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A tiller or till is a lever attached to a rudder post (American terminology) or rudder stock (English terminology) of a boat that provides leverage in the form of torque for the helmsman to turn the rudder. The tiller can be used by the helmsman directly pulling or pushing it, but it may also be moved remotely using tiller lines or a ship's wheel. Rapid or excessive movement of the tiller results in an increase in drag and will result in braking or slowing the boat. In steering a boat, the tiller is always moved in the direction opposite of which the bow of the boat is to move. If the tiller is moved to port side (left), the bow will turn to starboard (right). If the tiller is moved to starboard (right), the bow will turn port (left). Sailing students often learn the alliterative phrase "Tiller Towards Trouble" to remind them of how to steer. ==Tiller orders == Until the current international standards were applied in the 1930s, it was common for steering orders on ships to be given as "Tiller Orders", which dictated to which side of the vessel the tiller was to be moved. Since the tiller is forward of the rudder's pivot point, and the rudder aft of it, the tiller's movement is reversed at the rudder, giving the impression that orders were given "the wrong way round". For example, to turn a ship to port (its left side), the helmsman would be given the order "starboard helm" or "''x'' degrees starboard". The ship's tiller was then moved to starboard, turning the rudder to the vessel's port side, producing a turn to port. The opposite convention applied in France (where ''tribord''—starboard—meant turn to starboard), but Austria and Italy kept to the English system. There was no standardization in vessels from Scandinavian countries, where the practice varied from ship to ship. Most French vessels with steering wheels had their steering chains reversed and when under the command of a British pilot this could result in confusion. When large steamships appeared in the late 19th century with telemotors hydraulically connecting the wheel on the bridge to the steering gear at the stern, the practice continued. However the helmsman was now no longer directly controlling the tiller, and the ship's wheel was simply turned in the desired direction (turn the wheel to port and the ship will go to port). Tiller Orders remained however: although many maritime nations had abandoned the convention by the end of the 19th century, Britain retained it until 1933〔(Merchant Shipping (Safety and Load Line Conventions) Act 1932, Section 29: "Method of giving helm orders" )〕 and the U.S. merchant marine until 1935.〔 One of the reasons for this system continuing, apart from it being a long-established maritime tradition, was that it provided consistency—regardless of whether a vessel was steered directly by the tiller or remotely by a wheel every vessel had a tiller of some sort and so a tiller order remained true for any vessel. During the transition period the wording of the order was changed, to specify "Wheel to starboard" or "Wheel to port". A well-known and often-depicted example occurred on the RMS Titanic in 1912 just before she collided with an iceberg. When the iceberg appeared directly in front of the ship, her officer-of-the-watch, First Officer William Murdoch, decided to attempt to clear the iceberg by swinging the ship to its port side. He ordered 'Hard-a-Starboard', which was a Tiller Order directing the helmsman to turn the wheel to port (anti-clockwise) as far as it would go. The Titanic's steering gear then pushed the tiller toward the starboard side of the ship, swinging the rudder over to port and causing the vessel to turn to port. These actions are faithfully portrayed in the 1997 film of the disaster. Although frequently described as an error, the order was given and executed correctly— the vessel struck the iceberg anyway. Although this system seems confusing and contradictory today, to generations of sailors trained on sailing vessels with tiller steering it seemed perfectly logical and was understood by all seafarers. Only when new generations of sailors trained on ships with wheel-and-tiller steering came into the industry was the system replaced. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Tiller」の詳細全文を読む スポンサード リンク
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