As a NASA Flight Director for Gemini, Apollo and Space Shuttle missions, Gene Kranz is best known for directing his team in the successful return of the Apollo 13 flight crew after their service module was crippled by an explosion in April 1970. During three tense days, with the eyes of the world upon him, Kranz, wearing his signature white vest, demonstrated leadership and ingenuity that contributed to the safe return of the crew.  His book, Failure is Not an Option, became a best seller.