Date: 201606
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: Mixed
Light: Daylight
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Electrical Wiring & Connectors
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Second reporter function: Pilot Flying; First Officer
Anomaly: Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Aircraft Equipment Problem Dissipated; Flight Crew Landed As Precaution; Flight Crew Diverted; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: During cruise at an intermediate altitude of FL310; we were deviating around weather along our route. We were about to enter icing conditions so I turned the start switches to continuous and applied engine anti-ice. About two minutes later we noticed an electrical smell that quickly became very strong. We immediately complied with the Smoke; Fire; or Fumes QRC. After establishing flight deck communications; we informed ATC and asked to divert. We were cleared direct and started an immediate descent. I contacted the Cabin Crew to ascertain the conditions in the cabin. One Flight Attendant said she was smelling an acrid odor. I advised them at that time about our situation on the flight deck and said we were diverting. I said I would make a PA soon and brief them when we got caught up on our checklists. I started on the Smoke; Fire; or Fumes QRH while my F/O flew the airplane and dealt with ATC. In complying with the QRH; I also turned off the anti-ice since that's the last thing I did before the electrical smell started. Once checklists were complete; I made a Passenger PA advising them of the situation and we were diverting. I let them know emergency equipment standing by upon our arrival. I let them know we would be landing in 20 minutes and would have more information once on the ground. Below 10;000 ft the odor had dissipated and I asked the F/A's to plan for a normal landing. During the emergency; we advised ATC souls and fuel onboard; contacted Ops to notify them and obtain a gate; contacted Dispatch to advise and amend Release for the destination change. We completed the normal checklists and the diversion checklist. We advised we wanted to turn off the runway; stop; and have ARFF complete an outside visual check and advise. Once stopped; I made a PA to the Passengers as to what was happening and that we would be to the gate soon. ARFF advised the aircraft was good. We asked to be followed to the gate. On the taxi-in; we confirmed Maintenance would meet us at the gate. After shutdown; fire personnel boarded and inspected the flight deck; cargo compartments; and cabin area. Nothing abnormal was identified. Maintenance met us and started checking the aircraft. I contacted Dispatch and Maintenance Control and the necessary logbook entries were made. I established contact with the Chief Pilot on Duty and gave him a run down on what had happened. I briefed my entire Crew on a fantastic job and made sure everyone was okay.


Second narrative: [Report narrative contained no additional information.]


Synopsis: B737-700 flight crew reported an intense electrical fume smell at FL310 shortly after engine ignition and anti-ice were turned on. QRH procedures were complied with; ignition and anti-ice were turned off; and the flight diverted to the nearest suitable airport. The smell dissipated during the descent.