PILOT ARRESTED FOR BEING DRUNK BEFORE FLIGHT
California police arrested an Aloha Airlines co-pilot for allegedly being drunk as he tried to enter a plane to fly it from Oakland, Calif., to Hawaii Saturday...
...The FAA said a breath test indicated the pilot had a blood alcohol level of .18. The legal limit for pilots is .04. That means he was more than four times the legal limit.

The legal BAC for pilots is .04? WHY ISN'T IT ZERO? Why do pilots need to drink before flying?