"We felt like in a roller coaster".
Search teams have taken up the grim task of separating human remains from plane debris and recovered personal effects, sending the body parts - including from an infant - to hospital for DNA testing.
"The erratic flight path makes us suspect a problem with the pitot-static system", he said.
A video showed the device being brought on board one of the rescue ships in the sea off Jakarta on Thursday, four days after the Boeing 737 MAX 8 jet disappeared off radar during a routine short-haul flight.
At a news conference, Muhammad Syaugi of Indonesia's National Search and Rescue Agency said the identification process was proceeding as quickly as possible, but said it was unlikely the remains of all passengers would be found.
First Victim Identified Relatives are desperate to find traces of their loved ones, but so far only body parts and debris have been found.
Lion's safety record - including a fatal 2004 crash and a collision between two Lion Air planes at Jakarta's Soekarno-Hatta airport - will also be looked at, he added. All people on board are presumed to be dead.
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The former army captain has promised heightened power to the military and to the police, including the ability to kill suspects. Reducing the budget deficit through pension and tax reform tops the list of necessary reforms, according to Mercedes' Schiemer.
The recovery of the black box - which monitor plane's electronics and mechanical systems as well as record the words of the pilots - is the first step toward unraveling the mystery behind the nearly new aircraft's dive into the shallow waters of the sea.
Data from that flight suggested the plane may have flown erratically and a technical log circulating on social media pointed to different speed and altitude readings on the captain and first officer's instruments.
Lion Air chief executive Edward Sirait said on Tuesday that the plane had had technical problems, but had been repaired before being allowed to fly again. The engines were a product of a joint venture between US-based General Electric and France's Safran Aircraft Engines.
The accident has also resurrected concerns about Indonesia's patchy air safety record which led to a now-lifted ban on its planes entering USA and European airspace.
Divers equipped with "pinger" locators have been searching for the piece of equipment, which could hold the key to finding out why the plane, which had been delivered in August, went down.
Indonesian aviation authorities ordered the inspection of 12 other Boeing 737 MAX 8 aircrafts belonging to commercial airlines in the country. The US lifted a decadelong ban in 2016. Earlier this year it confirmed a deal to buy 50 new Boeing narrow-body aircraft worth an estimated $6.2 billion US.
Indonesia's transport minister says the technical director of Lion Air and staff who approved the flight of the jet that crashed have been removed from duty at the ministry's order. It has been expanding aggressively in Southeast Asia, a fast- growing region of more than 600 million people.