Despite all the time, money and effort that go into the development of aircraft, the history of commercial aviation is littered with devastating, deadly crashes. The investigations that follow such disasters are driven by the need to find out "what went wrong" and prevent whatever did go wrong from happening again. The experts call this "tombstone technology" - big advances in air safety that come about in the aftermath of a catastrophe. From the black box that became standard after accidents in the 1950s to the installation of Doppler radar in response to wind shear accidents in the '80s, this episode tells the stories of accidents that changed the way we fly, the groundbreaking technology that rose from the ashes of disaster and the on-going quest for even greater safety in the skies.

Want to continue exploring this topic? Visit this exhibit at the Detroit Science Center: Doppler Arm - The Doppler Arm is a big rotating arm in the Waves & Vibrations Laboratory. When you press a button, the red ball on the end of the arm produces a tone. When you stand in the middle, the tone seems steady. If you stand off to the side, the pitch seems to rise and fall depending on whether the ball is coming toward you or going away. In conjunction with the Tornado exhibit, this can show how tornadoes are detected.

Tuesday, 1/30/07 from 9-10 p.m. ET