ANTI TERRORIST BOAT BARRIER SYSTEM A Proven Barrier System Tested and Installed Worldwide Pneumatic Barrier System, designed and supplied to withstand 1,000,000 ft-lbs of Kinetic energy which represents a boat 38 foot (11.6 metres) long with a weight of 8300 lbs (3773 kg) hitting the barrier system at 52 knots (60 mph) Highly visible barrier system with an expected life in excess of 20 years
1. PROPOSED SOULTION TYPICAL BARRIER INSTALLATION A Dunlop GRG Boat Barrier System consists of two major sub assemblies, the floating barrier and the mooring system. Both these elements are designed to withstand the force of an attacking seaborne threat and the environmental conditions. Dunlop GRG has partners with the capability of carrying out Security assessments, provide recommendations, carry out a site survey, providing and installing the full barrier system. The barrier is a very low maintenance product which is easily operated, training is provided to the client to ensure the integrity of the system is maintained. 1.1 FLOATING BARRIER The floating barrier consists of the pneumatic Dunlop barrier units plus buoys, connections and gate systems. The standard Barrier units are supplied at 2.40 metre Diameter x 25 metres long, though Dunlop can design and manufacture a range of barrier sizes to suit customers requirements The Barrier unit is fabricated from black vulcanized polychloroprene rubber coated textile. Highly visible orange materials are an optional extra where visual impact is necessary. Each pneumatic unit is fitted with valves to allow inflation to the operating pressure of 70 mbar (1 psig). The same valves are used for pressure testing during maintenance procedures and for deflation. The barriers are designed to withstand at least double the operation pressure. Various buoy designs are available and typically the barrier units and buoys will be connected together using standard shackles and chain links, typical examples are shown below.
Barriers can be designed with different gate systems depending on the type and frequency of traffic, single or multiple gates can be built into the system. Small gates can be incorporated for patrol craft, ferry traffic, support craft etc. to enter and exit the protected area. For naval ships and submarines to access and exit the protected area larger gates can be integrated. A Quick Release Hook (shown below) mounted on a gate buoy with a swivel arrangement is one method to ensure the gate opening and closing is a simple procedure taking between 10 15 minutes. 4 TON BUOY GENERAL ARRANGEMENT TYPICAL QUICK RELEASE HOOK FOR GATE BUOY The end termination of the barrier is clearly dependent on the location of the barrier system. Dunlop have previously used a variety of methods to secure the barrier to the harbor wall or onto a beach position. Below is one solution of how to attach the barrier to a harbor wall using a simple float to allow for tidal changes. POSSIBLE END TERMINATION SOLUTION
1.2 MOORING SYSTEM The Anchor system is designed for the environment conditions and sized to match the strength of the barriers internal reinforcing wire which has a minimum ultimate tensile strength of 445 Kilo Newtons (100,000 lbs force). As the barrier is deflected by the impact of an attacking craft the mooring system will absorb and dissipate impact energy. An array of mooring systems are available to provide the connections to the barrier, the standard system offered is designed to meet with the default operational conditions. Where operational conditions alter our buoy and anchor system are reviewed and modified. SYSTEM TYPICAL ANCHOR AND MOORING 2. POSITIONING The Dunlop Barrier systems are configured for each application. Stand-off distances are important to protect the asset and to the provide time for other responses to become effective. Generally 122m is the minimum safe distance to protect an asset from 2000 lbs of explosive. At this distance it is predicted that an asset will sustain some damage but will perform its functions, however life will be threatened.
At a standoff distance of 366m the same sized charge will give personnel survivability and asset will be undamaged. It is recognised that with some projects these distances will not be available, in this instance the barrier system should be used in conjunction with other security measures. 3. OPERATING CONDITIONS Each Barrier system is designed for the environmental conditions in which it will operates. For Dunlop GRG to design a Barrier the following information is required: Ground Conditions, Current Speed, Wave Height (Hs), Operating Temperature Range, Tidal Range, Wind Speed & Water Depth. When the environmental conditions are unknown Dunlop will base the design of the system on the Default Operational Conditions which are shown below. It must be noted that once details of the environmental conditions are finialised this can alter the configuration of the Barrier system. Increase in current speed will impact on the chain sizes; decrease in wind speed will impact on the quantity of buoys and anchors. DEFAULT OPERATING CONDITIONS Item Condition Default 1 Ground Conditions Fine Grain Sand, Light Shingle 2 Current Speed 0.6 m/s 3 Wave Height 1.25 Metres Hs 4 Annual Operational Temperature Range -10 C to +50 C 5 Tidal Range 1 Metres 6 Wind Speed 100 Knots (6 Tonne Loading) 7 Water Depth 3 metre to 50 metre.
