DFW Local Controller described a go around issued by the Final Monitor Controller during triple simultaneous approach procedures to the Runway 17 complex.
Synopsis
DFW Local Controller described a go around issued by the Final Monitor Controller during triple simultaneous approach procedures to the Runway 17 complex.
Narrative
While working Local East 3; I cleared a Saab to land on Runway 17L outside the final approach fix. Due to volume; winds aloft; and wet runways; extra attention was required to ensure that aircraft would be exiting the runway in a timely manner for succeeding aircraft. D10 TRACON was running triple simultaneous ILS approaches on a south flow. While visually ensuring that an AT72 would be clearing the runway; I returned attention to the RACD just as Final Monitor 1 was issuing a traffic alert and 'immediate left turn heading 080' to the Saab for a A300 Heavy who had transgressed from the ILS Runway 17C final approach course at 5;500 and was intercepting the target of the Saab at 5;000. The Saab replied to Final Monitor 1 that the traffic was in sight; was instructed to maintain visual separation from that traffic; and to continue for the ILS Runway 17L approach. Because I was watching my landing traffic and because aircraft were side-by-side for Runway's 17L/17C/18R; I didn't notice that the A300 Heavy had deviated from the final approach course. Recommendation; with the chaos present in the Tower at the time of this event; and my attention on other matters; I would have had to be literally anticipating the A300 Heavy's deviation in order to call traffic to the Saab in a timely manner. I am unable; therefore; to state what my actions would have been; although; certainly; I would have issued the converging traffic to the Saab immediately if I had detected it first. Due to the Saab's position on final; this traffic alert was the responsibility of the Final Monitor; but I wish that I had observed its evolution from the beginning.
Second reporter narrative
Captain pilot not flying; First Officer pilot flying: The winds were 240 at 34 KTS at 5;000 FT. Layered clouds at 700 FT and 1;200 FT and 6;000 FT. While on a 25 mile final to DFW Runway 17C we were turned to a heading of 190 at 6;000 FT and told to intercept the localizer; and cleared the approach. While on a heading of 190 the Controller realized we would not intercept the course fast enough so he told us to turn to a heading of 200 for correction. The aircraft turned on the course normally; land mode was initiated and the 2nd autopilot was engaged. We were switched to Tower. At approximately 5;500 FT while on the glide path and the localizer course the autopilot disconnected. When the autopilot disconnected the Flight Directors commanded a hard right turn; (the heading bug was at 175 degrees) and the LOC deviation showed 1 dot left at that time. The autopilot was reconnected and land mode was reengaged. Approximately 5-10 seconds later at 5;200 the autopilot disconnected again. The First Officer took control of the aircraft and flew manually; trying to correct back to course. We noticed an aircraft displayed on the TCAS which was yellow and 800 FT below and to the left; at the same time TCAS alerted us 'Traffic; Traffic'. I started looking down left to gain sight of the aircraft; as we were currently in VMC; but unable to see the runway. I never was able to see the aircraft or determine the horizontal distance from it. Our vertical estimate was based on the TCAS display. While hand flying the First Officer moderated his descent to gain altitude separation from the aircraft; approximately 5 seconds later the aircraft below us still showed -700 FT and the Controller told us to make an immediate right turn; shortly after the TCAS gave a resolution to climb approximately 300 FPM. A climb and turn was initiated. We discontinued the approach. The Controller initially gave us an altitude of 5;500. We then asked for another vector to circle around and try the approach again. The Controller told us to climb to 6;000 and vectors around were given. The second approach was conducted normally with the autopilot on and no issues were noted.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.