Shuttlecock

A shuttlecock (also called a bird or birdie) is a high-drag projectile used in the sport of badminton. The name is from the Victorian times, when Badminton was first discovered and became popular. It has an open conical shape: the cone is formed from 16 or so overlapping feathers, usually goose or duck, embedded into a rounded cork base. The cork is covered with thin leather. To ensure that shuttlecocks rotate consistently, only feathers from the birds' left wings are used. The shuttlecock's shape makes it extremely aerodynamically stable. Regardless of initial orientation, it will turn to fly cork first, and remain in the cork-first orientation. The name shuttlecock is frequently shortened to shuttle. The "shuttle" part of the name was probably derived from its back-and-forth motion during the game, resembling the shuttle of a loom; the "cock" part of the name was probably derived from the resemblance of the feathers to those on a cockerel.

The feathers are brittle; shuttlecocks break easily and often need to be replaced several times during a game. For this reason, synthetic shuttlecocks have been developed that replace the feathers with a plastic skirt. Players often refer to synthetic shuttlecocks as plastics and feathered shuttlecocks as feathers.

Feather shuttles need to be properly humidified for at least 4 hours prior to play in order to fly the correct distance at the proper speed and to last longer. Properly humidified feathers flex during play, enhancing the shuttle's speed change and durability. Dry feathers are brittle and break easily, causing the shuttle to wobble. Saturated feathers are 'mushy', making the feather cone narrow too much when strongly hit, which causes the shuttle to fly overly far and fast. Humidification boxes are often used, but a simple moist sponge inserted in the feather end of the closed shuttle tube will work nicely. Water should never touch the cork of the shuttle. Shuttles are tested prior to play to make sure they fly true and at the proper speed, and cover the proper distance. Different weights of shuttles are used to compensate for local atmospheric conditions. Both humidity and height above sea level affect shuttle flight. A proper shuttle will generally travel from the back line of the court to just short of the long doubles service line on the opposite side of the net, with a full underhand hit from an average player.

The cost of good quality feathers is similar to that of good quality plastics, but plastics are far more durable, typically lasting many matches without any impairment to their flight. Shuttles are easily damaged and should be replaced every three or four games, and sooner if they are damaged and do not fly straight. This interferes with the game, as the impairment on the flight of the shuttle may misdirect the direction of the shuttlecock.

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