On this day in 1970, Apollo 13 crew members John Swigert Jr. and James Lovell reported a major technical fault to Houston. While the movie popularized "Houston, we have a problem," the actual exchange used the past tense. After a massive electrical failure in an oxygen tank, the real intreaction was: Swigert: "Okay, Houston, we've had a problem here." Houston: "This is Houston. Say again please." Lovell: "Houston, we've had a problem. We've had a main B bus undervolt."