A tiny rounding bug in the Patriot’s tracking math accumulated into a timing drift and a missed intercept that killed 28 U.S. soldiers and wounded more than a hundred. The patch existed but wasn’t applied in time — a tragic, avoidable failure.

Sometimes referred to as “the worst bug ever”, this sloppy coincidence of blindly trusting legacy code, reckless type conversion and lacking of error handling mechanism, made the maiden flight of the Ariane-5 a disaster.
The lessons from that failure changed the way we engineer SW today.

Severe bugs might be lethal.
One (or, in fact, two) horrifying example is the crash cases of two Boeing-737 due to bugs in the flying systems.

Did you know?
The Swiss trains are not allowed to have 256 axels!
If that number rings a bell, you are completely right…