B737-700
Air Traffic Control Fully Certified
Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict
Air Traffic Control Issued New Clearance
Human Factors
A B737-700 is typically given a clearance to cross 50 South DPK level 250 by ZDC CYN Sector. A MD-88 given cross 65 West HTO level 270; started descending out of 310. Heard another Controller mention about 2 aircraft at FL450; ranged out to look as it was likely that one or both would transit Sector 56. Conflict Alert began to flash between the B737; (still level at 290) and the MD-88 and I asked the B737 if he had a restriction; he/she did not respond. Shouted on 99 line to 'DESCEND B737 PLEASE!' Turned the MD-88 to 010 heading with expedite turn; first asked to stop at FL300; not possible so I instructed the MD-88 to just stop descent. ZDC; for whatever reason; kept communications with the B737; preventing me from doing anything with the aircraft. The MD-88 leveled at 296 and missed the B737 by several miles at least. Recommendation; treat Saturday night like any other night of the week and manage traffic accordingly.
ZNY Controller described a loss of separation event when one of the aircraft involved did not receive a frequency change in time to be effective.