INDONESIA's National Transportation Safety Committee (NTSC) said the crashed 737 Max aircraft off Jakarta had faulty airspeed readings during its last four flights, reports Bloomberg.
The agency, assigned to determine the cause of the Lion Air crash that killed 189 people, said it made the discovery from records of previous flights retrieved from the wreckage.
With the data recorder - but not The voice recorders - is in the hands of investigators. The NTSC has 69 hours of flying data during its last 19 trips.
Because Flight JT610 lasted only a few minutes, the voice recorder is also likely to include at least some audio from the previous night's trip from Denpasar, Bali to Jakarta.
The aircraft experienced problems on the flight from Bali with sensors used to calculate altitude and speed. Maintenance workers overnight checked the instruments and the plane was cleared to fly, according to Lion Air.
Even with modern GPS tracking, planes need to calculate their precise speed through the air. To determine airspeed, which can vary substantially compared to the speed over the ground due to winds.
By comparing that pressure against the ambient air pressure - which is obtained by what are known as static ports - aircraft can determine airspeed. If either of the pressure sensors were blocked, it can cause erroneous readings.
Underwater currents in the Java Sea off Jakarta and a muddy seabed have complicated a weeklong hunt that's involved dozens of ships and hundreds of specialist personnel.
Inspection of debris indicated the aircraft didn't explode mid-air. 'The aircraft broke apart under the impact of hitting the water at high speed,' said NTSC chief Soerjanto Tjahjono. 'The engines were still running at high RPM.'
The agency, assigned to determine the cause of the Lion Air crash that killed 189 people, said it made the discovery from records of previous flights retrieved from the wreckage.
With the data recorder - but not The voice recorders - is in the hands of investigators. The NTSC has 69 hours of flying data during its last 19 trips.
Because Flight JT610 lasted only a few minutes, the voice recorder is also likely to include at least some audio from the previous night's trip from Denpasar, Bali to Jakarta.
The aircraft experienced problems on the flight from Bali with sensors used to calculate altitude and speed. Maintenance workers overnight checked the instruments and the plane was cleared to fly, according to Lion Air.
Even with modern GPS tracking, planes need to calculate their precise speed through the air. To determine airspeed, which can vary substantially compared to the speed over the ground due to winds.
By comparing that pressure against the ambient air pressure - which is obtained by what are known as static ports - aircraft can determine airspeed. If either of the pressure sensors were blocked, it can cause erroneous readings.
Underwater currents in the Java Sea off Jakarta and a muddy seabed have complicated a weeklong hunt that's involved dozens of ships and hundreds of specialist personnel.
Inspection of debris indicated the aircraft didn't explode mid-air. 'The aircraft broke apart under the impact of hitting the water at high speed,' said NTSC chief Soerjanto Tjahjono. 'The engines were still running at high RPM.'