How are gripes used in relation to lifeboats?

Gripes play a crucial role in securing the lifeboat to its cradle on the ship. Their primary function is to hold the lifeboat in place while the vessel is at sea, ensuring that the lifeboat does not come loose during normal operations or in rough weather conditions. This secure attachment is vital for safety, as it prevents the potential hazards of the lifeboat becoming dislodged unintentionally.

The other options address different aspects of lifeboat operation and safety but do not accurately describe the specific role of gripes. For instance, while safety lines are critical for crew movement and safety aboard the lifeboat, they serve a different purpose than gripes. Additionally, launching the lifeboat involves other mechanisms and procedures, such as the use of tackle and davits. Gripes do not directly assist in the launching process. Finally, while stability is essential for a lifeboat, preventing tilting involves proper design and weight distribution rather than the function of gripes, which are primarily focused on securing the lifeboat in its storage position.