting slings, Henriksen also manufactures an off Manned RHIBs have been launched and re-
load crane hook that transfers some of the safety advantages of its onboard hooks to the covered with the test ship moving at 12kts, and
crane’s hook. This provides automatic offload release but cannot offer the spacesaving the company says that speeds of 20kts or more
benefits of the onboard hook. are possible. SoftRail is simple and compact
Henriksen hooks are manufactured in a range of lifting capacities with design features
such as a swivel mounting to accommodate sideways stresses in rough conditions. Other enough to retrofit to a wide range of ships and
pro ducts include painter hooks linked to the main lifting hook. These ensure that a boat boats and the company is even working on a
cannot be released accidentally and dangerously pulled away from the mother ship during smaller version that would enable a RHIB or
launching. Henriksen also manufactures a capture claw that enables RIBs and fast craft to
be launched and automatically made fast when deployed from the stern ramp of a mother a USV to recover a UUV. The kinds of smart
ship. Despite their variety, all Henriksen hooks are trusted for the practical design and fault thinking embodied in these new systems
less craftsmanship that comes as standard. shows that technological advances involve
more than microchips. NAFO
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