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Siraj-1 / Bladerunner

The Bladerunner boat is one of the most adventurous items that have been imported into the Armed Forces Armed Services Organization in recent years. It was originally designed as a racing boat and is the fastest speed record in its class weight boats. The Bradstone Challenger, a Bladerunner 51, shot to fame in 2005 by rounding Britain in just over 27 hours, at an average speed of 63.5mph. Its hull was built to run at high speeds in rough water. The Bladerunner 51, weighing 16 tons and 15.5 meters (45 feet) long can reach a maximum speed of 65 knots.

Bladerunner 51, designed by Lorne Campbell, is a 15.5 m / 51 ft long luxury yacht. Her top speed is 60.0kn and she boasts a maximum cruising range of 300.0nm with power coming from two 1000.0hp Caterpillar C-18 ACERT diesel engines. She can accommodate up to 2 people. The Bladerunner hull form was conceived by some of Britains most successful and experienced offshore racing professionals in both design, engineering and competition. Naval Architect Lorne Campbell heads up the hull design, a quietly spoken man with over 40 years experience in designing class winning high performance powerboats, with an enviable 100 race wins and 20 World and National championships to his credit. Together with 1995 2 litre World Champion, Founder and Director of ICE Marine Jeremy Watts, they set out to develop the Bladerunner series for multiple applications where improved efficiency, ride and handling were the primary objectives.

With over 40 years of extensive development and technical expertise behind the company, combined with a comprehensive 20 year development program for the Bladerunner Air Entrapement Monohull design, the Bladerunner Series now ranges from 35-ft to 51-ft, with a number of very credible World and national records under its belt, including the current holder of the outright Round Britain World Record in 27hrs & 10 minutes, smashing the previous record by more than 3 hours.

Great amounts of power are required to accelerate a watercraft to a speed where it transitions from its displacement mode (hull buoyant lift) to its planing mode (hull dynanmic lift) or "critical speed". Maximizing lift and minimizing drag at the critical speed is needed or the watercraft will not plane. Watercraft hull drag reducing designs in the past have included stepped hulls, spray rails, running strakes, surface effect and/or watercraft hull high lift/drag (L/D) attachments or appendages such as trim tabs, flow interceptors (aka "spoilers"), and hydrofoils. Because of viscous, wetted surface drag of a watercraft hull, efficiency at planing speeds is generally poor with a low L/D ratio. To achieve low drag at planing speeds, hull immersion in the water must be reduced by lifting a greater portion of the hull above the water surface or by ventilating the submerged portions of the hull to minimize the wetted hull surface.

A number of watercraft hulls of various designs incorporate entrapment tunnels to try to resolve these issues. These tunnels are generally downwardly open concavities formed in the hull and extend aft from near the bow. The ceilings of such entrapment tunnels typically slope downward from near the bow towards the stern such that rear portions of the tunnels, including parts of their ceiling, are submerged at rest. This structure serves to channel air and/or water under the hull. Because the tunnels are more shallowly immersed than the lower portions of the hull, they entrap air under the hull for more lift and their additional drag is mitigated by tunnel ventilation which reduces wetted surface area. With increasing speed and hull lift, tunnel immersion in the water is reduced or eliminated. As more of the hull is lifted out of the water the tunnel sides serve to improve directional, pitch and roll stability.

Despite the improvements found with the deep V hull design, planing boats can provide uncomfortable rides. With too high a running trim, the bow pitches up over the crest of the wave, then plunges downward slamming back to the free surface. Another type of slamming occurs when the hull completely leaves the water, and is called re-entry slamming. Conventional deep-V hulls will have excellent seakeeping if they can be controlled to run at speed with low trim while remaining upright (i.e., not heeled to either side). A particularly dangerous condition in which to have excessive roll is when turning in rough seas from a head to a quartering to a beam sea. Heeling over during this maneuver causes excessive pounding and uncomfortable to dangerous levels of roll.

An entrapment tunnel watercraft vessel has three hulls consists of a main hull and two amas arranged outboard of the main hull with the keels of the three hulls being parallel. The main hull is a narrow, vee hull with variable, rearwardly decreasing deadrise. The amas have very fine bows and narrow, asymmetric deep-V hulls, with nearly vertical slab outboard sides above their keels and variable reverse deadrise on their inboard sides with the reverse deadrise angles decreasing from bow to stem. The tunnels on each side of the main hull are formed by three distinct surfaces, the sides of the main hull above its chine, the reverse deadrise inboard sides of each ama upward from their keels and a ceiling surface transversely spanning the aforementioned sides and having rearwardly increasing deadrise and rearwardly decreasing width. The tunnel ceilings slopes down from the bow to a section aft of midship where the ceiling height above the keel remains essentially constant. At speed the craft generates substantial amounts of lift and positive trim, thereby reducing the forward wetted length of the immersed tunnel ceiling and the apex of the ceiling is approximately at the craft dynamic waterline. As a result the watercraft vessel has improved seakeeping, stability and weight carrying ability.

