unsinkable

My first reaction upon finishing it was to imitate the unsinkable Ursula and begin all over again.

The craft is rude and comfortless in the extreme and so constructed as to be nearly unsinkable if kept off the rocks.

It is unsinkable for one thing, and, being flat-bottomed, slips over the waves instead of plowing through them.

Seal the boat and she's unsinkable the way a corked bottle is.

Also, battleships which should be unsinkable and provided with longer-range guns than those of the enemy would be required.

Any surface ship, to meet fully the submarine menace, must be not only unsinkable, but it must also be indestructible.