Narrative:

On initial climb out from ZZZ; ECAM indicated right #1 (inboard) ground spoiler deployed (up). This was confirmed by approximately 2.5 degrees right bank; rudder trim to the left; and aircraft buffeting. After conferring with dispatch and maintenance control; we returned to ZZZ for maintenance action. This was the aircraft's first flight following extensive maintenance at ZZZ. Subsequent maintenance investigation revealed the ground spoiler valve had been unintentionally left in an incorrect position for flight. Unfortunately; oversights occur. This perhaps should have been caught by a follow-on inspection to make sure maintenance controls are put back in proper position prior to dispatch.

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Original NASA ASRS Text

Title: A320 IS DISPATCHED FOLLOWING EXTENSIVE MAINT AND RIGHT WING SPOILER EXTENDED WHILE IN FLT. DETERMINED GND SPOILER VALVE HAD NOT BEEN RETURNED TO THE FLT POSITION.

Narrative: ON INITIAL CLBOUT FROM ZZZ; ECAM INDICATED R #1 (INBOARD) GND SPOILER DEPLOYED (UP). THIS WAS CONFIRMED BY APPROX 2.5 DEGS R BANK; RUDDER TRIM TO THE L; AND ACFT BUFFETING. AFTER CONFERRING WITH DISPATCH AND MAINT CTL; WE RETURNED TO ZZZ FOR MAINT ACTION. THIS WAS THE ACFT'S FIRST FLT FOLLOWING EXTENSIVE MAINT AT ZZZ. SUBSEQUENT MAINT INVESTIGATION REVEALED THE GND SPOILER VALVE HAD BEEN UNINTENTIONALLY LEFT IN AN INCORRECT POS FOR FLT. UNFORTUNATELY; OVERSIGHTS OCCUR. THIS PERHAPS SHOULD HAVE BEEN CAUGHT BY A FOLLOW-ON INSPECTION TO MAKE SURE MAINT CTLS ARE PUT BACK IN PROPER POS PRIOR TO DISPATCH.

Data retrieved from NASA's ASRS site as of May 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.