Narrative:

ATIS at sac metropolitan called for WX at 2000' overcast, 5 mi visibility, ILS out of service, expect NDB runway 16R. We took vectors to NDB final and reported by metre, the final approach fix. At approximately 1000' MSL, still IMC, we asked tower for current WX conditions. Tower advised WX was 700' broken 2 mi visibility in fog. We continued and saw the runway at about 700' MSL and completed a normal landing. On the ground, ground control requested we call them on the land line and gave us the phone number. On the phone, tower controllers told the captain that they thought our company flight operations manual restr us to 1000' and 3 mi for NDB approachs. We checked the manual and found the tower was correct. Although all 3 cockpit crew members knew of a 1000', 3 mi requirement for circling approachs, none of us knew of the requirment for NDB approachs. We suspect a recent change to the manual restr us to the 1000/3 minimums. Contributing factors. The company may have failed to 'point out' or 'highlight' a very important new requirement by just dumping it in a 200 page change. Tower failed to inform us that the WX had deteriorated significantly from that which was being reported by ATIS.

Google
 

Original NASA ASRS Text

Title: ACR LGT OPERATED AND FLEW AN NDB IN CONTRADICTION TO THEIR COMPANY REGS.

Narrative: ATIS AT SAC METRO CALLED FOR WX AT 2000' OVCST, 5 MI VISIBILITY, ILS OUT OF SVC, EXPECT NDB RWY 16R. WE TOOK VECTORS TO NDB FINAL AND RPTED BY METRE, THE FINAL APCH FIX. AT APPROX 1000' MSL, STILL IMC, WE ASKED TWR FOR CURRENT WX CONDITIONS. TWR ADVISED WX WAS 700' BROKEN 2 MI VISIBILITY IN FOG. WE CONTINUED AND SAW THE RWY AT ABOUT 700' MSL AND COMPLETED A NORMAL LNDG. ON THE GND, GND CTL REQUESTED WE CALL THEM ON THE LAND LINE AND GAVE US THE PHONE NUMBER. ON THE PHONE, TWR CTLRS TOLD THE CAPT THAT THEY THOUGHT OUR COMPANY FLT OPS MANUAL RESTR US TO 1000' AND 3 MI FOR NDB APCHS. WE CHKED THE MANUAL AND FOUND THE TWR WAS CORRECT. ALTHOUGH ALL 3 COCKPIT CREW MEMBERS KNEW OF A 1000', 3 MI REQUIREMENT FOR CIRCLING APCHS, NONE OF US KNEW OF THE REQUIRMENT FOR NDB APCHS. WE SUSPECT A RECENT CHANGE TO THE MANUAL RESTR US TO THE 1000/3 MINIMUMS. CONTRIBUTING FACTORS. THE COMPANY MAY HAVE FAILED TO 'POINT OUT' OR 'HIGHLIGHT' A VERY IMPORTANT NEW REQUIREMENT BY JUST DUMPING IT IN A 200 PAGE CHANGE. TWR FAILED TO INFORM US THAT THE WX HAD DETERIORATED SIGNIFICANTLY FROM THAT WHICH WAS BEING RPTED BY ATIS.

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.