blackhole sci-fi story

hello all,

once i read a short story about a spaceship trapped in a blackhole graviational field which was eventually maneuvered out by exerting different accelerations in apogee and perigee points of its orbit around the vortex.

that was the idea of a brilliant professor which was heading home in the same spaceship and his superb will/love determined to defeat the cosmic monster.

can anyone there help me to find the story, please? since i have forgotten both the title and the author.

thanks a zillion,