Date: 201702
Local time of day: 1801-2400
Location: MSP.Tower, MN
Aircraft: EMB ERJ 170/175 ER/LR
Operator: Air Carrier
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Climb
Airspace: Class B MSP
ATC / advisory: Tower MSP
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Distraction; Human-Machine Interface; Situational Awareness
Anomaly: ATC Issue All Types; Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Detector: Person Air Traffic Control
When detected: In-flight
Contributing factors: Airspace Structure; Procedure; Human Factors
Primary problem: Procedure

Narrative: I departed an aircraft off of Runway 30R; while another aircraft was in the Arrival Departure Window (ADW) for Runway 35 during converging runway operations. This happened during a very low period of traffic. While I was working Local Control North (LCN) I had no aircraft transitioning through the Class B; no aircraft arriving to my runway; (30R). We have been given either conflicting or no guidance on how to resolve the situation if it happens. The only thing that I do know is that I have had an error if I did this. I would like to point out that I recognized the error when the landing aircraft on Runway 35 was in the first 3rd of the ADW and my aircraft departing was within the first 1000 feet of departure roll. I am fully capable and prepared to separate the aircraft had the aircraft on approach to Runway 35 executed a balked landing. From a safety perspective; I felt it was better to let the aircraft depart Runway 30R rather than cancel the take-off clearance. We have had many procedural changes regarding converging runway operations. First we were told that it was identified as a safety risk in the National Airspace System (NAS) so now we can no longer depart aircraft while aircraft landing Runway 35 are in the ADW. At the time of the incident there was no arrival demand for being in the converging runway configuration. Also the only aircraft on approach to the airport was on the converging runway. When LCN is split off during low periods of traffic it is very difficult to identify when one lone aircraft enters the airspace and is landing Runway 35. Also; it is very easy to forget about that aircraft; even if you notice the aircraft 10 or miles from the airport. This has happened to me and several of my coworkers many times. If this is such a safety risk; then why even land on the converging runway when there is no demand? My recommendation would be to only use the converging runway; (35); when the arrival rate is high enough to warrant the need for an additional arrival runway. In addition; that LCN not be split off if the transition period is during low traffic; or set up some type of procedure or reminder to have LCN maintain a high level of focus to the arrivals on Runway 35. I find that highlighting the aircraft call signs on the STARS display works very well for this. However; when the Runway 35 arrival position; (J); is combined because the demand no longer exists; the highlighted aircraft are landing on multiple runways and it then defeats the purpose. Another solution may be to leave the arrival position J split off as long as any aircraft are landing Runway 35; this way any of the Local control positions can highlight the 'J' traffic to aid in maintaining situational awareness of the arrivals.




Synopsis: MSP Tower Controller reported a conflict when clearing an aircraft while an arrival was within the Arrival Departure Window.