Originally Posted by
BRUpax
This thread has got my attention and so I looked up this BAC business. I'm still confused though. From what I'm reading you can still at a certain average weight be deemed as having your skills impaired at 0.03% So why is that set as the limit for pilots? Shouldn't it be even lower? I also note that the table indicates that no matter your weight one is only considered "legally intoxicated" from 0.08 at the very minimum if you weigh 160 pounds.
The .08% number is the one now generally used for motor vehicle operation (the limit for young drivers is often lower). The FAA limits under 14 CFR Part 121 start with mandating "temporary" removal from duty when breath BAC measures .02% on a required test. The 8-hour rule, under 14 CFR Part 91.17, is considered a minimum. The relevant FAA brochure, summarizing the rules, is
here.
Individual states often have their own laws covering alcohol consumption and flying. That's where the .04% reference (Minnesota's law) in the story about the Delta pilot comes from.