B737-700
Flight Crew Air Transport Pilot (ATP)
Workload; Distraction; Confusion
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Ground Event / Encounter Other / Unknown
Flight Crew FLC complied w / Automation / Advisory; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action; General Declared Emergency
Aircraft
Pushback midmorning local; Ground personnel notified us that hand signals required. Clearance to push back obtained from Ramp Control; referencing an aircraft behind us when clear. Pushed part way back; waiting for the aircraft to taxi [when] Ground personnel indicated APU fire with hand signals; pointing to the tail. Captain completed Emergency Checklist items for APU fire. I read and verified the checklist was completed. I called Ground to report APU fire indications; requesting assistance. No cockpit indications noted of an APU fire; other than ground crew reports. No fire warning; smoke or fumes; no indications from the cabin crew. Ground crew then reported no further indications of fire after shutdown of the APU. Captain elected to have the aircraft towed back to the gate for deplaning; since no further reports of fire were noted. I called Operations; asking them to notify Company and Maintenance. Passengers deplaned in an orderly manner. Fire Department trucks had no indications of fire. Maintenance checked the aircraft and allowed passengers to re-board to claim their personal belongings and luggage which was still on the aircraft. Flight was canceled and passengers accommodated. Ground crew reported (after the event) that the fire was noticed near the trim tab on the left horizontal stabilizer; without any indications at the APU exhaust port on the tail. Maintenance assumed control of the aircraft for investigation.
[Report narrative contained no additional information].
A ground crew pushing a B737-700 from the gate reported an APU fire; so the QRH was completed; an emergency declared and the aircraft towed back to the gate where no evidence of a fire was found. No fire warning sounded.