Captain of a DC9 took off below published WX minimums.

Attributes
ACN	429504
Time
Date	199902
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : dtw.airport
State Reference	MI
Altitude	agl single value : 0
Environment
Flight Conditions	IMC
Weather Elements	Fog
Light	Dawn
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tower : dtw.tower
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	ground : holding
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 120 flight time total : 11600 flight time type : 6000
ASRS Report	429504
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : multi engine pilot : commercial
Events
Anomaly	non adherence : far non adherence : published procedure
Independent Detector	other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact
Supplementary
Problem Areas	Weather Flight Crew Human Performance
Primary Problem	Weather
Air Traffic Incident	Pilot Deviation

Narrative:

Takeoff minimums for runway 3L are 600/600/600 ft for approach, midfield, rollout RVR's respectively. ATIS reported RVR 3000 variable 700 ft. At beginning of taxi, RVR's were reported as 2000/700/700 ft. During taxi mid and rollout RVR varied considerably. Last heard RVR report prior to takeoff clearance was 3000/700/600 ft as I recall. After liftoff in response to another aircraft's question, the mid and/or rollout RVR was reported as 500 ft. I may have taken off with 1 or more RVR's less than required.

Original NASA ASRS Text

Title: CAPT OF A DC9 TOOK OFF BELOW PUBLISHED WX MINIMUMS.

Narrative: TKOF MINIMUMS FOR RWY 3L ARE 600/600/600 FT FOR APCH, MIDFIELD, ROLLOUT RVR'S RESPECTIVELY. ATIS RPTED RVR 3000 VARIABLE 700 FT. AT BEGINNING OF TAXI, RVR'S WERE RPTED AS 2000/700/700 FT. DURING TAXI MID AND ROLLOUT RVR VARIED CONSIDERABLY. LAST HEARD RVR RPT PRIOR TO TKOF CLRNC WAS 3000/700/600 FT AS I RECALL. AFTER LIFTOFF IN RESPONSE TO ANOTHER ACFT'S QUESTION, THE MID AND/OR ROLLOUT RVR WAS RPTED AS 500 FT. I MAY HAVE TAKEN OFF WITH 1 OR MORE RVR'S LESS THAN REQUIRED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.