In sailing, lying ahull is a controversial method of weathering a storm, executed by downing all

sail A sail is a tensile structure—which is made from fabric or other membrane materials—that uses wind power to propel sailing craft, including sailing ships, sailboats, windsurfers, ice boats, and even sail-powered land vehicles. Sails may ...

s, battening the hatches and locking the

tiller A tiller or till is a lever used to steer a vehicle. The mechanism is primarily used in watercraft, where it is attached to an outboard motor, rudder post or stock to provide leverage in the form of torque for the helmsman to turn the rudder. ...

leeward Windward () and leeward () are terms used to describe the direction of the wind. Windward is ''upwind'' from the point of reference, i.e. towards the direction from which the wind is coming; leeward is ''downwind'' from the point of reference ...

so the boat tries to point to

windward Windward () and leeward () are terms used to describe the direction of the wind. Windward is ''upwind'' from the point of reference, i.e. towards the direction from which the wind is coming; leeward is ''downwind'' from the point of reference ...

but this is balanced by the force of wind and waves. A

sea anchor A sea anchor (also known as a parachute anchor, drift anchor, drift sock, para-anchor or boat brake) is a device that is streamed from a boat in heavy weather. Its purpose is to stabilize the vessel and to limit progress through the water. ...

is not used, allowing the boat to drift freely, completely at the mercy of the storm. Ideally the boat should rest with the wind just forward of the beam so the boat is not broadside onto the waves. Modern boats with

fin keel The fin keel is a stationary foil positioned amidships and projecting downwards under the hull of a sailing vessel. A fin keel is relatively short in a fore-aft direction, and relatively deep, located near the center of the boat. A fin keel is a fi ...

s may have too much windage at the bows for this technique and come to rest broadside on or may not be stable at all.

Sources

Heaving-to: Heavy weather sailing, 1990, by George Day, Blue Water Sailing, archived 2006
Nautical terminology {{sailing-stub