sheet
A sheet ( nautical , derived from lap meaning "corner, tip" of a sail ) is a line for operating a sail when sailing . Sheets are part of the running goods of sailing ships and sailing boats .
In the case of Schratsails (sails that are attached in the longitudinal direction of the ship), sheets are required to align the sails and to trim them . Above all, they control the angle of attack of the sails to the wind.
In square sails (square sails, which are held up of a cross piece and transversely moved in front of the mast) each hold two pods, the sides of the fixed top of the Rah sail down. They are used on square sails, under which there is another yard, for setting and lifting the sail as a counterpart to the geitauen ; the angle of attack of the sail is only changed here by bream . In Under sail (the lowest square sails on a mast, z. B. Fock ) or the forecourse affect the pods also the orientation of the sail.
“ Broken mast and sheet ” is the name of a blessing for seafarers.
Designations
Since there are usually several sheets on a sailing ship or boat, they always bear the name of the sail to which they are attached; for the mainsail , for example, it is called the mainsheet , for the jib Jib sheet . If two sheets are attached to a sail, they are more precisely referred to as port sheet or starboard sheet according to the side of the ship . B. Jib port sheet. In the case of a spinnaker , which is driven with two lines on the side, the line in leeward direction is called the spinnaker sheet , the line in windward direction is called the eighth hauler . The corner of the sail to which the sheet is attached is called the clew .
Dinghies and yachts
service
In order to pull the sails closer to the center of the ship, depending on the course to the wind , or to trim them flatter, a sheet must be “pulled in” or “pulled tight” (pulled); In order to open the sails further on a spacer sheet course or to reduce their tension, they are "lowered" (line released).
Depending on the size of the sail, the wind can exert great forces on the sheet that can no longer be handled with the bare hand. Is on a sheet the Boom mounted, as is usually the mainsail of yachts and dinghies , it is therefore a pulley , a " tackle , served". The translation starts with a double - z. B. with the laser - and can go up to a sevenfold deflection, with 3 upper and 4 lower rollers. These are used on smaller yachts. After that, this system becomes impractical because the blocks required become too bulky and the friction becomes too great, which is why the mainsheet is placed on one or two winches and operated with it on larger yachts . Regatta yachts occasionally also have two independent tackles, one for coarse adjustment with winches and one for fine trimming using an actual pulley system.
The lower end of the main bulkhead is attached to dinghies on the cockpit floor and is operated by the helmsman . On regatta ships and yachts, the lower lanyard block is slidably attached to a traveler rail. The sheet of a foresail is guided past the mast on both sides through rollers and guide eyes into the cockpit of the ship, where the bow is responsible for it. On larger boats, winches are used, which can transmit a large tractive force thanks to their mechanical transmission.
Since the position of the pods, especially on sports boats, often has to be changed depending on the course and wind strength, comb and curry clips enable quick operation. The sheet is only locked in the short term in them and does not need time-consuming on a cleat occupied or detached from her. On smaller dinghies, small winches called “creaking bollards” are used for this purpose. They can only be turned in one direction and hold the sheet in its current position by friction.
Trim options
Headsail
In order to adjust the position of the foresail, sheets on yachts are almost always guided over a sliding roller on jib sheet guide rails, which are located on both sides of the ship's deck. The point at which the sheet is deflected over a roller is known as the pick-up point . Its shift is not only used to adapt to headsails of different sizes, but also to optimize the sail trim. If the haul point is further forward, the leech of the sail is stretched (tightened) more, the deepest curvature of the sail moves backwards and downwards, the twist of the sail decreases and the sail twist is reduced. If the haul point is further back, the bottom leech of the sail is stretched (tightened) and the deepest curve of the sail moves forwards and upwards, the twist of the sail increases and the twist increases. The sheet tension controls the angle of attack of the sail.
Mainsail
The so-called Traveler serves a similar purpose . This involves a sheet deflection on a slide that is movably mounted on a slide rail. With it the fetch point can be moved to windward or leeward. The traveler controls the angle of attack of the sail. The Schotspannung used to control the twist ( twist ) of the sail: the stronger the Schotspannung, the lower is the distortion.
Material and manufacture
Several requirements are placed on the material of pods:
- The line should be as easy to grip as possible and easy to handle (“leaning”).
- Since the line is moved frequently and "rubs" against winches, clamps, etc., it should be as abrasion-resistant as possible.
Today pods are usually made of synthetic fibers, mostly polyester (inexpensive, but has a lot of stretching) or Dyneema , which is significantly more expensive, but also stronger and less stretchable. Lines made of natural fibers are only used on traditional sailors.
Nowadays only braided cordage is used for pods on small boats .
See also
literature
- Ramon Gliewe (Red.): Seamanship. Yachting manual. 22nd edition. Delius Klasing, Bielefeld 1991, ISBN 3-7688-0523-9 .
Individual evidence
- ↑ Wolfgang Pfeifer (Ltg.): Etymological dictionary of German. 6th edition. dtv, Munich 2003, ISBN 3-05-000626-9 , p. 1239 (keyword Schot )