The documentary

Air Crash Investigation, (also known as Air Emergency in the U.S)is a documentary television program produced by Cineflix in Canada. It is aired on Discovery Channel Canada and the National Geographic Channel.

This documentary investigates many air crashes in modern history after the introduction of the black box flight recorders. It reveals events that led up to each disaster, the causes of the accidents and the measures recommended in the report by the NTSB or the investigating Commission to prevent a similar incident happening again. It features re-enactments, interviews, testimony, computer-generated imagery, and in some episodes, cockpit voice recordings to reconstruct the sequence of events to the audiences. As of March 2008, five seasons of programs have been produced.

As there are many different names to the series, there is some confusion over the proper name of the series. The program was originally produced in Canada under the name Mayday. However, viewers also refer to this series as Air Crash Investigations while National Geographic Channel does not officially use the final s.

There are small differences to the show as released to different regions. This includes the use of a British narrator, titling, and different theme music. In Australia the first season of the show was aired as Mayday whereas the following seasons were aired as Air Crash Investigation

Furthermore, this program, along with the similar series Blueprint for Disaster, for a time were typically billed together as Disaster Detectives on Discovery Channel Canada. It consisted of a short 10-second clip of various scenes aired before the show.

(From http://www.wikipedia.org/)