[Tennessee_Bob]

From http://www.whittsflying.com/Pa ge7Statistics.htm#BM_ach_

Alcohol
1.In accidents from '78 to '87 6% of G.A. pilots had blood alcohol level of at least .04% by weight. 670 people were killed in these accidents.
2. NO 1997 alcohol related accidents.

I ran a search for positive % alcohol on the http://www.ntsb.gov/ntsb/query .asp aviation database. This would pop up any accident report with the word "positive" and "alcohol" in the same sentence. This yielded 26 records. Three records pointed to alcohol as a factor in the crash, two pointed to drugs (marihuana (their spelling), ephedrine, cocaine, psuedoephedrine and more), one pointed to alcohol and drugs. The remainder of the reports that were pulled were listed as reporting that the pilot/crew were not positive for alcohol.

[_Jim]

Studies of how alcohol affects pilot performance

o Pilots have shown impairment in their ability to fly an ILS approach or to fly IFR, and even to perform routine VFR flight tasks while under the influence of alcohol, regardless of individual flying experience.

o The number of serious errors committed by pilots dramatically increases at or above concentrations of 0.04% blood alcohol. This is not to say that problems don't occur below this value. Some studies have shown decrements in pilot performance with blood alcohol concentrations as low as the 0.025%.

Year          General      Pilots with       Piots with     
             Aviation          BAC               BAC        
               Pilot           of                of        
            Fatilities    0.02% or more*   0.04% or more *  

1987            341            13.5%             8.5%       

1988            364            6.6%              6.3%       

1989            349            12.9%             8.0%       

1990            367            14.2%             7.9%       

1991            379            12.9%             7.9%       

1992            396            11.9%             7.3%       

1993            338            12.7%             8.9%       

*Some cases may include alcohol produced after death by tissue decomposition.
BAC= Blood alcohol concentration

Excerpted from here.

[dighton]

Thank you for the links, Tennessee Bob and _Jim.

For those seeking reassurance, one sentence stands out here:

No pilot in a CFR Part 121 (Air Carrier) fatal aviation accident was found to be positive for drugs or alcohol.

Those out for some moments of terror, look here:

Five years ago, Southwest’s Capt. Gary Higby had to save another Boeing 737 on approach to the Oakland, Calif., airport when his co-pilot, who was at the controls for the night-time descent in low visibility, let out a “curdling scream’’ and froze in his seat, Higby recalled. The co-pilot jammed on the right rudder and the jetliner, barely 900 feet above ground, responded with a 35-degree roll. Unable to push on the left rudder because his co-pilot was in a “catatonic rigid state,’’ Higby said he was able to retrieve a level flight only by increasing the thrust on the right engine. He landed the aircraft after flight attendants finally pried the co-pilot from the seat and dragged him to the galley.

Higby said that doctors at the hospital where the copilot was rushed after landing concluded that the second-in-command was an alcoholic who had experienced delirium tremens during the landing. Later, Higby said, the airline discovered that he had had four arrests for drunken driving and had admitted to being a binge drinker.