The sabotage of Venture is the attempted assassination of Lena Luthor by assassin-for-hire John Corben, hired by Lena's adoptive brother Lex Luthor. The spacecraft's crashing was prevented in a join effort by Supergirl and Superman.
Hired by Lex Luthor from within his maximum security prison, John Corben tampered with an oscillator used on the spacecraft, which was positioned directly beneath the seat in which Lena Luthor was supposed to sit in; however, she had to cancel at the last minute, leaving her seat empty. As the spacecraft fell to Earth, both Supergirl and Superman saw the report on the news, coming to the aid of the ship in their first joint effort. Superman put out the flaming oscillator, before the two of them moved it at such an angle that the Venture was able to land relatively smoothly.