Related Clues:

• Didn't stay up
• Not yet taken care of
• Torpedoed
• Lost altitude
• Dropped like an anchor
• Sunk
• Sent to the bottom
• Set, as the sun
• Destroyed destroyers
• Fell prey to quicksand
• Fell gradually
• Freed from fasteners
• Loosened, as a 57-Down
• Opened, as a necktie
• How a knot may come