Narrative:

En route to destination, airport WX dropped below our landing minimums due to fog. ATC gave us holding instructions at intersection about 30 mi north of destination airport. Fuel burn from holding point to alternate airport was calculated, 45 mins reserve added, and decision time was set. At decision time ATC gave us initial heading and routing to alternate airport. This routing was unexpectedly long and round about, and would have cut into our 45 min reserve. I asked ATC for updated RVR at original destination. RVR was now 2000 ft and aircraft were now landing. I then asked ATC to work out a new route to original destination with no delay vectors and that if he could not do that we would have to get a more direct routing to alternate airport reference our fuel. This was perceived by ATC as a minimum fuel situation and they gave us priority handling to destination airport. We landed at our original destination with 50 mins worth of fuel. In retrospect I should not have waited until I was at minimum fuel before proceeding to my alternate. From now on I will always leave myself an out -- and then some.

Google
 

Original NASA ASRS Text

Title: MINIMUM FUEL SIT WITH COMMUTER FLC BUT NOT CALLED AS SUCH.

Narrative: ENRTE TO DEST, ARPT WX DROPPED BELOW OUR LNDG MINIMUMS DUE TO FOG. ATC GAVE US HOLDING INSTRUCTIONS AT INTXN ABOUT 30 MI N OF DEST ARPT. FUEL BURN FROM HOLDING POINT TO ALTERNATE ARPT WAS CALCULATED, 45 MINS RESERVE ADDED, AND DECISION TIME WAS SET. AT DECISION TIME ATC GAVE US INITIAL HDG AND RTING TO ALTERNATE ARPT. THIS RTING WAS UNEXPECTEDLY LONG AND ROUND ABOUT, AND WOULD HAVE CUT INTO OUR 45 MIN RESERVE. I ASKED ATC FOR UPDATED RVR AT ORIGINAL DEST. RVR WAS NOW 2000 FT AND ACFT WERE NOW LNDG. I THEN ASKED ATC TO WORK OUT A NEW RTE TO ORIGINAL DEST WITH NO DELAY VECTORS AND THAT IF HE COULD NOT DO THAT WE WOULD HAVE TO GET A MORE DIRECT RTING TO ALTERNATE ARPT REF OUR FUEL. THIS WAS PERCEIVED BY ATC AS A MINIMUM FUEL SIT AND THEY GAVE US PRIORITY HANDLING TO DEST ARPT. WE LANDED AT OUR ORIGINAL DEST WITH 50 MINS WORTH OF FUEL. IN RETROSPECT I SHOULD NOT HAVE WAITED UNTIL I WAS AT MINIMUM FUEL BEFORE PROCEEDING TO MY ALTERNATE. FROM NOW ON I WILL ALWAYS LEAVE MYSELF AN OUT -- AND THEN SOME.

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.