Saab 340 Undifferentiated
Air Traffic Control Fully Certified
Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors; Procedure
I was working South RADAR. Air Carrier X was cleared for takeoff on the SID on Runway 33 which requires leaving 600; turn left heading 300; climb to 4;000. Air Carrier Y was cleared for takeoff shortly thereafter on the same departure. Air Carrier Y appeared on RADAR about 2.5 miles in trail of Air Carrier X about 1;500 FT below. I noticed this situation at this time and immediately slid over to the North RADAR Controller to inform them of the overtake in climb as Air Carrier Y was climbing faster than the previous aircraft. At this time separation was lost. Air Carrier Y was then switched to Departure and the North RADAR Controller immediately turned the second aircraft (Air Carrier Y) thirty degrees to the left to re-acquire separation and issued traffic. The aircraft were both IMC at the time of the incident. This is the third overtake situation I have noticed in the past week with Tower to Departure. The first two I was able to fix without a loss of separation. I believe the controllers working in the Tower need training on RADAR separation.
I was working North RADAR when Air Carrier X; departed north on the SID; climbing to 4;000 on heading 300. I RADAR identified the aircraft; climbed to filed altitude and sent aircraft on course (about a 280-290 heading). I then started to work other aircraft in the airspace. Shortly thereafter; South RADAR came to my position to ask me if I was talking to Air Carrier Y. Air Carrier Y was on the same departure SID as his company and had not yet checked onto frequency. Air Carrier Y appeared to be less than 3 miles in trail of Air Carrier X and less than 1;000 FT vertically. Moments later; Air Carrier Y checks onto frequency climbing to 4;000. I immediately turn the aircraft left to a heading of 250 (a turn north was not an option due to IFR traffic level at 4;000) and issued traffic. Air Carrier Y stated they had company insight and they were instructed to maintain visual separation. I believe that no form of separation was ensured by Tower prior to Air Carrier Y being shipped to Departure. My first transmission to Air Carrier Y was a turn to ensure separation. These overtake scenarios on departure are becoming a common; daily occurrence here. I believe that some of the Tower controllers here do not ensure separation with departing aircraft and once airborne; merely ship the aircraft prior to resolving all conflicts. Coordination could have been completed with Departure for separation to be maintained with these aircraft. The overtake on departing traffic was either ignored or not even recognized by the local controller. Conflicts are not resolved prior to aircraft being shipped to Approach. I would suggest training on required separation; scan training; aircraft performance training and required monitoring done in the approach environment.
TRACON Controller described a conflict event resulting from a lack of awareness on the part of the Tower; the Tower failing to provide adequate separation between two successive IFR departures.