GA small aircraft completed approach landing when WX was reported below RVR minimums for landing.

Attributes
ACN	133990
Time
Date	199001
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : smf
State Reference	CA
Altitude	agl bound lower : 0 agl bound upper : 200
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : smf
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	descent : approach landing other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : commercial pilot : instrument
Experience	flight time last 90 days : 35 flight time total : 3200
ASRS Report	133990
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Events
Anomaly	non adherence : published procedure
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other

Narrative:

I was on the ILS 16R approach at smf, flying part 91 on my way to a business meeting. I decided to fly the approach to the decision ht to see how the airport runway environment looked. At decision ht, I was still in VFR conditions on the top of a thin fog layer. I could also see the entire runway approach system, the threshold lights and at least 2000' of the runway, so I completed the landing and proceeded west/O incident. Then a friend told me that the RVR minimum takes priority over the pilot's visibility assessment of the WX conditions. RVR was reported as 1000 (approach) - 1200 (mid) - 1500 (rollout), and minimum on the approach is 1800'. I believe my confusion arose from always being taught that while part 91, I could look at the situation for myself and decide how safe it was. Also, I believe that the tower should not authorize a complete landing if they feel the airport is closed (they didn't say 'closed). Also, they must have given me at least 4 reports of 3 different ranges of RVR--all the while shooting the ILS. Pilots tend to tune this out and concentrate on the approach.

Original NASA ASRS Text

Title: GA SMA COMPLETED APCH LNDG WHEN WX WAS REPORTED BELOW RVR MINIMUMS FOR LNDG.

Narrative: I WAS ON THE ILS 16R APCH AT SMF, FLYING PART 91 ON MY WAY TO A BUSINESS MEETING. I DECIDED TO FLY THE APCH TO THE DECISION HT TO SEE HOW THE ARPT RWY ENVIRONMENT LOOKED. AT DECISION HT, I WAS STILL IN VFR CONDITIONS ON THE TOP OF A THIN FOG LAYER. I COULD ALSO SEE THE ENTIRE RWY APCH SYS, THE THRESHOLD LIGHTS AND AT LEAST 2000' OF THE RWY, SO I COMPLETED THE LNDG AND PROCEEDED W/O INCIDENT. THEN A FRIEND TOLD ME THAT THE RVR MINIMUM TAKES PRIORITY OVER THE PLT'S VIS ASSESSMENT OF THE WX CONDITIONS. RVR WAS RPTED AS 1000 (APCH) - 1200 (MID) - 1500 (ROLLOUT), AND MINIMUM ON THE APCH IS 1800'. I BELIEVE MY CONFUSION AROSE FROM ALWAYS BEING TAUGHT THAT WHILE PART 91, I COULD LOOK AT THE SITUATION FOR MYSELF AND DECIDE HOW SAFE IT WAS. ALSO, I BELIEVE THAT THE TWR SHOULD NOT AUTHORIZE A COMPLETE LNDG IF THEY FEEL THE ARPT IS CLOSED (THEY DIDN'T SAY 'CLOSED). ALSO, THEY MUST HAVE GIVEN ME AT LEAST 4 RPTS OF 3 DIFFERENT RANGES OF RVR--ALL THE WHILE SHOOTING THE ILS. PLTS TEND TO TUNE THIS OUT AND CONCENTRATE ON THE APCH.

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.