Date: 201807
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: VMC
Aircraft: B787-900
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: Turbine Engine
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Second reporter function: First Officer; Pilot Not Flying
Anomaly: Aircraft Equipment Problem Critical
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Aircraft Equipment Problem Dissipated; Flight Crew Landed in Emergency Condition; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Departure Airport
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: I was pilot flying on Flight XXX. It was planned as a reduced thrust flaps 15 takeoff. Winds presented a light crosswind from right. All routine until rotation. As I rotated into the TOGA (Take-off/Go-Around) reference line on the HUD; the aircraft yawed to the left and there was a loud banging from the left side of the aircraft with a marked loss of performance. The Captain and relief pilot called out 'engine failure'. The Captain told ATC that we were experiencing an engine problem and would be tracking on the engine out T-procedure. Another aircraft reported that they had observed 25 foot sheets of flame emanating from our left engine. I continued to follow the command bars and asked for the EO (Engine Out) procedure to be executed on the FMC. At approximately 400 feet AGL I engaged the autopilot. The EO prompt was not available on the FMC; so I engaged HDG SELECT on the MCP (Mode Control Panel) and flew the engine out T procedure with the heading bug; utilizing the VOR radial/DME guidance that had been preset in the box before takeoff. The banging stopped and aircraft performance improved. Flaps were retracted on engine out schedule at 800 feet AGL. The left engine had returned to normal operating parameters. We ran the ENG SURGE L Emergency Checklist as prompted by the EICAS. The checklist directed us to continue the flight as the ENG SURGE message remained blank with all the engine parameters in the normal range. None of us on the crew thought it an appropriate course of action to take the aircraft on a continued 14 hours ETOPS flight. Coordination was made with ATC for delay vectors and a fuel dump; having to avoid some weather off the coast. Captain conference called on SATCOM and Maintenance Control concurred that returning to [the departure airport] was the appropriate course.After adjusting our gross weight to maximum landing weight; a normal and uneventful approach and landing was made and we taxied to the gate.


Second narrative: Compressor Stall on TakeoffLeft engine compressor stall on rotation; approximately three surges with loses and increases of thrust on each surge. First Officer accomplished engine failure on takeoff profile and routing. Left engine recovery to full operation evident by acceleration altitude. Captain accomplished Engine Surge Checklist; coordinated with Dispatch and Maintenance. Captain accomplished Fuel Dump checklist overwater FL230 to maximum landing weight. First Officer [did the] approach and landing.Biggest threat to crew communication and engine failure on takeoff profile was repeated Tower communication. Captain communicated engine failure to the Tower Controller and our necessary engine failure routing that deviates from ZZZZZ2 departure. Tower Controller continued to inquire/insist clearance of ZZZZZ2.


Synopsis: B787 Flight Crew reported that an engine malfunctioned at takeoff.