B757-200
Air Traffic Control Fully Certified
Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors; Procedure
I was providing training on an uninvolved position at the time of the incident. I witnessed Arrival Sector X turn a B767 from downwind to base about 10 miles too early and made no attempt to fix the situation he created. He was worried about getting too close to [Runway] 9R arrivals that were descending from above but didn't think about staying away from the low side Arrival Sector Y Controller's airplane (a B757). We were just briefed regarding the ability to use lower altitudes with coordination with other positions. I heard Arrival Sector Y say to him something to the effect of 'what are you doing; I've got an airplane there'. The Arrival Sector X Controller just sat there and watched it all happen. I asked the Arrival Sector Y Controller if he asked to use 4;000 FT on his side; He replied 'no; he couldn't have cared less that he had a deal with my airplane'. My estimate between the B767 and B757 was 500 vertical; 2.25 laterally with no divergence. The Arrival Sector X Controller is one of the weaker controllers here; and even though I work with him less than 5 hours a month; it seems I always see things like this go unchecked; violating the SOP; common sense; and most of all SAFETY. I don't know why he does these things. I would suggest skill enhancement training for the Arrival Sector X Controller throughout the operation. I am concerned when he is here.
TRACON Controller voiced concern regarding the actions of a fellow Controller that resulted in a loss of separation event.