For reminder:
The second demo flight is planned to last for 30 minutes. Before the plane took off, air controllers at Halim contacted ATC. They communicated closely: "Hello, approach request release, Mas. RA36801 to the Bogor Area in five minutes." The controller even joked, "RA36801 OK. Direct or through Tangerang?"
At 14:05 (0705 UTC), the second demonstration flight requested start and pushback
At 14:10 pm asking for permission to start engines
at 14:14 the flight cleared for taxi runway 06
at 14:18 ATC issued clearance to the flight that after take-off initially to maintain runway heading until passing 2000 feet, then to make a right turn to intercept radial 200 from HLM VOR and climb to 10,000 feet.
At 14:19 the flight was cleared for take-off
At 14.21 the flight was airborne and instructed to contact Jakarta Approach
14:24
SSJ: Tower 36801 good afternoon, establish Radial 200 degrees VOR 10,000 feet…
ATC: “RA36801 radar contact, maintain 10,000 feet and proceed.
SSJ: Maintain level at 10,000 feet 36801
pilots were flying IFR
14:26
SSJ: Tower, 36801 request descend 6,000 feet
ATC: 36801 say again request
SSJ repeated
ATC: Okay, 6,000 copied
As usual each afternoon, the traffic in the skies over Jakarta was hectic...ATC was personally serving 13 flights simultaneously. According to one tower worker, although five people were listed as being on duty at that hour of the day, N was alone and unassisted.
14:28
SSJ: Tower, 36801 request turn right circle present position
ATC: RA 36801 approve circle to the right 6,000
The request to turn the plane was the last communication from the pilot. Nearly five minutes later (14:33), the plane crashed into the ridge. From the black box recording, according to one Russian investigator, a moment after the request was approved, the pilot shrieked, "O Bozhe, chto eto takoe? (Oh God, what is this?)"
The controller only realized what had happened 24 minutes later. The plane was no longer on the radar screen. He tried to contact the Sukhoi three times, but there was no reply.
14:52 pm, ATC called Soekarno Hatta Airport because the plane is not visible on the radar monitor
much more here:
The ivory tower
and here:
Control Tower Played a Role in Sukhoi Tragedy, finds Tempo Investigation | nasional | Tempo.co
I suppose that report will be released soon