Lying a-hull is a heavy-weather survival technique where a sailing vessel drops all sails and lashes the helm to leeward (away from the wind). The boat drifts sideways, typically beam-on to the waves, relying on its own structural resistance to minimize movement and survive extreme storm conditions.

Key aspects of lying a-hull include:
Purpose: Used when sailing is impossible, unsafe, or inefficient, designed to let the vessel ride out a severe storm with minimal crew intervention.

Technique: All sails are furled, and the tiller or wheel is secured to force the bow into the wind; however, the boat will likely sit with its side to the waves.

Risks: While intended for safety, it is considered controversial in extreme conditions, as the boat may be rolled by large, breaking waves.

Alternatives: Modern alternatives often include running with the storm using a sea anchor or storm jib for more control.