B737-700
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 278
Aircraft Equipment Problem Critical
General Maintenance Action; General Release Refused / Aircraft Not Accepted
Aircraft
During a thru flight stop; a Flight Attendant told me she heard a loud noise in the tail section that sounded like a thumping that was continuous. The aircraft had had a lightning strike a few days prior to our flight. Maintenance had also done some flight control repairs prior to our flight. I decided to call Dispatch and through them Maintenance Control. I had the First Officer move the rudder and I listened to see if I could hear the noise; which I did. Contract Maintenance was called and the plane was taken out of service.
After landing and parking aircraft during thru flight it was brought to the attention of the flight crew by a Flight Attendant of noise coming from rear of aircraft. Upon further inspection by Crew and Contract Maintenance; noise and vibration was a result of the rudder control as it was moved on the ground.
During an enroute stop a Flight Attendant reported a continuous 'thumping' noise in the aft body. The flight crew determined it to be related to rudder operation and; having occurred subsequent to recent flight control maintenance at the previous stop; it was deemed unfit for service.