Date: 201711
Local time of day: 1801-2400
Location: MSP.Tower, MN
Flight conditions: VMC
Weather elements / visibility: Cloudy
Light: Daylight
Aircraft: B757 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Climb
Airspace: Class B MSP
ATC / advisory: Tower MSP
Second aircraft: Regional Jet CL65; Undifferentiated or Other Model
Reporter organization: Government
Reporter function: Other / Unknown
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Situational Awareness
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Inflight Event / Encounter Weather / Turbulence
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Executed Go Around / Missed Approach; Flight Crew Took Evasive Action
Contributing factors: Company Policy; Airspace Structure; Procedure
Primary problem: Procedure

Narrative: We were on a converging runway operation. I had gotten off position; after working Local Control with very high wind gusts; not knowing that our wind shear alert system was out of service. I was in the break room at the Tower; which has windows that look out to the west; with an unobstructed view of the departure end of both converging runways. While looking out the window I saw a B757 executing a go around on one runway; with a CRJ that had departed the other runway directly in B757's path. Both aircraft were in extremely close proximity to each other; with ceilings around 4400 feet and a scattered layer around 3800 feet. Our field elevation is around 841 feet; again with extremely gusty wind conditions. I witnessed the B757 veer left initially then jinx hard right to avoid the CRJ. Seconds after that; I no longer could see the CRJ due to that fact that it had climbed into the clouds. The B757 soon also went into the clouds. Both aircraft appeared very close to each other. When we retrieved the data; I believe it came out to around .4 of a mile laterally and 100 feet vertical. This is very close indeed.The converging runway configuration that we use is already a complex and very high workload situation with having to watch an arrival 'safety window' displayed on our radars. We cannot depart an aircraft on the parallels when an arrival is in this displayed window for the converging runway; regardless of speed depicted on our radars. Often times it is worked combined with one controller working both runways during busy arrival and departure banks. I have many times told the supervisor to split these positions from each other but the mind set is to power through it. Controllers are just as responsible for not splitting this position. Many times; you are just a single transmission away (a medivac helicopter calling the tower unexpectedly) from being in an overwhelming air traffic situation; yet these conditions continue; and always have. THIS NEEDS TO CHANGE NOW.With no wind shear equipment working; we should never have been using the converging runway operation at all; and I feel it should be part of the requirements when using this complex procedure of converging runways. Gusty wind conditions are another reason NOT to use converging runways. A stable wind environment is really the only safe way to operate in this configuration.  Also; the ceiling requirement needs to be higher than it is. The two aircraft I mentioned in the event above are an example why. The pilots just barely had time to get visual. IT WAS AMAZING THEY WERE ABLE TO SEE THE AIRCRAFT AT ALL; FOR THEY WERE ALREADY IN A VERY HIGH WORKLOAD SITUATION. In the event I mentioned above they very soon went into the clouds; with what looked like some almost extreme maneuvering prior to entering the clouds.Staffing and splitting control positions in a timely manner also need to happen much more frequently than they currently are. Sure it might be slow at times; but these are few during the day. When the air traffic builds; it builds up rapidly; and controllers need to be on positions; at the ready.




Synopsis: MSP Tower Controller reported they observed conflicting traffic of an aircraft executing a go around and a converging runway departure.