Sea anchor

Early sea anchors were crude devices, but today most take the form of a drogue parachute.

The parachute anchor is designed to be launched from the bow and effectively stop the boat's progress relative to the current in an open sea.

In The Sea-Wolf, author and sailor Jack London described using various broken spars and sails, tied to a line, as an improvised sea anchor.

An 1877 book used by the United States Naval Academy describes methods of making sea anchors.

This is called a trip line, and attaches to the rear of the anchor, allowing it to be pulled in back first, shedding water rather than filling.

Because a high degree of stretch is desirable in this application, a material with a low elastic modulus is preferred, such as nylon.

If there is no concern about breaking waves and the only reason the sea anchor is being used is to reduce drift from the wind, then a short rope may be used.

Under these conditions, a rope as much as 10 to 15 times the length of the hull should be used to provide a high degree of shock absorption.