The latest reports from Reuters news agency indicates that a passenger managed to wear their life jacket before the plane had crashed. The fact that one person put on a life jacket would appear to indicate those on board had at least some time before the aircraft hit the water, or after it hit the water and before it sank.
This morning, we recovered a total of four bodies and one of them was wearing a life jacket," Tatang Zaenudin, an official with the search and rescue agency, told Reuters. 162 people had died in this latest crash and the plane was travelling from Surabaya to Singapore. Flight QZ8501 black box flight data and cockpit voice recorder has yet to be found and only then investigators will have some idea on how and what caused the plane to crash.