A reader asked me about SilkAir 185 that crashed on 19 Dec 1997 and I reproduced below an article from Wikipedia:
SilkAir Flight 185, a Boeing 737-36N, registration 9V-TRF, was a scheduled passenger flight from Jakarta, Indonesia to Singapore, which crashed on 19 December 1997 after abruptly plunging into the Musi River from its 35,000 feet cruise altitude, killing all 97 passengers and 7 crew on board.
Remarkably, the cockpit voice recorder and flight data recorder stopped recording, at different times and for no apparent reason, minutes before the aircraft departed level flight and entered a steep vertical dive.
The crash was investigated by various groups, with different results. The Indonesian NTSC, who were lead investigators, were unable to determine the cause, while the U.S. NTSB concluded that the crash resulted from an intentional act by a pilot, most likely the captain.