4. INFLATION AND INSTALLATION The Dunlop GRG Barrier is a relatively lightweight product. Easily transported and stored it can be quickly deployed and retrieved for reuse in different positions. Even though the barrier has a large mass it has high buoyancy making the units easy to move during installation. A Barrier Lifting beam is available as an optional extra. Barriers are manufactured from a very high abrasion resistant material and can be launched down a ramp. A Dunlop GRG Barrier is a highly buoyant product with a weight of 1200kg its draft is less than 100mm. Inflation of a barrier will take between 10 to 15 minutes. 5. BALLISTIC TESTING The Barrier has been tested against multiple small hand guns with 50 calibre, 7.63 and 5.56 NATO. The worst penetration was a 4mm hole left by 0.375 magnum. Other rounds just separated the fabric and closed back over. The 70 mbar (1 psi) inflation pressure of the Barrier ensures no catastrophic failure. The puncture self seals and air pressure is only slowly released allowing time for secondary security measures to be effected.
6. KEY FEATURES During the design and development of the product there was measurable criteria stipulated to gauge how effective the barrier would be in preventing an attack. Key points in the barriers design are: The barrier will delay an attacking craft for a minimum of 5 minutes The barrier will cause severe damage to a craft attacking at the maximum design impact speed. Crew in an attacking craft hitting the barrier at maximum speed will be incapacitated unless they were wearing restraining harnesses and helmets. In conjunction with the security issues there have been other areas of harbour activity to consider. When Naval Shipping accidentally hit a barrier during harbour maneuvers the paintwork on a ship nor the RAM tiles on a submarine will be scratched or damage. Where a secured harbour area has public activity the barrier provides a safe cushion against accidental collisions, with little chance of harm to the general public. If the barrier was accidentally punctured by the general public the inflation pressure is so low the release of air is not hazardous to human life. Maintenance is very low, very few metallic parts to corrode and cause failure. 7. EXISTING INSTALLATIONS The Dunlop Barrier System has been successfully installed at a variety of bases and ports throughout the world with the first barrier installation in 1992. Below are a few examples of the Dunlop Barrier System in use today. US Navy Mediterranean base, Barrier installed 2002.
Typical Submarine Protection Barrier Gate Opening Procedure at San Diego 8. MANUALS, TRAINING AND SPARES Lifecycle durability and low maintenance requirements are achieved through the design of the barrier units and the materials selection. During the life of the barrier the inflation pressure will need occasional monitoring to ensure it is maintained at the specified pressure of 70 mbar (1 psi), particularly at times of seasonal climate change. With each barrier system, operational and maintenance instruction will be provided. As part of a barrier project Dunlop GRG can present a training course for customers, detailing the requirements for operation and maintenance of the barrier system. As part of a barrier project Dunlop GRG will supply spare parts for 1 years operation. The spare parts list will be determined in accordance with the barrier design and maintenance schedule. 9. WARRANTEE Each barrier is provided with a 12 month warrantee period against material defects and workmanship. Extended warranty options can be negotiated for individual barrier systems.
10. OPTIONAL EXTRAS Inflation/Deflation Typical portable Air Blowers for Barrier inflation/emptying capacity 16m 3 /min. The Barrier units can be inflated using a low pressure blower. The unit shown above has a petrol engine, however if a diesel engine is preferred the item would not be man portable due to the additional weight. Inflation time using the above blower for 1.8m x 25m barrier would be approximately 6 to 8 minutes (approx. 80m 3 ) There are blower units which use available airlines, these units use a system which decreases line pressure and increases delivered volume. Depending on the location where barriers are to be launched an inflation system can either be supplied or recommended. Dunlop GRG can also provide a range of additional equipment to enhance the barrier such as: Dunlop Barrier Duck Dive Net, to prevent intrusion by Jet Ski type craft. Swimmer Detection Systems. Navigational Lighting. Barrier covers printed with warning signs. Tamper alarms for barrier connections. 11. REFERENCE DOCUMENTS US Naval Facilities Engineering Service Center, Technical Memorandum 31-01-01 Full Scale Testing of Dunlop Barriers. Prepared for Naval Criminal Investigative Service Antiterrorism Force Protection CNO-N34/NCIS-24. US Naval Facilities Engineering Service Center, Technical Report TR-6031-OCN Boat Impact into a Dunlop Barrier, a Numerical Model. Prepared for Naval Criminal Investigative Service Antiterrorism Force Protection CNO-N34/NCIS-24.