Narrative:

While proceeding direct to hanah fix (base leg) at assigned altitude of 5500ft GPWS terrain warning activated with red warning light. Immediately applied escape procedure and warning was over within seconds. I leveled the aircraft at 6000ft and my first officer advised ATC. The controller responded that this was an airbus issue and that the actual minimum vectoring altitude was 5300ft (200ft below our altitude). We were then cleared to 2500ft and proceeded to an uneventful landing on 28L. No engine exceedances were noted.apparently this momentary GPWS terrain warning can occur on airbus aircraft when at 5500ft in one small area of arrival patterns for runway 28L.I have made numerous arrivals at pdx and never had this occur. Not sure what the answer is to prevent this from happening unless delaying descent below 6000ft in that spot would be acceptable. A workable solution is needed since having to perform escape maneuver at a late hour is quite stressful.

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Original NASA ASRS Text

Title: A320 Series Captain reported receiving an erroneous GPWS terrain warning on approach to PDX Runway 28L. Controller reportedly stated that this was a known Airbus issue.

Narrative: While proceeding direct to HANAH fix (base leg) at assigned altitude of 5500ft GPWS Terrain Warning activated with red warning light. Immediately applied escape procedure and warning was over within seconds. I leveled the aircraft at 6000ft and my First Officer advised ATC. The controller responded that this was an Airbus issue and that the actual minimum vectoring altitude was 5300ft (200ft below our altitude). We were then cleared to 2500ft and proceeded to an uneventful landing on 28L. No engine exceedances were noted.Apparently this momentary GPWS Terrain Warning can occur on Airbus Aircraft when at 5500ft in one small area of arrival patterns for runway 28L.I have made numerous arrivals at PDX and never had this occur. Not sure what the answer is to prevent this from happening unless delaying descent below 6000ft in that spot would be acceptable. A workable solution is needed since having to perform escape maneuver at a late hour is quite stressful.

Data retrieved from NASA's ASRS site 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.