B737-800
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 215; Flight Crew Type 215
Distraction; Situational Awareness; Training / Qualification; Communication Breakdown
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Flight Crew Landed in Emergency Condition; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Returned To Departure Airport; General Declared Emergency; General Maintenance Action; General Release Refused / Aircraft Not Accepted
Aircraft
Our takeoff was normal. Passing through about 2;000 FT MSL; the flight attendants called the cockpit and stated that they smelled a strong odor of fumes in the cabin. We asked them for more information and after discussion; we determined that the odors were not normal (smelling like burnt rubber or an electrical smell). The passengers in the front cabin; mid-cabin; and aft-cabin also smelled the fume-like odors. We then put on our oxygen masks and requested an immediate return from Departure Control. We declared an emergency and ran the 'Smoke/Fire/Fumes on the Aircraft' Checklist.Communication proved difficult with the new -800 oxygen masks in flight as the loud sound of breathing made it difficult to hear. We landed and had the fire trucks follow us to the gate. The burnt smell continued (on and off) during the return to the airport and also on the taxi-in to the gate. The Fire Department then made their checks on the aircraft at the gate. We made three logbook entries; (1) the burnt; electrical odors with the emergency return; (2) a flaps 40 over speed of 3 knots (165 KIAS); and (3) an overweight landing (landing weight about 148;200 pounds). We then switched aircraft and continued on uneventfully. We need to practice with the new -800 oxygen masks during PT's and PC's.
The reporter stated that the WIFI system overheated and was producing a burning electrical odor. There was no smoke with the overheat.
[Narrative 2 contains no additional information]
Shortly after takeoff; the B737-800 flight attendants notified the pilots of a burnt electrical odor so an emergency was declared and the flight returned to the departure airport. The pilots reported difficultly communicating using the new style O2 masks and the odor's source was the WIFI system.