Gulfstream IV / G350 / G450
Air Traffic Control Fully Certified
Other / Unknown; Situational Awareness; Communication Breakdown
ATC Issue All Types; Conflict Ground Conflict; Less Severe
Air Traffic Control Issued New Clearance; Flight Crew Executed Go Around / Missed Approach
Procedure; ATC Equipment / Nav Facility / Buildings; Weather
I was working Local one and two combined. Runway 17R departure windshear alerts off and on. Air Carrier Z waited in position for windshear with Aircraft X on final. Windshear no longer indicated with Aircraft X on a 10 mile final. Air Carrier Z and Air Carrier W depart. Air Carrier Y was given takeoff clearance with Aircraft X on a 4 mile final. Then a Runway 17R departure windshear alert goes off and Air Carrier Y refuses takeoff. I try to get Air Carrier Y off the runway and I messed up the call sign. I again try to get Air Carrier Y and ultimately have to send Aircraft X around.Recommendations to prevent reoccurrence would be to not use a runway with windshear for mixed operations. I would like to use this space on the form to write a narrative for contributing factors. I have witnessed numerous wind shear alerts in the Tower cab that pilots do not concur with more often then not. I have notified numerous supervisors and they have made phone calls about it and nothing has happened. A common phrase in the Tower cab is Runway 26 windshear alert 25 knot gain 2 mile final previous 15 arrivals did not experience it. Or Runway 17R departure windshear alert 20 knot gain on the runway the airbus on climb out did not experience it. While the event with Aircraft X could have been handled a lot better; I would like to take this opportunity to report this equipment's problems to someone outside of the facility so we will not continue business as usual; and with the equipment contributing to a go around with an air carrier on the runway hopefully it becomes a priority. In the hour on position not one pilot encountered the report on the LLWAS.
DEN Tower Controller described a go around event resulting from a departure delaying takeoff due to a windsheer alert. The reporter recommended limited use of 'mixed operations' when windshears are active.