Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 157; Flight Crew Total 2966; Flight Crew Type 706
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Returned To Gate; General Maintenance Action; General Flight Cancelled / Delayed
Aircraft; Procedure
Two previous write ups indicated FAs could feel something shaking/moving under the floor of the aft galley. I briefed the purser and asked that all FAs be made aware of this and be looking for it. Additionally I made a non rev pilot aware of the possible problem. As we pushed I got a call from the back and both the FA and the non rev CA could feel the shaking. We pulled back to the gate and called maintenance. After about an hour of trouble shooting it was discovered to be the equipment cooling fans. When the mechanic went directly to the fans; one of them was shaking and was much hotter than the other. Maintenance Control was involved and wanted the single fan made inoperative and then continue per MEL deferral. I watched closely as the deferral procedure was being efforted. It was discovered that when the problem fan was deactivated; the other fan would not operate. With two fans inoperative there was evidently no MEL data that allowed dispatch. The following is paraphrased only slightly: Maintenance Control then said 'ok; we know what the problem is now; plug them both back in and we'll get this flight out and fix it later.' Hearing that I knew I was refusing the airplane. I got the passengers off and called the Duty Manager. I also watched closely as the mechanic refused Maintenance Control. I told the Duty Manager what was going on and explained I was very angry with Maintenance Control. The Duty Manager understood and got a hold of local maintenance supervisor. That supervisor and I made a plan (deliberately apart from Maintenance Control about how to continue using the safest most conservative approach: fix the airplane. The parts were on hand so the repair started. Two line mechanics started the repair and got it done in about an hour and a half. We [pilots] timed out however; and the flight had to be delayed a day.
B767 Captain reports accepting an aircraft with previous write ups for shaking/vibration under the aft galley floor. The problem reappears as the aircraft is pushed back and Maintenance is called. The problem is traced to an equipment cooling fan; which Maintenance Control wants the crew to take as is and the crew declines.