Talking with the press, Minister of Transport Budi Karya Sumadi said authorities will conduct a special audit of the crews' qualifications and staff communication. This is a preventative measure and the accident is a very expensive lesson, he said.
Civil aviation authorities in the US and Europe were also being consulted for their help in the probe, he added.
The ministry had previously removed several Lion Air executives and technicians, saying they were needed to help authorities in the investigation.
The budget carrier has been a regular target of complaints about poor service, unreliable scheduling and safety issues, including a fatal 2004 crash.
The Lion Air investigation comes after the Indonesian government ordered an inspection of all Boeing 737 Max 8 planes in the country.
A week after the disaster, there is still no answer as to what caused the accident. Meanwhile, authorities have extended their search as they collect more body parts and shattered debris from the spot where the plane crashed.
Scores of body bags filled with remains have been collected and sent for DNA testing, but so far just 14 people have been identified.
Search and rescue agency head Muhammad Syaugi tearfully apologised as relatives' clamour for answers grew louder, with accusations that the pace of recovery is lagging.
Divers have pulled the plane's flight data recorder from the water, but are still hunting for the cockpit voice recorder, a key device that could provide clues to what caused the almost brand-new plane to plunge into the sea.
The jet, a Boeing 737 MAX 8, was en route from Jakarta to Pangkakpinang in Bangka Belitung province off Sumatra island. It lost contact with air traffic control just 12 minutes after takeoff.
The incident is reported to be the first major accident involving a Boeing 737 Max – an updated version of the 737.
The Lion Air crash was the worst airline disaster in Indonesia since 1997, when 234 people died after a Garuda flight crashed near Medan.–VNA