Originally Posted by
RobertS975
The CVR transcript of the Comair tragedy will give more support to the notion of "confirmation bias" as the cause of this accident. Not even the slightest hesitation that they were accelerating down the intended runway...
And, not a single word of discussion in that 30 minutes on the CVR that the taxiway or runway lights were out - from which I'd guess they had already discussed this and the FO had shared his observation from Friday evening that the Northeast end of runway 22 had no lights working at all. The only time the subject comes up again is mid-roll, after crossing the real 22, when the FO says "dat wierd with no lights" and the Captain says "yeah." That's not proof, but it's the first point at which reality differed from his mental model, and it's the first point a comment is made.
Another framing issue was their delight that they had a very simple clearance that couldn't get "any easier that that", lessening vigilence more.
But there is still the factor of the wrong airport diagram, which is still wrong. (
http://www.naco.faa.gov/d-tpp/0701/00697AD.PDF for those who don't have charts.) The taxiway they should have been using, just west of Alpha-7, is not shown. (it's visible in the photo on wikipedia, at
http://en.wikipedia.org/wiki/Comair_Flight_5191 )
Here's one possible scenario for a different type of framing. The crew understood that A7 was going to be blocked, and got the news that the next best taxiway was in use. Whoever told them that (suppose) meant the new one, the one not shown. They looked at their charts and figured that must mean Alpha-6. They expect an intersection with no lights, no pavement markings, no signage, and four possible ways to go. They expect to see across from them 2 concrete taxiways and, to their extreme left, runway 22, which they expect to be 150 feet wide and have no lights. There is no other spot on that diagram with two concrete taxiways across from them.
But there is a place in reality with two concrete taxiways and a 150 foot wide unlit runway to their extreme left, which is where they really were.
They didn't know about the new taxiway, and they may not have realized that runway 22 was actually 150 feet wide (with only 75 usable).
So, again, nothing seemed out of place, and the decision was "really easy" - taxi to the unlit runway intersection and take the extreme left 150 foot wide runway - "impossible" to make a mistake.
It would be valuable to know what combination of barricades and signage was visible from their gate to the taxiway they took.