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jupiter escribió:Pregunta para los expertos.
Que ventajas aporta un timón en X, comparado con un timón tradicional?

jupiter escribió:Pregunta para los expertos.
Que ventajas aporta un timón en X, comparado con un timón tradicional?

Compared with the cross rudder, X-form rudder has the following advantages: Firstly, X-form rudder has the higher rudder efficiency and its manipulate surface area is smaller about 10% than cross rudder, so that submarine could avoid the collision problem when it is landing. Secondly, X-form rudder reduces the serious consequences by rudder-blocked and improves the security and the underwater dynamic unsinkability. Besides, X-form rudder reduces the heeling moment, weight and stern heaviness when cross-rudder submarine turning, and having an advantage 13 2017 3rd International Conference on Computational Systems and Communications (ICCSC 2017) Published by CSP © 2017 the Authors to sail steadily when it is attacked. Finally, X-form rudder reduces interaction between propeller and rudder, and reduces the noise[4].

Most modern military submarines have a hull form that at least approximates an axisymmetric body of revolution. Most of these have four control surfaces at the stern for steering the vessel, that is, for making it turn left or right--the rudder--or rise or dive--diving plane--or a combination of both. In turn, in most modern submarines these control surfaces are in cruciform. That is, the rise-dive surfaces are generally in the same plane as the horizontal plane through the centerline of the vessel, and the turning surfaces are in the same plane as the vertical plane through the centerline. Thus, the control surfaces are generally in the form of a Greek cross.In most cases the two rudder planes are yoked together, and the two diving planes are yoked together. Because of this yoking, each pair of control surfaces is operated by a single actuating rod. Thus, one rod turns the ship, and the other rod causes the ship to rise or dive.It is known that arranging the control surfaces or planes of a submarine in an X configuration has certain advantages. In this form, the control surfaces are in the form of an X. Unlike cruciform designs, X-stern designs utilize all four planes as part of any maneuver. Therefore, an X-stern design enjoys more maneuvering force per unit of control surface area than cruciform designs. X-stern ships can be designed with smaller control surfaces while maintaining maneuvering envelopes comparable to cruciform ships with larger control surfaces. Smaller control surfaces obviously have less drag, but may also be quieter--a very important factor today for a submarine.The submarine USS ALBACORE had an X-stern configuration where the opposite control surfaces were yoked together. Australian submarines of the recent COLLINS class have X-stern configurations, but the control surfaces are not yoked together and each of the four surfaces has its own actuator. These are two examples of the current known methods of actuating X-sterns. In both cases, the control system for the operating rods is more complicated than that aboard a cruciform ship. In a cruciform ship, if the helmsman wants to turn the ship, the control system commands the rudder operating rod to extend or retract. If a change in depth is required, the control system commands the diving operating rod to extend or retract. In both X-stern designs, the control system commands every operating rod to move in one direction or the other, for any maneuver. Controlling these coordinated operating rod movements is a complex task that can be accomplished with a computer. However, manual coordination of the operating rods, in the event of a computer casualty, is difficult. The proven X-rudder configuration was chosen for a high manoeuvrability. The rudders are laid out in a way that they press a preswirl on the propeller inflow which homogenizes the wake flow field and increases the propeller efficiency on the one hand and reduces the noise signature on the other hand. The propelling power is provided by a Skewback propeller whose extremely low rotation speed prevents cavity and which generates thrust silently even at high speeds.

Lepanto escribió:Japón recibe su primer SSK de clase Soryu (SSK) equipado con baterías de iones de litio en una ceremonia celebrada el 5 de marzo en la Prefectura de Hyogo en el centro-oeste de Japón. De nombre JS Oryu (con número de bandera SS 511), el buque de 84 m de eslora fue incluido en la Flotilla Submarina 1 de la marina japonesa con sede en Kure, prefectura de Hiroshima. Fue construido por Mitsubishi Heavy Industries (MHI) en sus instalaciones en Kobe. El Oryu es el undécimo submarino de la clase y el sexto construido por MHI, los otros cinco fueron construidos por Kawasaki Heavy Industries (KHI). La puesta de quilla del Oryu fue en marzo de 2015 y se botó en octubre de 2018.

Lepanto escribió:Japón compra para la Guardia Costera dos Airbus H225, es un nuevo contrato que elevará la flota de la Guardia Costera japonesa de Super Puma a 15 unidades, incluidos dos AS332. El número total de Super Puma en servicio en Japón hoy en diferentes versiones es de 28 aparatos.

https://air-cosmos.com/article/les-gard ... h225-22889