FC01
Our first sub, S101 was launched 23 years ago thus starting a business that has now provided several hundred man-years of employment. We decided it was time we did it again. FC01 is to be our own submarine that will remain based in Plymouth instead of disappearing to the far corners of the planet just a few weeks after launch, as is usually the case. The new sub takes it's type numbers from the code name ‘Fruit Cake’ an in-joke that stuck as it signifies our form of indulgence.
As a company we pride ourselves on being ‘customer driven’ - but one thing we like about FC is that although it has been designed with the experience of 23 years of submarine building, it is entirely the product of our own requirements.
The design addresses many of the shortcomings of traditional mini-subs. It is intended to transit out under diesel power requiring good freeboard and stability whilst making the trip enjoyable for the 2 crew. The 200° ‘hyper-hemisphere’ on the deck provides comfortable car type seating, slightly staggered to make best use of the available shoulder room. When dived the crew are treated to the floating-in-space feel of all round acrylic whilst the 10° below the equator provides a distortion free view of the sea-bed close to. Although the view directly forward and down is occluded, the bow is fairly pointed to reduce this as far as possible.
In the interest of reliability and to keep cost under control the submarine is an exercise in relative simplicity. Without taking a technological step backwards, there are no more components than there need to be. Ease of use has been given particular importance, hence features like the on-board automatic battery charger requiring just an extension lead to the marina plug socket.
The steel hull has been designed to BS5500 to be safe to 180m but the maximum operating depth will be 100m to simplify rescue asset requirements. The hull is being built at the MSubs workshop and will be the third pressure hull we have made ourselves. The exterior will be entirely faired by an all enclosing GRP hull made in two pieces split along the vertical centreline. This forms a large main ballast tank which keeps the hull and external equipment dry whilst on the surface. As the boat will spend many months on a marina berth this will avoid corrosion issues. Also, as all the acrylic is above the waterline, the age old problem of cleaning windows is solved. Previously we had to slip into the water whilst the marina manager was not looking to accomplish this prior to a dive. AP6 although wonderful in every other way was a nightmare to keep clean. Every 3 days the green algae had to be carefully cleaned from around 5 m2 of acrylic.
The sub is entered through the 550Ø hatch in the top of the hemisphere dropping down onto the two car type seats. The forward of the two has the dive controls consisting of an aircraft type yoke controlling the aft planes and rudder. Beneath the seats are the batteries and below the batteries is a motorised trim weight for low speed pitch control.
An advanced navigation suite is fitted, GPS whilst on the surface and a 4 beam Doppler velocity log whist dived that will track to an accuracy of a few meters per hour. This, together with forward scanning sonar will enable us to locate and film ship wrecks never before explored, of which there are many in this part of the world. The sub is due to be launched sometime in 2010.
