Narrative:

We were told to hold for runway change in ZZZ1. Given initially 10 min delay; then told we would not get in for 30+ mins. Fuel at the time of our divert to ZZZ2 was 6.0. Mcdu showed us arriving in ZZZ2 with 2.8 which is less than 30 mins of fuel. An emergency was declared for fuel. Arrived with 3.7. Refueled. Uneventful afterwards.

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Original NASA ASRS Text

Title: A320 FLT CREW DECLARES FUEL EMER DUE TO DELAYS AT DEST. DIVERSION TO ALTERNATE RESULTS IN LNDG WITH MINIMUM FUEL.

Narrative: WE WERE TOLD TO HOLD FOR RWY CHANGE IN ZZZ1. GIVEN INITIALLY 10 MIN DELAY; THEN TOLD WE WOULD NOT GET IN FOR 30+ MINS. FUEL AT THE TIME OF OUR DIVERT TO ZZZ2 WAS 6.0. MCDU SHOWED US ARRIVING IN ZZZ2 WITH 2.8 WHICH IS LESS THAN 30 MINS OF FUEL. AN EMER WAS DECLARED FOR FUEL. ARRIVED WITH 3.7. REFUELED. UNEVENTFUL AFTERWARDS.

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.