Eighteen people were onboard the Spanish-designed CASA C-212 when it lost contact with air traffic control halfway through its 30-minute flight between North Sumatra and Aceh provinces early Thursday.
Minutes later, the turboprop-powered aircraft sent out a distress signal and then dropped off the radar.
Rescuers have so far been unable to reach the crash site near the mountainous village of Bahorok because of rugged terrain and torrential rains.
Wreckage of the aircraft — spotted during an aerial survey on Thursday and again on Friday — appeared to be largely intact, wings still fused to the body, said Robur Rizallianto, a safety manager with the airline, PT Nusantara Buana Air.
“One of its doors is open,” Rizallianto said, adding that the wreckage lies on a 60-degree slope at an altitude of 5,000 feet (1,524 meters).
There were no signs of the 14 passengers — four of them children — and four crew members. But it provided rescuers with some hope that there may be survivors inside.
However, it is also possible that the door simply opened on impact, said Sunarbowo Sandi, head of the local search and rescue team.
He said thick fog and hilly jungle were hampering rescue efforts, but hoped that land rescuers would be able to reach the scene Friday afternoon.
Authorities were also planning to parachute in Air Force elite troops who could build a helipad there so helicopters could reach the area, he said.
The aircraft, made in Indonesia in 1989, was last inspected on Sept. 22, said Rizallianto. It was in good condition, he said, and a check ahead of takeoff Thursday also came up clean.
Indonesia, a sprawling archipelagic nation of 240 million people, has been plagued by transportation accidents in recent years, from plane and train crashes to ferry sinkings. Many are blamed on overcrowding and poor safety standards.
