B747 Undifferentiated or Other Model
Flight Crew Last 90 Days 188; Flight Crew Total 11245; Flight Crew Type 8241
Workload
Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Returned To Departure Airport
Aircraft
Passing 10;000 feet; a flight attendant called and reported an electrical burning smell; but no smoke; throughout the main and upper deck cabins.  The crew discussed this smell and the Captain said that he could smell it also.  A minute after discussing the smell; the Right Util Bus EICAS message displayed followed shortly with the Left Util Bus EICAS message.  Accomplished the Smoke; Fire; or Fumes QRH and the Captain declared a mayday with [ATC] and requested vectors for a return to ZZZZ.  Crew discussed and decided not to dump fuel due to the nature of the emergency and the proximity of ZZZZ.  A message was sent to Dispatch declaring our Mayday; the nature of our emergency; our intention to divert to ZZZZ and land overweight.  Landing performance data was requested from dispatch and checked by the crew.  Radio called to ZZZZ operations to notify them of our emergency and return to ZZZZ.  Notified approach [that] we wanted the fire equipment waiting for us after landing.  The electrical smell had dissipated.  Uneventful overweight landing on RWY XXR with a turnoff near the end.  Cleared the runway and evaluated the brake temperatures and any other related problems and found everything normal.  Declared ops normal to ground control was given taxi clearance to stand.
I was PF. The Captain told me to turn the autopilot on and that he would work the checklists with the relief pilots. We elected to get the aircraft on the ground ASAP. I continued as PF while the rest of the crew called Dispatch and Station; coordinated with the Lead Flight Attendant; and worked checklists. We had an uneventful overweight landing at 745;000 lbs.
B747 crew described a return to departure airport for an electrical burning smell a Flight Attendant noticed.