top of page
iainmacneil

09/03/2021 Introducing Astra’s new RIBs


Artist’s impression of ASTRA fitted with 2x Ribcraft custom designed RIBs


On an expedition vessel you can’t have enough RIBs (Rigid Inflatable Boats), tenders, landing craft and jolly boats. One of the notable additions to Astra during her 2021 refit will be 2 purpose built RIBs intended to fulfil different roles.


When our friends at West Coast Marine Services in Troon learned of the requirement to fit twin outboards on a 5.3m RIB, they suggested that we have a close look at Ribcraft, as they would have the necessary creativity and capability to build not one, but two non-standard RIBs to meet Astra’s exacting requirements.


So, what were Astra’s requirements?



Forward (Tender) RIB 4.2m ‘MARMITE 1’




MARMITE 1, Ribcraft 4.2m (Reproduced with permission: Ribcraft UK)

The forward RIB stowage position on Astra comfortably fits a 4.2m RIB, which is a good size for a tender and is not too big for getting in to the smaller tender pontoons on the West Coast of Scotland. This RIB is designed with two saddle seats, comfortable spacing for four passengers to shore and a 50HP Suzuki outboard. As Astra’s forward crane is rated at 1 tonne we wanted a RIB that it could easily lift, particularly if the weather sets in and you are lifting in winds of Force 4 and in seas of a moderate chop. Creation of a 4.2m RIB at 400kg very much met our requirements


For ocean crossings, the ability to switch ‘MARMITE 1’ from its forward position to being stowed at height above the poop deck was also required, beside ‘MARMITE 2’.



Rendering of MARMITE 1, Ribcraft 4.2m

(Reproduced with permission: Ribcraft UK)

Explorer RIB 5.3m ‘MARMITE 2’




MARMITE 2, Ribcraft 5.3m (Reproduced with permission: Ribcraft UK)

The design requirements given to Ribcraft for a larger explorer RIB included twin outboard engines with separate and completely independent fuel supplies to each engine. This RIB needs to be able to comfortably explore 40-50 miles away from Astra and have sufficient fuel for the return journey! With such expeditions envisaged for this RIB, it also requires a digital charting system and an AIS transponder.


The maximum length of RIB that can be comfortably stowed in a cradle mounted above head height on the poop deck, without it extending beyond the aft end of ASTRA is 5.3m.

Within this constraint, the largest pair of outboards that can be fitted is a pair of 2 x 30HP Suzuki outboards.

This RIB is fitted with 4 x wing back seats for added ‘comfort’ on longer journeys.

The 5.3m RIB will be stowed about 8ft above the poop deck on the starboard quarter, and while this larger RIB comes in at 670kg, it will be easily lifted into its cradle using Astra’s 6 tonne Palfinger crane.




MARMITE 2, Ribcraft 5.3m (Reproduced with permission: Ribcraft UK)


RIB Stowage Aft


Stowage position of RIBs on Astra created by Varadero Shipyard While the RIB stowage aft will permanently house the 5.3m RIB, for voyages in exposed waters the 4.2m RIB will also be transferred here to be safely stowed above the deck. At a height of approximately 8ft above the deck, this will allow ASTRA’s crew to safely move about below the structure, and it will keep the RIBs clear of any seas that might break across the deck No one wants their RIBs washed off the decks in heavy seas (and I have friends who have seen this happen!).


Using Astra’s 5.5m Zodiac to assess the viability of a raised stowage position for a similar sized RIB





Why Ribcraft?

West Coast Marine’s endorsement of Ribcraft was based on the experience of their clients. However, we also conducted our own assessment to determine which RIB manufacturer’s product range would be most suitable for Astra. When we saw Ribcraft’s ability to create a compact configuration for both RIBs, which in both cases you would expect to find on RIBs at least 1.5x that size, we knew we had found the right design. With both RIBs now in build, we caught up with Jason Purvey General Manager of Ribcraft and he shared with us “how extremely excited Ribcraft are to be part of such an amazing project and how they believe that both Astra and Ribcraft share the same core values and are both famous for their reliability, tough construction and ability to go anywhere, regardless of the weather.” Jason went on to point out that “inspired by their mother ship Astra, the Ribcraft 4.2 and 5.3 are built to commercial specifications and were custom designed in conjunction with Ribcraft experts to perfectly meet Astra’s exacting requirements. The new RIBs are fully built in-house and feature Ribcraft's signature commercial grade deep V hull, heavy-duty Hypalon inflatable tubes, navigation and communications equipment and are powered by twin outboard engines.”

In closing Jason said how “we very much look forward to having the new Ribcraft RIBs embarking on their Astra voyage.”

For more information on Ribcraft's product range, see: https://www.ribcraft.co.uk/

Why Marmite?


Rendering of MARMITE 1, Ribcraft 4.2m

(Reproduced with permission: Ribcraft UK)

Astra is very much a vessel that you either love or hate and, admittedly, the boys are largely in one camp and the girls are largely in the other! So Marmite became a bit of a nickname for Astra during the purchase process. (And if you don’t understand why, google it!) It would have been inappropriate to have renamed the main vessel (allegedly, shouted the girls), but it did seem appropriate for the support craft. The RIBs have therefore been named as ‘MARMITE 1’ and ‘MARMITE 2’, and there will no doubt be an appropriate ‘naming ceremony’ in due course!.


599 views

Recent Posts

See All

Comments


bottom of page