Date: 201203
Local time of day: 0001-0600
Location: ATL.Airport, GA
Aircraft: Regional Jet 200 ER/LR (CRJ200)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Climb
Airspace: Class B ATL
ATC / advisory: Tower ATL
Second aircraft: Regional Jet 200 ER/LR (CRJ200)
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Situational Awareness; Communication Breakdown
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
Result: Air Traffic Control Issued New Clearance
Contributing factors: Procedure; Human Factors
Primary problem: Procedure

Narrative: While working Local 3; I instructed Air Carrier X to line up and wait on Runway 27R than issued take-off clearance to an SLAWW RNAV. At the same time; Local 2 issued a take-off clearance to Air Carrier Y off Runway 26L on a heading of 280 degrees both controllers observed the aircraft's close proximity off the departure end; Local 2 issued a heading of 290 to Air Carrier Y at the same time Local 3 issued traffic to Air Carrier X and received a response that the pilot of Air Carrier X had the 26L departure in sight and would maintain visual separation before transferring radio communication. I understand the LOA for noise abatement and its procedures completely; but for all practicable purposes these procedures; in reference to the; so called midnight headings are executed differently by different supervisors according to the traffic volume we have. These procedures have also been changed numerous times over the past months for one reason or another leaving the controllers; that I have spoken with; confused on what heading or action we are taking today. Controllers; as well as; some Management Personnel have made their concerns known that the current procedures do not allow for a heading off the north runway that would make an incident; such as this; most likely never occur. Currently these procedures do not allow for minimum separation of 15 degrees if a situation such as this happens. My recommendations to fix this problem would be that the Supervisor shall state to both controllers that we are now using headings; and no longer using the RNAV; and to coordinate with ATL departure; both controllers putting it on the recorded line that headings are in effect to avoid any confusion. In the event; a Supervisor is not present at the time the Local 2 (North) Local 3 (South) will coordinate via the recorded line before changing to a heading; and also advise ATL departure before implementing this procedure. I also recommend that a heading off the north runway; regardless of noise abatement; should always be at least 15 degrees north of the south runway's magnetic heading of 273 degrees.




Synopsis: ATL Controller voiced concern regarding the confusion that exists when transitioning from normal operations to mid shift procedures to accommodate noise concerns; the reporter noted differences between supervisors and lack of clarity during coordination are contributing factors.