Gigha Sea Tours
Achamore House
Isle of Gigha
Argyll PA41 7AD
Tel: 01583 505 404
achamorehouse.com
About Our Boat
The Thalassa (ancient Greek for "the Sea") was built by Redbay Boats very much to the specifications requested by Gigha Sea Tours for our commercial activities, to provide the highest levels of both safety and comfort. Redbay is a long-established RIB builder in Northern Ireland, now with 30 years experience. In the west of Scotland if you see a RIB, it is more likely than not to be from Redbay. However with the Thalassa Redbay was asked to put in a number of features which they had not done before.
Ullman Dynamic Seats
Seating for high speed boats (or HSB for short) has generated an entire industry in the past decade, and fortunately so! The shocks that an HSB can encounter and pass on to its occupants may be considerable.
While obviously there is the clear need to tailor the speed of the boat to the sea conditions, some wave-impact shock is inevitable with any type of HSB, and RIBs are no exception. (The inflated tubes on the sides of RIBs provide a high degree of stability, but do not reduce the effect of wave-impact vibration.) So in creating the specification for our new boat, Don spent a great deal of time investigating various types of shock-mitigation seats currently produced in the world. Conversations with manufacturers and users in Holland, Norway, Italy, USA, the UK and finally Sweden led Don to the clear view that the seats designed and made by Ullman Dynamics were the best available.
Ullman Dynamics' seating concept arose 20 years ago from the interest and concern of a Swedish medical doctor in the spinal injuries being sustained by operators of HSB. Dr. Johan Ullman set out to design a seat which would ensure the optimum position of the body for absorbing impacts, combined with the best quality shock-mitigation technology. His company has been researching this technology since 1991, and brought out their first-generation seats in 1993.
Pretty much all shock-mitigation seats have substantial springs underneath, and heavy-duty padding on the seat itself. However, most of these have been found to actually amplify the energy of shock impact when the seats bottom out, creating a considerable risk for operators.
Most pod seats (widely seen in RIBs in the UK) are installed much lower than the Ullman seats, which puts one in a sitting posture more akin to that of a regular seat, with your feet under your knees and the spine shaped like a 'C'. This is position of the spine is very unfavourable for handling vertical shock impact.
The major difference with the Ullman seats is that you are kept in a three-quarter standing position, rather than sitting with all of your body-weight on a seat.
This serves several purposes. First of all, it enables your body to utilize the best shock-absorbing springs available in the world: your own legs. Secondly, it reduces the weight that is on the shock-absorbers of the seat itself, thereby reducing the force of wave-impact shock on the seat/body unit.
Thirdly by combining this 3/4 standing position / balanced riding posture with the passenger holding the grip-bar of the seat in front of them, the spine and skeleton are compelled to be in the best position for handling shock-impact. By contrast, if you are sitting fully on a seat in an HSB, and are strapped in with a 4-point harness, movement of the spine is very restricted, ensuring that all the forces hitting the body impact the neck and head, which can lead to whiplash injury.
About 75% of your body weight is supported by the Ullman seats, and that weight experiences the benefit of the thick neoprene seats and the very substantial and beautifully engineered spring under the seat. By having the spine in the best possible position for coping with wave-impact shocks, these elements combine to provide the safest HSB seating available in the world today.
The Thalassa is the first boat in Scottish waters to be fitted with Ullman Dynamic seats: we have 7 of these inside the cabin.
Our own experience has been dramatic from Day One. Two of us got a lift to Redbay from Campbeltown in an open 7.4m Redbay RIB at the end of November 2008. The day was a little choppy, and cold, but otherwise fine. That RIB was fitted with standard pod seats, and the (very experienced) skipper took us along at close to 30 knots most of the hour-long journey. With the padded pod seats it seemed we felt every bump and ripple, and an hour was as long a ride as I cared to take in that boat that day!
We then picked up the Thalassa, and came north to Gigha in the same conditions, and the difference was astonishing. With the Ullman seats you felt you could ride along all day without complaint or undue fatigue. The impression one gets is that of a much larger and heavier boat, rather than a 2-ton RIB which is 28 ft long. Yes, you still feel the impact of the waves, but that impact is softened and reduced considerably.
We believe these seats will be very popular with our passengers, but they are not the only shock-mitigation elements in the boat!
SKYDEX® IMBD Flooring
A great deal of fatigue and even injury can occur in an HSB via the shocks which are transmitted through the floor to ones ankles, and thence up the legs to the spine. Naval architects and boat manufacturers are looking at all methods to provide shock mitigation for people at sea, and now there is now a material to cushion the deck. SKYDEX is a patented cushioning material that adds shock absorption and vibration dampening properties to a range of products including blast mitigating flooring in some of the latest military vehicles. The SKYDEX system works by twin opposing urethane hemispheres bearing upon each other to create a spring which increases its resistance the greater the force that is applied to it. Different applications require 'tuning' the type and thickness of the material to the vibrational circumstance.
The combined technical knowledge of SKYDEX Technologies USA and the marine expertise of Shock Mitigation UK led to the creation of Impact Mitigating Boat Decking (IMBD). For this application SKYDEX engineers have tuned the performance of the cushion decking material to work for all RIBs and HSBs. This new SKYDEX IMBD material is now being used to reduce injury for the crews of military and professional RIBs & HSBs.
