Flight Crew Air Transport Pilot (ATP)
Troubleshooting; Confusion; Distraction
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Departure Airport; General Maintenance Action
Human Factors; Procedure
Shortly after landing gear retraction we heard a loud banging noise coming from behind the cockpit and L1 (Lavatory 1) door area. The noise was heard by the L1 flight attendant and could be heard in first class; it became louder and faster as we accelerated. We decided to return for a precautionary landing. We told ATC and they gave us vectors to give us time to complete the checklists. We landed under max gross landing weight. Upon arrival at the gate the ramp crew found the patch cord and wireless box still plugged into the aircraft.
[Report narrative contained no additional information.]
MD-82 flight crew reported a loud banging noise due to an open communication panel shortly after gear retraction.