If you want a reminder of what went wrong on 4 June 1996, when Ariane 5’s
maiden voyage ended in a splendid fireworks display 30 seconds after liftoff,
ESA is not too embarrassed to oblige on
http://www.esrin.esa.it/tidc/Press/Press96/ariane5rep.html.
For a Quicktime movie of the explosion along with
the original stories, CNN’s site at
http://cnn.com/ WORLD/9606/04/rocket.explode/
is the place to go.

An annotated version of a report with even more detail about the crash, is at
http://www.cs.rdg.ac.uk/cs/people/jpb/teaching/ethics/ariane5anot.html.
Finally, if you want a more personal explanation, see software engineer Bob
Baber’s pages at http://www.cs.wits.ac. za/ ~bob/ariane5.htm.