What the SKYDEX flooring does is primarily twofold: it helps reduce the major shock of wave-impact, as well as dramatically reducing the micro-shocks (measured in hundeths of a second) which are constantly present in any HSB moving at speed through choppy water. Their graphical respresentation of this data is well worth studying. SKYDEX IMBD is about 30mm thick, and has twin opposing urethane hemispheres bearing upon each other to create a spring which reduces shock and vibration. The Cross Hatch top layer is very firm underfoot, and anti-slip even when wet, amongst other very desirable characteristics.
Extra benefits of this flooring are its sound-absorbing qualities, and its thermal insulation. What we have found in the Thalassa is that inside the cabin (where we have SKYDEX IMBD fitted throughout) the boat is both warmer and quieter than one would expect, and there is a noticeable lack of vibration coming through the floor. We are delighted with this flooring, and expect it to become widely used in the coming years. (IMBD can easily be retro-fitted by the way, as it comes in 'tiles' which can be cut, and simply glued to the existing floor.) Thalassa is at present one of the few boats in UK waters to be fitted with it, and the is the first boat to be fitted with both Ullman Dynamic seats and SKYDEX flooring inside a cabin.
External Seating
With the Expedition model from Redbay, we knew we could get the best of both worlds, in that we could have sheltered seating inside the cabin, as well as good seating on the rear deck. Redbay had already put a 2-man bench on the engine hatch of other RIBs, but we asked them to also put a 4-man bench at the far back, with the rear rails as backrests. This way we ended up with external seating for six adults, for days when the weather is smiling. Inside the cabin we have seating for up to 7 passengers, but more on that below. The rear external seating is so successful, that Redbay will now be offering this as an option to all of their customers.
You're On Camera
One safety feature which Don felt was important to have installed was a small camera which is located on the outside rear top of the cabin facing the external bench seats, which provides a live feed to an 6" monitor installed just behind the wheel at the helm. This very small camera is from Iris Innovations, and is reverse-image, so people sitting on the port side (for example) appear correctly on the screen on the left. By being constantly live, the skipper is able to keep an eye on the passengers sitting outside. The camera automatically switches to infra-red at night, though that use will be rather limited!
Garmin Touch Screens and Forward-Facing Night Vision Camera
Thalassa was the first boat in the UK and possibly Europe to be fitted with the new Garmin 5015 touch-screen GPS plotter. The touch-screen aspect makes it much better for use while the boat is in motion, and as well one can pan (move) the chart around at the touch of a finger. This unit fits perfectly into the dashboard space that Redbay have in their mold for the 8.4m Expedition model, so its not difficult to imagine that other customers will opt for this soon. The screen can also be divided into sections allowing one to view the chart, radar, and the live feed from a forward-facing camera if one wishes. The forward-facing camera (also from Iris Innovations) is primarily of use at night as it switches automatically to infrared in the dark - very helpful for seeing buoys and kreel-pot floats.
The navigator also has an 8" Garmin touchsreen GPS plotter in front of him or her on the dash, so there's the benfit of a backup, as well as allowing the navigator to explore the charts without interefering with the skipper's screen.
The Electrics and the Radio
Thalassa is fitted with two batteries and smart-charging system, so on the one hand the bilge pumps should continue to work for several weeks on their own, and even then the other battery will still be ready for starting the engine. And all the dashboard electronics are turned off with a single key, making for a simple and safe procedure when the day is finished.
Good communication equipment is vital at sea, and we opted for the ICOM M603 VHF/DSC Marine Transciever, with a loudhailer. This model has an excellent speaker, making it easier to hear what is said on the marine frequencies, and it also has a very high receive specification, enabling you to hear weak signals even over the noise of the engine. All of this, and the Garmin equipment, help make the Thalassa a very well-equipped and seaworthy boat.
Secondary External Controls
Thalassa is the first 8.4m RIB to be built by Redbay with secondary external controls. Don had seen these on an 11m RIB that went to Sweden last spring, and the value of having controls that allow the skipper to easily toss a rope on a pier or pontoon, or grab a mooring, seemed tremendous. It means having both Garmin and Raymarine electronics working side-by-side, but they are compatible and the system works well. A canvas flap shields the controls from view when not in use, and the door to the cabin prevents their use when open, a further guard against a young passenger tinkering with them! Redbay and ourselves were very pleased with the design of the external controls layout, and how these were incorporated into the rear wall of the cabin, both simple and elegant. And they are in the optimum location for the skipper. A great job, well done!
The Engine
Yamaha has breathed new life into their marine diesel division, largely thanks to the enthusiasm of Redbay over the past decade, who are their major European importer. These inboard diesels have shown themselves to be trustworthy and reliable, and at the same time giving very good fuel economy and power. Thalassa is the first of the 8.4m RIBs from Redbay to be fitted with the new and most powerful of the Yamaha engines, the ME432HO. This engine provides 315 hp, and fitted with the TRP Duo-prop Hydra-drive gives the Thalassa a top speed in excess of 36 knots. Cruising speed will usually be about 26 to 29 knots, but it is good to know that the power is there to give that extra speed when it is needed.
The Big Tank
Refueling here on Gigha always involves some extra effort, as we need to bring the diesel to the South Pier in a bowser, so we asked Redbay to make the fuel tank larger than their standard 315 litre size. At first they said it couldn't be done, but when nudged they allowed that if we did away with the footwell in the forward storage area, it would be possible to gain an extra 85 litres. This 400 litre tank gives the Thalassa the advantage of being able to make longer journeys between refueling. It also gives extra peace of mind to know that she can rund continuously for over 13 hours at good speed before she needs to be filled up again.
To book a ride call us on tel: 01 583 505 404 or email: info@gighaseatours.co.uk
