Summary
On March 29, 2019, a Jetstar Airways Pty Ltd. Boeing 787-8, registered VHVKJ, operating as scheduled flight JQ15 from Cairns Airport to Kansai International Airport, experienced a serious incident involving a temporary loss of thrust in both engines during descent. The aircraft landed safely at 19:19 JST with no injuries to persons or damage to the aircraft.
Flight History
The flight departed Cairns Airport at 13:11 AEDT with 313 persons on board (pilot in command, 11 crew, and 301 passengers). During descent at approximately 18:53 JST, at an altitude of about 4,900 m, the right engine instrument display became unstable, accompanied by "ENG THRUST R" and "ENG CONTROL R" EICAS messages. At 18:54, an "ENG FUEL SPLIT VALVE R" message appeared. At 18:57, at about 3,600 m, an "ENG FAIL L" message appeared and disappeared shortly; continuous parameter logging recorded the left engine running below idle for eight seconds. At 18:58, an "ENG FAIL R" message appeared and disappeared; the right engine ran below idle for 81 seconds. The pilot disengaged the right autothrottle and set the thrust lever to idle per the checklist. The right engine parameters remained unstable until landing. At 19:08, an "ENG CONTROL L" message appeared. The aircraft landed at 19:19.
Aircraft and Engine Information
The aircraft was a Boeing 787-8 (serial number 36236, manufactured July 1, 2015) with a total flight time of 18,156 hours and 48 minutes. The left engine (General Electric GEnx-1B, serial number 958172) had 1,602 hours and 40 minutes total time; the right engine (serial number 956289) had 18,556 hours and 16 minutes. Weight and balance were within allowable ranges.
Meteorological Conditions
Weather at Kansai International Airport around the incident time was good: wind 240° at 7 kt at 18:30, CAVOK, temperature 13°C. No icing or volcanic ash was encountered.
Technical Details
Both engines experienced oscillations in core speed (N2) that became noticeable during descent, leading to "ENG FAIL" messages and automatic ignition activation. The oscillations were present during the first flight after biocide treatment on March 27, but were initially small. Engine fuel system components were removed and sent to a laboratory in the United States for investigation.
Findings
The Japan Transport Safety Board classified this as a serious incident under Article 166-4 (xvii) of the Ordinance for Enforcement of the Civil Aeronautics Act of Japan, equivalent to "Continued loss of thrust of engines in flight." No probable cause is stated in the source document.