Narrative:

We were on a trip to ZZZ. We had plenty of fuel plus extra before we left. We were vectored for WX; then rerouted in the middle of flight. Supplemental information from acn 748834: after putting the new route in the FMS and verifying the route the FMS said we did not have enough fuel to get to ZZZ. I spoke with dispatch and they gave me a new burn to ZZZ. It appeared that we would land in ZZZ with 400 pounds of fuel on board. I mistakenly interpreted the minimum fuel call and a fuel emergency as the same. I then declared a fuel emergency and ATC cleared us direct ZZZ and landed without incident with enough fuel on board. In the event of trying to put all the information together I had forgotten that a fuel emergency is when you only have 30 mins of fuel remaining; instead of when you predict you are going to land in that situation.

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Original NASA ASRS Text

Title: EMB-145 FLT WAS GIVEN REROUTE DURING FLT. AFTER ENTERING ROUTE INTO FMS; IT WAS DETERMINED THAT FLT WOULD LAND WITH INSUFFICIENT FUEL; SO THE FLT CREW DECLARED EMER FUEL AND RECEIVED PRIORITY HANDLING.

Narrative: WE WERE ON A TRIP TO ZZZ. WE HAD PLENTY OF FUEL PLUS EXTRA BEFORE WE LEFT. WE WERE VECTORED FOR WX; THEN REROUTED IN THE MIDDLE OF FLT. SUPPLEMENTAL INFO FROM ACN 748834: AFTER PUTTING THE NEW RTE IN THE FMS AND VERIFYING THE RTE THE FMS SAID WE DID NOT HAVE ENOUGH FUEL TO GET TO ZZZ. I SPOKE WITH DISPATCH AND THEY GAVE ME A NEW BURN TO ZZZ. IT APPEARED THAT WE WOULD LAND IN ZZZ WITH 400 LBS OF FUEL ON BOARD. I MISTAKENLY INTERPED THE MINIMUM FUEL CALL AND A FUEL EMER AS THE SAME. I THEN DECLARED A FUEL EMER AND ATC CLRED US DIRECT ZZZ AND LANDED WITHOUT INCIDENT WITH ENOUGH FUEL ON BOARD. IN THE EVENT OF TRYING TO PUT ALL THE INFO TOGETHER I HAD FORGOTTEN THAT A FUEL EMER IS WHEN YOU ONLY HAVE 30 MINS OF FUEL REMAINING; INSTEAD OF WHEN YOU PREDICT YOU ARE GOING TO LAND IN THAT SITUATION.

Data retrieved from NASA's ASRS site as of January 2009 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.