Narrative:

Aircraft performance. Aircraft cleared to climb from FL290 to FL330 -- no delay in climb. Suspect the load and weight were incorrect, as I have never seen this performance in 10 yrs on aircraft, and nothing else would indicate a poor climb -- even with engine and airfoil performance. Tried to climb to FL330 later at 3000 pounds lower and aircraft still only climbed at 200 FPM with no ice protection on. We had an FAA aircraft maintenance inspector on, who also agreed there would be no reason for the poor performance -- other than a weight discrepancy. Requested FL290 and a vector off course due to aircraft performance with ZLA, which was given.

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Original NASA ASRS Text

Title: MD80 CREW HAD ACFT CLB PERFORMANCE THAT INDICATED THE ACFT WAS MUCH HEAVIER THAN THE WT MANIFEST INDICATED.

Narrative: ACFT PERFORMANCE. ACFT CLRED TO CLB FROM FL290 TO FL330 -- NO DELAY IN CLB. SUSPECT THE LOAD AND WT WERE INCORRECT, AS I HAVE NEVER SEEN THIS PERFORMANCE IN 10 YRS ON ACFT, AND NOTHING ELSE WOULD INDICATE A POOR CLB -- EVEN WITH ENG AND AIRFOIL PERFORMANCE. TRIED TO CLB TO FL330 LATER AT 3000 LBS LOWER AND ACFT STILL ONLY CLBED AT 200 FPM WITH NO ICE PROTECTION ON. WE HAD AN FAA ACFT MAINT INSPECTOR ON, WHO ALSO AGREED THERE WOULD BE NO REASON FOR THE POOR PERFORMANCE -- OTHER THAN A WT DISCREPANCY. REQUESTED FL290 AND A VECTOR OFF COURSE DUE TO ACFT PERFORMANCE WITH ZLA, WHICH WAS GIVEN.

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.