Antonyms for the phrase "runs aground" could be "sails smoothly," "navigates safely," or "succeeds." These terms evoke a sense of ease, smoothness, and accomplishment, rather than the struggle and difficulty associated with running aground. They suggest a journey that is without obstacles, challenges, or setbacks. On the other hand, "runs aground" implies a ship or vessel coming to a halt and getting stuck on the ground due to shallow water or underwater obstacles, which can cause damage and delay. Therefore, it's important to consider antonyms that counter this negative connotation with their positive undertone.