|
Stabilizer (ship)
Ship stabilizers (or stabilisers) are fins or rotors mounted beneath the waterline and emerging laterally from the hull (watercraft), hull to reduce a ship's ship motions#Rotational motions, roll due to wind or waves. ''Active fins'' are controlled by a gyroscope, gyroscopic control system. When the gyroscope senses the ship roll, it changes the fins' angle of attack so that the forward motion of the ship exerts force to counteract the roll. ''Fixed fins'' and bilge keels do not move; they reduce roll by hydrodynamic drag exerted when the ship rolls. Stabilizers are mostly used on ocean-going ships. Function Fins work by producing lift (force), lift or downforce when the vessel is in motion. The lift produced by the fins should work against the roll moment of the vessel. To accomplish this, two wings, each installed underwater on either side of the ship, are used. Stabilizers can be: *Retractable - All medium and large cruise and ferry ships have the ability to retract the fins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnus Effect
The Magnus effect is a phenomenon that occurs when a spin (geometry), spinning Object (physics), object is moving through a fluid. A lift (force), lift force acts on the spinning object and its path may be deflected in a manner not present when it is not spinning. The strength and direction of the Magnus force is dependent on the speed and direction of the rotation of the object. The Magnus effect is named after Heinrich Gustav Magnus, the German physicist who investigated it. The force on a rotating cylinder is an example of Kutta–Joukowski theorem, Kutta–Joukowski lift, named after Martin Kutta and Nikolay Zhukovsky (scientist), Nikolay Zhukovsky (or Joukowski), mathematicians who contributed to the knowledge of how lift is generated in a fluid flow. Description The most readily observable case of the Magnus effect is when a spinning sphere (or cylinder) curves away from the arc it would follow if it were not spinning. It is often used by football (soccer) and volleybal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USS Bronstein (DE-1037)
USS ''Bronstein'' (FF-1037) was the lead ship of her class in the United States Navy. She was named in honor of Assistant Surgeon Ben Richard Bronstein, who was killed in action on 28 February 1942 when was sunk by a German U-boat off Cape May, New Jersey. ''Bronstein'' was commissioned on 16 June 1963 as DE-1037 under the command of Stanley Thomas Counts. She was decommissioned 13 December 1990 and struck from the Navy list on 4 October 1991. ''Bronstein'' was disposed of through the Security Assistance Program as a foreign military sale on 12 November 1993. She was transferred to Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ... on 12 November 1993 where she served as ARM ''Hermenegildo Galeana'' (F202). References External links *NavSource.org Bronstein B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USS Gyatt
USS ''Gyatt'' (DD-712/DDG-1/DDG-712) was a of the United States Navy operated between 1945 and 1968. The ship was named for Edward Gyatt, a United States Marine Corps private and Marine Raider killed during the Battle of Guadalcanal. She was laid down in 1944, commissioned in 1945, and missed combat during the Second World War. In 1955, she was converted into the world's first guided missile destroyer (DDG) to evaluate the RIM-2 Terrier surface-to-air missile and the practicality of similar weapons. Her service contributed to the development of dedicated air-defense missile escorts and of later anti-air missiles by identifying flaws in both designs. Her goal was completed in 1962, and she was converted into a floating test bed for radars and other electronic equipment. By 1969, structural issues caused by missile launches forced her to be decommissioned; she was sunk as a target in 1970. Namesake Edward Earl Gyatt was born on 4 September 1921, in Syracuse, New York, and l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USS Hamilton (DMS-18)
The second USS ''Hamilton'' (DD–141) was a in the United States Navy following World War I, later reclassified DMS-18 for service in World War II. Namesake Archibald Hamilton was born c. 1790, the son of Secretary of the Navy Paul Hamilton. He was appointed Midshipman on 18 May 1809 and assigned to work with a new kind of hollow shot needed by frigate . He next sailed for Europe on on 31 January 1811 carrying dispatches for American officers in the Mediterranean. On his return to the United States, Hamilton was assigned to on which he won commendation from his commanding officer, Captain Stephen Decatur, for gallantry in action during the capture of British frigate on 25 October 1812. Decatur selected him to bear the captured British flags to Washington. Appointed Acting Lieutenant on 21 December 1812 and Lieutenant on 24 July 1813, Hamilton served throughout the War of 1812, only to be killed shortly after the Treaty of Ghent had formally ended the war. Because of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USS Osborne (DD-295)
USS ''Osborne'' (DD-295) was a in the United States Navy following World War I. She was named for Weedon Osborne. Naval Service ''Osborne'' was laid down 23 September 1919 at Bethlehem Shipbuilding Corporation, Squantum, Massachusetts; launched 29 December 1919; co-sponsored by Mrs. Elizabeth Osborne Fisher, sister of Ltjg W. E. Osborne and Mrs. C. H. Cox; and commissioned 17 May 1920. Commissioned into a peacetime navy curtailed by a retrenching Congress, the undermanned four-stacker departed Boston, Massachusetts 25 June to join DESRON 3, Atlantic Fleet. The limited coastal operations of 1920 were supplemented by 2 months of fleet exercises and battle problems off Cuba during the first quarter of 1921. Whether operating out of Charleston, South Carolina, her normal base of operations, or out of the Brooklyn or Philadelphia Navy Yards ''Osborne'' regularly steamed southward early each year for these competitive exercises and large scale tactical maneuvers. These useful ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Director (military)
