The Mandala Airlines Boeing 737-200 plunged into a suburb of Medan on Monday, seconds after taking off from the city's airport. A total of 103 of the 117 people on board were killed and 47 people on the ground also perished.
President Susilo Bambang Yudhoyono flew into Medan to attend the burial of North Sumatra Province governor Rizal Nurdin, who was among the victims of Indonesia's worst air disaster in eight years.
Provincial spokesman Edi Sofyan said on Thursday the president would visit the crash site, where investigators from the National Transportation Safety Committee were sifting through the charred carcass of the plane and collecting debris.
Setio Raharjo, a member of the eight-man team, said the black boxes - the flight recorder and cockpit voice recorder, which contain the last communication between the pilot and control tower - had been recovered.
He said the engines would be taken to Jakarta to determine if the crash was caused by engine failure, while the plane's recorders would be sent to the United States, Taiwan or Australia for analysis.
"There are no signs of terrorism"
Mandala Airlines spokesman
Investigators have yet to offer any information about the possible cause of the crash, while Rahajaro said the investigation should take seven to 10 days.
Mandala Airlines spokesman Det Elfisra said foul play was unlikely, saying: "There are no signs of terrorism."
Newspapers expressed concern about airline safety in Indonesia, saying a price war between low-cost operators was a cause for concern at a time when the cost of fuel and spare parts was rising.
"If this absurdity is maintained, surely sacrifices have to be made. In Indonesia, it has become a common matter that passengers, including safety, are being sacrificed," Media Indonesia said.
Monday's crash was the worst in
Indonesia since 1996
The plane split open and burst into flames as it ploughed into a busy street not far from Medan airport.
Residents said the airliner hit a grocery shop before smashing into two-storey shops on the other side of the avenue.
Mandala Airlines was set up in 1969 and is one of several low-cost airlines that fly across the vast Indonesian archipelago. It is partly owned by the military.
Monday's crash was the worst in Indonesia since a Garuda Indonesian Airways A300 Airbus crashed on approach to Medan in September 1996, killing 234 people.
In November last year, an MD-82 plane belonging to budget carrier Lion Air crashed in the central Java city of Solo, killing 26.