The nuclear storm drive was a type of engine that used nuclear power to drive a starship.
A storm drive was the power source of the spaceship Titanic. Without the power of the storm drive, the ship would cease to function. In close proximity to a planet, for instance Earth, the planet's gravity could pull the ship to crash onto the surface. The effect could be disastrous, as it could wipe out all life on the planet. (TV: Voyage of the Damned)