A director, also called an auxiliary predictor, is a mechanical or electronic computer that continuously calculates trigonometric firing solutions for use against a moving target, and transmits targeting data to direct the weapon firing crew. Naval warships For warships of the 20th century, the director is part of the fire control system; it passes information to the computer that calculates range and elevation for the guns. Typically, positions on the ship measured range and bearing of the target; these instantaneous measurements are used to calculate rate of change values, and the computer ("fire control table" in Royal Navy terms) then predicts the correct firing solution, taking into account other parameters, such as wind direction, air temperature, and ballistic factors for the guns. The British Royal Navy widely deployed the Pollen and Dreyer Fire Control Tables during the First World War, while in World War II a widely used computer in the US Navy was the electro-mec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Servomotor
A servomotor (or servo motor or simply servo) is a rotary or linear actuator that allows for precise control of angular or linear position, velocity, and acceleration in a mechanical system. It constitutes part of a servomechanism, and consists of a suitable motor coupled to a sensor for position feedback and a controller (often a dedicated module designed specifically for servomotors). Servomotors are not a specific class of motor, although the term ''servomotor'' is often used to refer to a motor suitable for use in a closed-loop control system. Servomotors are used in applications such as robotics, CNC machinery, and automated manufacturing. Mechanism A servomotor is a closed-loop servomechanism that uses position feedback (either linear or rotational position) to control its motion and final position. The input to its control is a signal (either analog or digital) representing the desired position of the output shaft. The motor is paired with some type of positio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flywheel
A flywheel is a mechanical device that uses the conservation of angular momentum to store rotational energy, a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, assuming the flywheel's moment of inertia is constant (i.e., a flywheel with fixed mass and second moment of area revolving about some fixed axis) then the stored (rotational) energy is directly associated with the square of its rotational speed. Since a flywheel serves to store mechanical energy for later use, it is natural to consider it as a kinetic energy analogue of an electrical Inductor. Once suitably abstracted, this shared principle of energy storage is described in the generalized concept of an accumulator. As with other types of accumulators, a flywheel inherently smooths sufficiently small deviations in the power output of a system, thereby effectively playing the role of a low-pass filter with respect to the mechanical veloc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USS Henderson (AP-1)
The first USS ''Henderson'' (AP-1) was a transport in the United States Navy during World War I and World War II. In 1943, she was converted to a hospital ship and commissioned as USS ''Bountiful'' (AH-9). Named for Marine Colonel Archibald Henderson Archibald Henderson (January 21, 1783 – January 6, 1859) was the longest-serving Commandant of the United States Marine Corps, Commandant of the Marine Corps, serving from 1820 to 1859. His name is learned by all recruits at United States Mari ..., she was launched by Philadelphia Navy Yard on 17 June 1916; sponsored by Miss Genevieve W. Taylor, great-granddaughter of General Henderson; and commissioned at Philadelphia, Pennsylvania on 24 May 1917. Service history World War I, 1917–1918 ''Henderson'' arrived New York on 12 June 1917 and sailed two days later with Rear Admiral Albert Gleaves' Cruiser and Transport Force, which carried units of the American Expeditionary Force to France. In her holds she had space for 1,50 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USS Worden (DD-16)
The first USS ''Worden'' (DD-16) was a in the United States Navy. She was named for Admiral John Lorimer Worden. It was the first US ship equipped with a stabilizer. Built in Sparrows Point, Maryland ''Worden'' was laid down at Sparrows Point, Maryland, on 13 November 1899 by the Maryland Steel Company; launched on 15 August 1901; sponsored by Mrs. Daniel F. Worden, the daughter-in-law of Rear Admiral Worden; and commissioned on 17 March 1903. Pre-World War I ''Worden'' passed her final acceptance test on 18 July and began duty with the 2nd Torpedo Flotilla, based at Norfolk, Virginia. For more than four years, she remained a unit of the 2nd Torpedo Flotilla and conducted operations along the eastern seaboard from Maine south to the Caribbean and the Gulf of Mexico. Annually, she participated in the Fleet maneuvers held in the warm waters of the Caribbean. On 18 November 1907, the warship was placed in reserve at the Norfolk Navy Yard. As a unit of the Reserve Torpedo Flotilla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-rolling Gyro
Ship stabilizing gyroscopes are a technology developed in the 19th century and early 20th century and used to stabilize roll motions in ocean-going ships. It lost favor in this application to hydrodynamic roll stabilizer fins because of reduced cost and weight. However, since the 1990s, there is renewed interest in the device for low-speed roll stabilization of vessels (Tohmei, Seakeeper, Quick MC2, etc.). Unlike traditional fins, the gyroscope does not rely on the forward speed of the ship to generate a roll stabilizing moment and therefore can stabilize motor yachts while at anchor. However, the latest generation of "zero speed" fins stabilizers (CMC, Humphree, etc.) can stabilize yachts while at anchor thanks to their eccentricity with respect of the shaft. The World War I transport , completed in 1917, was the first large ship with gyro stabilizers. It had two 25-ton, diameter flywheels mounted near the center of the ship, spun at 1100 rpm by AC motors. The gyroscopes' ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
