Narrative:

On approach; but prior to landing; the first officer requested gear down and flaps full. I selected the requested configuration requests and the aircraft began to shake. I recycled the brakes and brought the flaps back to position 3. I stowed and rearmed the speed brakes prior to selecting gear down and flaps full. Again the aircraft began to shake pretty violently. A firm but safe landing was accomplished. We taxied to the gate and I contacted maintenance and advised them of what just occurred. I also briefed the receiving crew. Upon investigation by local maintenance; it was discovered that we landed with speed brakes 1 and 3 deployed. They were supposed to be locked down prior to leaving the hangar in denver (they were deferred). I spoke to [maintenance] after learning what happened and was told that the mechanic left the spoilers in maintenance mode. They were not set for flight. As such; they deployed when they were supposed to be locked down.

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Original NASA ASRS Text

Title: A320 Captain reported noticing vibration in flight when flaps were extended that was found to be speed brake panels deployed in flight because they were not locked down in accordance with the MEL.

Narrative: On approach; but prior to landing; the FO requested gear down and flaps full. I selected the requested configuration requests and the aircraft began to shake. I recycled the brakes and brought the flaps back to position 3. I stowed and rearmed the speed brakes prior to selecting gear down and flaps full. Again the aircraft began to shake pretty violently. A firm but safe landing was accomplished. We taxied to the gate and I contacted maintenance and advised them of what just occurred. I also briefed the receiving crew. Upon investigation by local maintenance; it was discovered that we landed with speed brakes 1 and 3 deployed. They were supposed to be locked down prior to leaving the hangar in Denver (they were deferred). I spoke to [maintenance] after learning what happened and was told that the mechanic left the spoilers in Maintenance mode. They were not set for flight. As such; they deployed when they were supposed to be locked down.

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.