Possible Clues:

• Twenty one, certainly not eleven
• Nineteen twelve iceberg victim
• Having huge strength - ship that famously sunk
• A huge loss?
• Article I can't contrive to assimilate, though it's great
• Big, but a little bird I can get confused with
• Huge bird, one in charge
• Huge little bird I can follow to the bottom of the sea
• Great ocean liner sunk by iceberg
• Iceberg-hitting ship