Lion Air jet 'flew erratically' evening before Indonesia crash
Two passengers say they had concerns about the plane's air conditioning and cabin lighting during a previous flight.
Tuesday 30 October 2018 18:17, UK
The jet that crashed in Indonesia flew erratically during a flight the previous evening and experienced a "technical problem", according to flight tracking website FlightRadar24.
After taking off from Denpasar on the holiday island of Bali on Sunday evening - the day before the crash - the Lion Air Boeing 737 MAX jet reported unusual variations in altitude and airspeed at the beginning of the flight.
This included an 875ft drop over 27 seconds, when it would normally be ascending, before stabilising and flying on to Jakarta.
However, the pilots kept the plane at a maximum altitude of 28,000ft compared with 36,000ft on the same route earlier in the week, according to FlightRadar24 data.
Lion Air CEO Edward Sirait said on Monday a technical problem had occurred on the Denpasar-Jakarta flight but it had been resolved "according to procedure".
Two passengers on board said they had been concerned about problems with the air-conditioning system and cabin lighting before the plane departed almost three hours late.
One of them, TV presenter Conchita Caroline, said: "I was angry because as a passenger who had paid her ticket, we have every right to question the aircraft's safety."
She added there was a "weird" engine noise on take-off that continued during the flight.
It is not known whether the cabin problems were related to the technical trouble mentioned by the airline's CEO.
The Denpasar-Jakarta flight landed at 10.55pm local time on Sunday, giving engineers six-and-a-half hours to carry out checks before it was dispatched for the fatal Jakarta-Pangkal Pinang flight at 6.20am on Monday.
The plane plunged into the sea minutes after taking off from Jakarta and all 189 people on board are believed to have died.
FlightRadar24 also reported unusual air speeds and altitudes in the few minutes that Flight JT610 was in the air on Monday.
Photographs apparently of technical and maintenance logs following the Sunday flight have been circulating online but they have not been verified as accurate by the airline or investigators.
Mr Sirait would not give details about the maintenance procedures taken.
On Tuesday he said the airline had provided the relevant aircraft flight and maintenance logs to Indonesia's National Transportation Safety Committee (NTSC).
Committee chairman Soerjanto Tjahjono said there was a similarity between the maintenance log circulating online and the one received from Lion Air but he had not checked the exact details.
Safety experts say the crash investigation is at a very preliminary stage and it is too early to speculate about what could have caused the jet to crash.
The data from FlightRadar24 shows the first sign that something was amiss on Monday's fated flight came about two minutes after take-off when the plane had reached 2,000ft.
At that point, it descended more than 500ft and veered to the left before climbing again to 5,000ft, where it stayed during most of the rest of the flight.
It began gaining speed in the final moments and reached 345 knots (397mph) before data was lost when it was at 3,650ft.
Two fishermen who saw the crash from their boat out at sea said they saw the plane sway slightly but made no noise as it fell, almost horizontal with its nose slightly down.
There was the sound of an explosion as it plunged nose-first into the sea followed by a column of smoke.