Date: 201911
Local time of day: 1201-1800
Location: CLT.TRACON, NC
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 170/175 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class B CLT
ATC / advisory: Tower CLT
Second aircraft: Super King Air 350
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Human-Machine Interface; Situational Awareness
Anomaly: ATC Issue All Types; Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Executed Go Around / Missed Approach; General Flight Cancelled / Delayed
Contributing factors: Airport; Company Policy; Human Factors; Procedure
Primary problem: Human Factors

Narrative: Throughout the push I mentioned to the supervisor that the final was running aircraft to tight in order to try to get more room. Throughout the push I had to prep aircraft to plan for minimal time on the runway. King Air touched down and immediately slowed on the roll out. I transmitted to King Air to keep the speed up on the roll out and that traffic was on a half mile final. Aircraft replied and increased his speed. I observed on the ASDE (Airport Surface Detection Equipment) the ground target turning off the runway at the first high speed. At the same time the landing aircraft; EMB-175 which was not to the threshold yet; pitched up. EMB-175 then transmitted that he was going around. I issued go around instructions to EMB-175 and the pilot accepted those instructions.Immediately after the supervisor on duty said 'he was committed to go' which I agreed on. It was clear the EMB-175 was committed to go around not knowing what the outcome was going to be. We also discussed that we both saw on the ASDE the aircraft start his turn to exit the runway. 15 minutes later the operations manager called upstairs to say the aircraft was not clear. After discussing with the operations manager and looking at the replay you could see that the King Air even though committed and clearly exiting the runway was not completely clear of the runway when the EMB-175 was crossing the threshold. Considering our viewpoint and not fully seeing the turnoff it would have been impossible to see this outcome and to have been able to see that the aircraft was not fully clear.Multiple things could have been done to prevent this. More room on the final. A tight final on the west runway has become the norm and unfortunately less than 2.5 miles has become a standard at the threshold; not the exception. The airport needs to install 2 more high speed turn offs on the west runway giving smaller and slower aircraft a chance to exit the runway sooner. The new Tower being built will hopefully give us a better view point to be able to see if aircraft are truly clear and not have to rely on the ASDE as much for separation. In this situation it would have been less safe to send the EMB-175 around in such a critical phase of flight for just the 'possibility' that the King Air was not clear of the runway. In order to prevent this kind of situation without having the tools to see if an aircraft is truly clear we would need to send 20% of aircraft around because of a unknown or we need more room on final; or more high speed turn offs.




Synopsis: CLT Tower Local Controller reported an aircraft on short final initiated a go-around due to landing traffic not being completely clear of the runway.