S104
Totally indulgent personal mini sub.
Steel-Fish S104 Micro sub
.All new S104 Micro. Single seat and ultimate performance, speeds up to 12kn and range over 100 miles. X planes give superb manoeuvrability at all speeds. Fighter style cockpit and flown with responsive aircraft style side-sticks. Full variable ballast system to noiselessly hover close to the sea bed. The overall length is 5m and will float in just 725mm of water, mid-thigh to an average person.
At 1500 kg the Micro-sub is easily launched from a trailer or yacht. Generous freeboard, stability and reserve buoyancy allows entry and egress on the surface. Very easy to operate with intuitive controls. Any capable person can by taught to operate this vehicle with a short training course.
These were the design objectives which took me quite some time to resolve. Low cost was the other important factor. Composite construction for both pressure hull and fairings has been chosen to provide complete freedom to shape of the critical components and a super smooth exterior finish. The main pressure hull is built on a rotating former and is 20mm thick resulting in a crush depth of 800m, 8 times the operating depth of 100m. The thermoformed acrylic hatch hemisphere has been used in vehicles with a 200 m operating depth but has a 2,500m crush depth. The choice of composite over steel means maintenance inside ballast tanks for example is never going to be a problem.
The ellipsoidal pressure hull centre section is a roomy 860 diameter with generous leg room and plenty of seat height adjustment. The two control sticks fall easily to hand fitted to the two side control consoles. One side is air and ballast with all the required displays and the other side is electrical for propulsion control and monitoring. The navigation display sits directly in front of the pilot and slides forward to make entry and exit easier. There is a full HD camera fitted in the bow pointing forward and down feeding into a tablet computer to cover the area visually occluded by the bow section.
Aft of the pilot compartment behind a watertight bulkhead is the battery. The maximum size battery that can be fitted is 30kW hr made up of prismatic LiPO4 cells. These are the super safe variety. The standard battery is 20 kW hr which due to extremely low water resistance will provide more power than most people will ever use. This allows almost complete autonomy enabling adventurous expeditions far from the launch point with only minimal surface support.
At 5kn the 20kW hr battery will give a range of 100 miles. The 30kW hr battery will give the same range at 6kn, or put another way, in an 8hour day you could cover 60 miles at 8kn. This is military performance.
Power is provided by a direct drive super quiet brushless DC motor in the tail driving a 5 blade GRP propeller. The maximum motor speed is 800 RPM, power 10kW continuous, 20kW for short bursts. Most of the time the motor will be turning at less than 400 rpm. Also found in the tail section is the 24V aux battery and the motor control unit. This space is accessed if required by removing the O ring sealed after tail section complete, bit if all is well there is nothing in here that needs routine attention. The tail is fixed securely in place with an internal clamp system released by hydraulic pressure. The action is reminiscent of some of the military hatches I have designed in the past.
Below the pilot is a 30L variable ballast tank to compensate for different pilot weights (in addition to fixed weights) and to provide fine control of buoyancy. The brass 3 cylinder piston pump fitted behind the pilot runs at 8L/min and is directly driven by a brushless DC motor. There is also a basic hydraulic system fitted to operate the aft hull release, emergency buoy release, drop-weight release and the vent valves. The small pump is manual. A weight can be released off the bottom to gain an instant 100kg of buoyancy and the tower fairing can be released to float up on a cable if the vehicle is unable to surface.
Operation is made easier by placing the HP air cylinders inside the removable nose fairing. These are standard 12.5 litre SCUBA cylinders which can be detached and refilled at the local dive shop. In this space is also the emergency oxygen supply, good for 72 hours. The daily use O2 is kept inside the sub in a pair of slim 3L cylinders, each good for 22 hours. The CO2 scrubber is fitted above the pilot’s feet. 2 kg of Sofnolime 1025 will last 8 hours with sufficient refills stowed either side of the main battery.
Dynamic control is by two sticks each hydraulically coupled to a diagonal pair of aft planes. Push both sticks forward and you go down, pull back for up. Push port forward and starboard aft and you turn to starboard, like bike handlebars. There is a motor driven trim weight in the pilot’s compartment running in a housing between the pilot’s feet. This is very useful to control the height above the sea bed when moving slowly.
Surfacing is achieved by blowing the two ballast tanks, one forward and one aft providing approximately 250 kg of reserve buoyancy. The blister tanks at the waterline greatly enhance the surfaced stability. There is enough HP air on board to blow the tanks 20 times. To dive, the air is released from the tanks through two hydraulically operated vent valves similar to those I have designed for the Triton subs and almost every submersible built in the UK in the last 20 years. There are float switches in the tanks to indicate when the blow is complete and to sound an alarm if any attempt is made to open the hatch too soon.
