The descent calls to the Russian plane were late. They were SO late that DHL had already called their own RA that they were maneuvering for.
I suspect that part of the delay was that the Russians were being told to climb by their TCAS and decend by ATC. If that was the case and stuck with that choice, they chose badly.
ALWAYS follow the RA. The controller is NOT in the loop of the negotiations between the two aircraft carrying out the avoidance maneuver and doesn't know who has been told to climb and who has been told to descend by the respective TCAS systems. DO MAKE A TURN if given by the controllers, but DO NOT allow the controller to overide the TCAS instructions as to climbing, decending, increase climb, maintain climb, etc...
A suprising number of people don't know that...
(wildass speculation begins)Furthermore, that 154 looks like a 727, and probably can come down like a bag of hammers just like a 727 (IOW a much greater descent rate is possible from the 154) and so even though DHL might have started down first, the 154 could have caught it...(Wildass speculation stopped)
CHeers
Wino