Date: 202110
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Light: Daylight
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
Airspace: Class B ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: Electrical Distribution
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Time Pressure; Troubleshooting
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Clearance; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Detector: Automation Aircraft Other Automation; Person Flight Attendant; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Returned To Departure Airport; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: All operations normal; flaps 5 takeoff; departing Runway XX on the ZZZZZ1 out of ZZZ. Captain; Pilot Flying; First Officer; Pilot Monitoring. Upon flap retraction from flaps 1 to flaps up; we received a Master Caution light. Associated with the Master Caution light was the following; Overhead; HYD; Fuel; Electric and anti-ice lights. At just about the same time the First Officer lost all cockpit display system instrumentation; primary flight display and primary and navigation display; as well as his flight management computer. The flaps were stuck at position one even though the flap handle was in the up position and seated. Multiple failures in rapid succession. Keep in mind; we are still in the takeoff regime of our flight; while trying to communicate with the Tower Controller handing us off to the Departure Control; while communicating between ourselves as to what we saw; and the appropriate actions necessary. I told the First Officer to [request priority handling] and a return to the airfield. We told the Departure Controller souls on board and amount of fuel onboard while turning up wind; All the time accomplishing the cover of the QRH; over and over. I flew the aircraft and talked with ATC while the First Officer kept an open line of communication with the cabin crew; while preparing the aircraft for a flaps 1 overweight landing. On a right; downwind flaps1 to Runway XX; prior to turning base; the cabin crew advised the right side of the cabin was dark and we smelled fumes. I told the Tower we needed to land immediately and made the turn to join final Runway XX. I told the First Officer to advise the cabin crew and passengers we would be stopping on the runway; to remain seated and standby for further instructions. It was a smooth landing. Airport Rescue Firefighters (ARFF) met the aircraft and did an inspection and found no indication of smoke or fire. I made the decision not to evacuate the aircraft at that time. I had the fire department follow us to the gate and let us know if they saw any smoke or fire; that would prompt an immediate evacuation of the aircraft. Once we arrived at gate; fire department personnel boarded the aircraft as passengers were deplaning. We were in the air a total of 18 minutes; either in the takeoff phase or landing phase of flight. No injuries.


Second narrative: All operations normal departing on XXL on the ZZZZZ1 out of ZZZ.  Upon flap retraction from 1 to UP; we received a Master Caution light with the OVERHEAD; HYD; FUEL; ELECTRIC and ANTI-ICE annunciators lit.  FO (First Officer) lost all information on the two right side displays as well as the right side FMC.  Flaps stayed at 1 with the handle positioned to UP.  Captain continued to hand fly the aircraft and kept speed at 205 knots with speed window remaining open. ATC queried about loss of MODE C and requested altitude passing.  Flight Attendant called and mentioned loss of right side and fumes. FO incorrectly assumed loss of right side engine initially from FA assessment but later confirmed it was loss of right side cabin lighting. Captain immediately requested a return to ZZZ and FO coordinated a right turn for visual to Runway XY. Two good engines and generators.  While Captain hand flew the aircraft; the FO set up Captain side navigation radios; Mode Control Panel and loaded an approach into the FMC.  Visual to the longest runway; XY; was chosen for a flaps 1 landing. FO coordinated with F/As for the emergency return and informed them we would be full stopping on the runway and emergency crash response vehicles will be looking over the aircraft; and we will not be evacuating the aircraft immediately. There was time to run equipment cooling QRH and placed in alternate.  On downwind; Pilots noticed the slight acrid smell of an electrical fire which got stronger throughout base and final. Touchdown was soft in the first 1;000 feet and landing roll went just past the 2;000-foot remaining marker.  Fire response looked aircraft over and determined no visible smoke or fire.  Captain elected to taxi to gate and deplane using a jetway. FO turned off recirc fans; IFE; Galley switches.  APU was not started and ground power but no air was used at gate. After shutdown pilots noticed the strong acrid smell in the cabin.  Fire response inspected aircraft and found no evidence of fire or smoke.


Synopsis: Air carrier flight crew reported an electrical system malfunction accompanied by cabin fumes. Air crew completed the QRH procedure and executed a safe return to departure airport.