Build quality is to classification Rules and standards. The hull is made in the same facility as our GL approved GRP for tourist submarines. Pressure test in our own pot is to 200m.
At 1500 kg the Micro-sub is easily launched from a trailer or yacht. Generous freeboard, stability and reserve buoyancy allows entry and egress on the surface. Very easy to operate with intuitive controls. Any capable person can by taught to operate this vehicle with a short training course.
These were the design objectives which took me quite some time to resolve. Low cost was the other important factor. Composite construction for both pressure hull and fairings has been chosen to provide complete freedom to shape of the critical components and a super smooth exterior finish. The main pressure hull is built on a rotating former and is 20mm thick resulting in a crush depth of 800m, 8 times the operating depth of 100m. The thermoformed acrylic hatch hemisphere has been used in vehicles with a 200 m operating depth but has a 2,500m crush depth. The choice of composite over steel means maintenance inside ballast tanks for example is never going to be a problem.
The ellipsoidal pressure hull centre section is a roomy 860 diameter with generous leg room and plenty of seat height adjustment. The two control sticks fall easily to hand fitted to the two side control consoles. One side is air and ballast with all the required displays and the other side is electrical for propulsion control and monitoring. The navigation display sits directly in front of the pilot and slides forward to make entry and exit easier. There is a full HD camera fitted in the bow pointing forward and down feeding into a tablet computer to cover the area visually occluded by the bow section.
Aft of the pilot compartment behind a watertight bulkhead is the battery. The maximum size battery that can be fitted is 30kW hr made up of prismatic LiPO4 cells. These are the super safe variety. The standard battery is 20 kW hr which due to extremely low water resistance will provide more power than most people will ever use. This allows almost complete autonomy enabling adventurous expeditions far from the launch point with only minimal surface support.
At 5kn the 20kW hr battery will give a range of 100 miles. The 30kW hr battery will give the same range at 6kn, or put another way, in an 8hour day you could cover 60 miles at 8kn. This is military performance.
Power is provided by a direct drive super quiet brushless DC motor in the tail driving a 5 blade GRP propeller. The maximum motor speed is 800 RPM, power 10kW continuous, 20kW for short bursts. Most of the time the motor will be turning at less than 400 rpm. Also found in the tail section is the 24V aux battery and the motor control unit. This space is accessed if required by removing the O ring sealed after tail section complete, bit if all is well there is nothing in here that needs routine attention. The tail is fixed securely in place with an internal clamp system released by hydraulic pressure. The action is reminiscent of some of the military hatches I have designed in the past.
Below the pilot is a 30L variable ballast tank to compensate for different pilot weights (in addition to fixed weights) and to provide fine control of buoyancy. The brass 3 cylinder piston pump fitted behind the pilot runs at 8L/min and is directly driven by a brushless DC motor. There is also a basic hydraulic system fitted to operate the aft hull release, emergency buoy release, drop-weight release and the vent valves. The small pump is manual. A weight can be released off the bottom to gain an instant 100kg of buoyancy and the tower fairing can be released to float up on a cable if the vehicle is unable to surface.
Operation is made easier by placing the HP air cylinders inside the removable nose fairing. These are standard 12.5 litre SCUBA cylinders which can be detached and refilled at the local dive shop. In this space is also the emergency oxygen supply, good for 72 hours. The daily use O2 is kept inside the sub in a pair of slim 3L cylinders, each good for 22 hours. The CO2 scrubber is fitted above the pilot’s feet. 2 kg of Sofnolime 1025 will last 8 hours with sufficient refills stowed either side of the main battery.
Dynamic control is by two sticks each hydraulically coupled to a diagonal pair of aft planes. Push both sticks forward and you go down, pull back for up. Push port forward and starboard aft and you turn to starboard, like bike handlebars. There is a motor driven trim weight in the pilot’s compartment running in a housing between the pilot’s feet. This is very useful to control the height above the sea bed when moving slowly.
Surfacing is achieved by blowing the two ballast tanks, one forward and one aft providing approximately 250 kg of reserve buoyancy. The blister tanks at the waterline greatly enhance the surfaced stability. There is enough HP air on board to blow the tanks 20 times. To dive, the air is released from the tanks through two hydraulically operated vent valves similar to those I have designed for the Triton subs and almost every submersible built in the UK in the last 20 years. There are float switches in the tanks to indicate when the blow is complete and to sound an alarm if any attempt is made to open the hatch too soon.
Build quality is to classification Rules and standards. The hull is made in the same facility as our GL approved GRP for tourist submarines. Pressure test in our own pot is to 200m.