Sunday, August 27, 2006

Lexington Comair crash

Despite the stress and strain of 9/11 and terrorism concerns, U.S. commercial aviation has at least enjoyed a remarkably safe period of operations these past four and a half years.

The crash of a Comair regional jet near Lexington, Kentucky this morning was the worst since the American flight 587 crash in 2001.

Early speculation is almost always risky, sometimes including statements from official sources:
There were no reports of bad weather in the Lexington area. "It was dark at the time of the accident, but it was clear," Brown said.
That depends on what you consider clear. Using simple open source information from the web and a little personal knowledge, we can prove it wasn't 'clear'. Here's the official weather around the time of crash:
KLEX 270954Z 20007KT 8SM FEW090 SCT120 24/19 A3000 RMK AO2 SLP147 T02390194
What that mess means:
Time-- 0954 Greenwich Mean Time, or 5:54 AM EDT.
Sky -- a few scattered clouds at 9,000 and 12,000 feet above ground
Wind-- from the southwest (200 degrees) at 7 knots (8 mph).

Technically not clear. Matter of fact, the subsequent weather report shines more light on the notion it wasn't clear:
KLEX 271054Z 22008KT 8SM FEW047 BKN060 OVC090 23/20 A3002 RMK AO2 RAB12E51 SLP154 P0001 T02330200

Time-- 6:54 AM EDT
Sky -- scattered to broken clouds from 4,700 to 6,000 feet, overcast at 9,000 feet (in other words, cloudy).
Wind-- similar to the past hour, southwest at 9 mph.

The key term in this report was "RAB12E51". This means rain began falling at 12 minutes past the top of the hour, or 6:12 AM EDT, and ended at 6:51 AM EDT. The "P0001" means only 0.01 inches of rain was recorded, just a sprinkle, but certainly not 'clear'.

The plane was cleared for takeoff at 6:05 AM EDT, therefore the first weather report should have been read to the crew by the tower, supposedly staffed 24/7. The plane crash time was 6:19 AM EDT. Keep in mind the "cleared for takeoff" time doesn't mean the plane took off at that time.

Here is a rather crude radar picture from around 6 AM:
It shows a few specks of rainshowers around central Kentucky, nothing too bad, but an indication rain was in the area. This alone doesn't mean weather was a factor in the crash, it just means weather cannot be ruled out.

From looking at the airport diagram above, the 'wrong runway' theory looks plausible, we'll have to see what the NTSB says. The bottom line here is to always be wary of initial statements, even when coming from official sources.

NTSB UPDATE 8/27/06

The NTSB just gave a press conference and indicated (without putting themselves too far out on a limb) that flight 5191 took off from the shorter runway, 8-26. That would take weather out of the list of probable causes, and sets up a face-off between what the controller said and what the pilots heard, along with airport functions (runway lights, etc) and pilot rest factors. Lots of lawsuits.

SPEAKING OF LAWSUITS... 8/29/06

Not one single legal writ will bring one single person back, but it may prevent the same thing from happening again. CNN has unearthed an FAA policy requiring the presense of two controllers in the tower, when there was in fact only one. In perusing the story it's clear the FAA union is prepared to use this to their advantage, and lawyers will soon follow.

But in reality, the pilot-in-command is always responsible for the safe operation of the aircraft. He was cleared on 22, took off on 26 despite noticing there were no lights, and caused the crash. Neither controllers, nor asphalt contractors, nor airport managers were sitting in that cockpit.

POLL 9/7/06

This poll on the Avweb site seems to define the impression of pilots as to fault.

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