Narrative:

After departing about half way to our destination; received ACARS message from dispatcher to return to departure airport for company convenience; due to maintenance issue (vibration in floor between row 7 and row 12). ACARS message stated if aircraft landed at our destination it would be grounded.this aircraft started the day with a transcon to where I picked it up. The inbound crew stated there was an entry in the aircraft log for a vibration in the floor over the wing. Maintenance inspected the aircraft and signed the aircraft log with no discrepancy found. We departed. During the climb the first flight attendant called and stated that the vibration in the floor was still there. I sent an ACARS message to maintenance that the problem was still there. Upon landing maintenance again inspected the aircraft and put speed tape on the wing body fairing seal thinking that was the problem and signed the aircraft log. I told them in both locations I did not think it was the seals; but a gear door problem; they disagreed. We departed and again the first flight attendant called and said the vibration was still there. I sent an ACARS message and shortly we were advised to return. After landing in maintenance started to work on the aircraft. Before I left the aircraft for the new aircraft to continue on to our destination the maintenance lead came up to me and apologized to for not finding the problem the first time. The vibration was coming from the left main gear door; it was moving about two inches due to a problem with a hinge.

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Original NASA ASRS Text

Title: A319 Captain experienced vibration in the cabin floor during cruise on two separate legs. Maintenance had assumed that the problem was discovered and corrected each time. Flight was instructed to return to base; where the aircraft was taken out of service.

Narrative: After departing about half way to our destination; received ACARS message from Dispatcher to return to departure airport for company convenience; due to maintenance issue (vibration in floor between row 7 and row 12). ACARS message stated if aircraft landed at our destination it would be grounded.This aircraft started the day with a transcon to where I picked it up. The inbound crew stated there was an entry in the aircraft log for a vibration in the floor over the wing. Maintenance inspected the aircraft and signed the aircraft log with no discrepancy found. We departed. During the climb the first Flight Attendant called and stated that the vibration in the floor was still there. I sent an ACARS message to Maintenance that the problem was still there. Upon landing Maintenance again inspected the aircraft and put speed tape on the wing body fairing seal thinking that was the problem and signed the aircraft log. I told them in both locations I did not think it was the seals; but a gear door problem; they disagreed. We departed and again the first Flight Attendant called and said the vibration was still there. I sent an ACARS message and shortly we were advised to return. After landing in Maintenance started to work on the aircraft. Before I left the aircraft for the new aircraft to continue on to our destination the Maintenance Lead came up to me and apologized to for not finding the problem the first time. The vibration was coming from the left main gear door; it was moving about two inches due to a problem with a hinge.

Data retrieved from NASA's ASRS site as of April 2012 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.