Air carrier crew departs rsw, fl, with less than the authority/authorized visibility reported.

Attributes
ACN	480430
Time
Date	200007
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : rsw.airport
State Reference	FL
Altitude	agl single value : 0
Environment
Flight Conditions	IMC
Weather Elements	Fog
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	MD-80 Series (DC-9-80) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll ground : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 215 flight time total : 22000 flight time type : 5000
ASRS Report	480430
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Events
Anomaly	inflight encounter : weather non adherence : far non adherence : published procedure non adherence : company policies
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Supplementary
Problem Areas	Weather Chart Or Publication Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

While taxiing for takeoff at rsw, local tower reported visibility as '1 mi,' then later '1/4 mi.' I recall RVR for runway in use being reported as 1600 ft, 1200 ft and 1400 ft at various times during taxi. I discussed reduced visibility minimums with first officer and we both agreed that with runway markings we could take off with 600 ft RVR at touchdown, midpoint and rollout. This was in error. For some reason we overlooked the requirement for centerline lights if RVR was less than 1600 ft. I believe I lulled myself into being careless because: 1) the WX was good VFR during the boarding process, 2) fog rolled in at sunrise -- the terminal/gate was still VFR when the tower visibility became 1/4 mi, 3) I'm more accustomed to runways with centerline lights, 4) the visibility did not seem ominous, with patches of better visibility and good alignment using only the painted runway markings, 5) it had been a while since anything similar had happened.

Original NASA ASRS Text

Title: ACR CREW DEPARTS RSW, FL, WITH LESS THAN THE AUTH VISIBILITY RPTED.

Narrative: WHILE TAXIING FOR TKOF AT RSW, LCL TWR RPTED VISIBILITY AS '1 MI,' THEN LATER '1/4 MI.' I RECALL RVR FOR RWY IN USE BEING RPTED AS 1600 FT, 1200 FT AND 1400 FT AT VARIOUS TIMES DURING TAXI. I DISCUSSED REDUCED VISIBILITY MINIMUMS WITH FO AND WE BOTH AGREED THAT WITH RWY MARKINGS WE COULD TAKE OFF WITH 600 FT RVR AT TOUCHDOWN, MIDPOINT AND ROLLOUT. THIS WAS IN ERROR. FOR SOME REASON WE OVERLOOKED THE REQUIREMENT FOR CTRLINE LIGHTS IF RVR WAS LESS THAN 1600 FT. I BELIEVE I LULLED MYSELF INTO BEING CARELESS BECAUSE: 1) THE WX WAS GOOD VFR DURING THE BOARDING PROCESS, 2) FOG ROLLED IN AT SUNRISE -- THE TERMINAL/GATE WAS STILL VFR WHEN THE TWR VISIBILITY BECAME 1/4 MI, 3) I'M MORE ACCUSTOMED TO RWYS WITH CTRLINE LIGHTS, 4) THE VISIBILITY DID NOT SEEM OMINOUS, WITH PATCHES OF BETTER VISIBILITY AND GOOD ALIGNMENT USING ONLY THE PAINTED RWY MARKINGS, 5) IT HAD BEEN A WHILE SINCE ANYTHING SIMILAR HAD HAPPENED.

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.