The Bladerunner Air Entrapement Monohull design comprising, a pair of amas (outer side hulls or sponsons) symmetrically disposed about the hull centerline, each of which amas defines an entrapment tunnel. The watercraft with entrapment tunnels and amas improve a narrow vessel's stability at rest or at speed and improve the vessel's ability to achieve critical planing speeds and carry high loads. watercraft with entrapment tunnels and amas improve a narrow vessel's stability at rest or at speed and improve the vessel's ability to achieve critical planing speeds and carry high loads. The interaction between the center hull and the amas sponsons is the key to the boat's stability. When running in waves, and motions that cause an am to dip into the water generates and upward spray sheet into the entrapment tunnel; the tunnel ceiling translates the force of the trapped compressed air and spray into a righting moment, countering the disturbing motion. The larger the disturbance, the greater the spray generated and hence the greater the stabilizing righting moment force.

After it was desired by the military commanders of the Guard but prevented from official sale to Iran, efforts began to buy from a specific route without informing the British. In 2006 the UK Department for Trade and Industry blocked the country’s first attempt to buy it. Iran was not deterred, and after changing hands a further two times, the US discovered the boat was due to be transferred to South Africa where it would be loaded onto a Hong Kong-flagged Iranian merchant vessel for the voyage to the Gulf.

In early 2009, after a successful acquisition, the boat was delivered to Iran by a carrier in South Africa via an intermediary carrier. Although the US security forces learned about the incident a bit later, they informed the Navy of the fact that they were pursuing the ship by a naval ship in the Indian Ocean. Thus, unilateral US sanctions on this issue were ineffective in spite of turning to military force.

On 24 August 2010 Iran inaugurated the production lines for two types of high-speed assault boats called Seraj 1 and Zolfaqar. Defense Minister Ahmad Vahidi and the Islamic Revolution Guard Corps Navy Commander Ali Fadavi attended the ceremony. Seraj 1 and Zolfaqar speedboats are manufactured at the marine industries complex of the Defense Ministry. Vahidi said Seraj 1, with a fiberglass bodywork, can shoot rockets and it is equipped with an electronic navigation system.

In Decmber 2012 Commander of the Islamic Revolution Guards Corps (IRGC) Naval Force Rear Admiral Ali Fadavi said his forces are due to mass-produce and arm home-made Bladerunner speedboats in the next Iranian year (starting on 21 March 2013). "The vessel will be mass-produced in 1390 (March 2011-March 2012) based on the specified timeline," Fadavi told FNA, and further voiced satisfaction with the production trend. The commander said Iran has already mounted different types of weapons, including missile launchers, onto the country's speedboats, and noted that the Bladerunners, too, would be equipped with different arms due to their unique features.

Iran's Defense Minister Brigadier General Ahmad Vahidi had earlier announced that the use of speedboats is at the heart of the Iranian Navy's operational doctrine since high-speed vessels have already proved highly efficient in fighting back US heavyweight warships. He further announced that Iran is now capable of manufacturing speedboats which can traverse at 60 to 70 knots per hour, yet the country is still seeking to increase the speed of these vessels to 80, 90 and even 100 knots.

Previously, Bladerunner was only involved in sailing competitions outside of Iran, and Iranian maritime industry specialists modified it to carry a 107-mm continuous 11-inch tubular rocket launch vehicle, a sea-range radar with a range of 30 kilometers and a shotgun 12. 7 mm, and then equipped with rocket and torpedo rocket launchers and is widely used to serve operational units in all southern waters of Iran. The maximum speed of this boat is more than 70 knots, equivalent to 130 km/h, and is called the Siraj-1 in its Iranian version.

Siraj-1 boat has a surface search radar for rocket targetting and is suitable for tropical climates. The hull is made of fiberglass and equipped with native telecommunication facilities and electronic navigation. The design of the cabin in this boat is such that at high speeds inside the cabin, the altitude changes caused by moving on the water and the slight noise is not felt. Also, in the stormy conditions of the sea, the occupants will not feel the intensity of the waves.

After seeing the high performance of this boat in recent years, the British police, as the country's manufacturer of this fast-moving boat, have been thinking of using it as a manned or unmanned person for high speed and law enforcement in the city of London. This sample is equipped with surface search radars and stable camera.

Boat Name Bladerunner 51
Date 2007
Length 51ft ( 15.53m )
Power 2 x 1000hp diesel
designed by ICE Marine
radarU/I surface search
rockets11 x 107mm

Siraj-1 / Bladerunner Siraj-1 / Bladerunner Siraj-1 / Bladerunner Siraj-1 / Bladerunner Siraj-1 / Bladerunner Siraj-1 / Bladerunner Siraj-1 / Bladerunner Siraj-1 / Bladerunner Siraj-1 / Bladerunner

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Page last modified: 18-07-2019 16:02:11 ZULU