Flight Instructor with student reported NMAC with another aircraft in traffic pattern that was complicated by a congested traffic pattern and busy tower frequency.
Synopsis
Flight Instructor with student reported NMAC with another aircraft in traffic pattern that was complicated by a congested traffic pattern and busy tower frequency.
Narrative
Flight training operation with instructor pilot and student pilot. At the time the Tower Controller was working both Tower and Ground frequencies with 5+ aircraft in the airspace and numerous others calling Ground. Student pilot checked in over the VFR reporting point requesting a full stop landing at the MLB airport. Tower Controller proceeded to reprimand the student pilot for 'stepping on' someone completing a read back. The read back was being broadcasted on MLB Ground; so we had no way of knowing someone else was communicating on Ground frequency as we were monitoring Tower. This is often a problem when the Tower is working both frequencies. The student pilot proceeded to repeat the call to Tower. Tower instructed the student pilot to enter a right base and report a two-mile base for Runway 9R. The student pilot read that back. Approaching a two-mile base the combined frequencies were so busy that we were unable to get a word in to report the two-mile right base. Approaching the extended centerlines for Runways 9L and 9R; the instructor (myself) and student noticed an aircraft on the opposite base heading directly at us. Two aircraft were approaching head on for opposite bases for parallel runways with no traffic advisory by ATC. The Controller seemed task saturated at the moment and multiple aircraft were not receiving clearances until short final. I (the instructor pilot) took over and deviated to the west to avoid a traffic conflict. At this point; we were trying to get in touch with Tower to notify the Controller of our position and that we were deviating for traffic. I got on the radio and called Tower notifying the Controller that we were approaching final for 9L deviating for traffic. Tower proceeded to reprimand us saying that deviation was unnecessary and that we were assigned the parallel Runway '9R'. I then initiated a right turn to reestablish on the final for Runway 9R with the opposing traffic in sight at all times; however this brought us close to the opposing traffic. It was determined that both myself and the student pilot believed we were cleared to approach Runway 9L when we were actually given 9R. At MLB; pilots are used to being given the same runway 95% of the time; so complacency played a role in us assuming we were supposed to approach Runway 9L. Additionally; we were distracted and startled as we were accepting the clearance for right base 9R after we got reprimanded for inadvertently stepping on an aircraft transmitting on a frequency that we were not required to monitor. This disturbance likely interfered with us mentally processing the non-standard approach clearance to Runway 9R. As we approached the two-mile reporting point; the Controller was so busy such that we could not get a word in to confirm our two-mile base and landing clearance. This led to the pressure and distraction that caused our brain's to default to the usual approach clearance to land 9L. To prevent a recurrence; pilots need to be vigilant when assigned approach clearances at VFR airports where they are complacent with getting the exact same clearance multiple times a day. Also; when a traffic conflict is present; pilots need to do everything possible to stay well clear of conflict. Additionally; Controllers should not reprimand pilots unnecessarily during critical phases of flight as this causes significant distraction in the cockpit that heightens the risk of pilot error. To ensure traffic de-confliction; the Controller workload and frequency should not get so busy as to prevent effective communication.
Second reporter narrative
This event started at the visual reporting point for using '9R and 9L' at MLB. We reported at the point and were gripped at for stepping on someone else on frequency. The other aircraft we 'stepped on' was on the Ground frequency so we had no way of knowing as we were tuned into Tower. We then got clearance for 9R and report a 2 mile right base. Once we reached the reporting point the frequency was so busy we were unable to get any word. We continued on our base leg until we noticed another aircraft also on base leg from the other direction; while MLB does have parallel Runways 9R and 9L we got no traffic alerts for this traffic. The instructor took control and attempted to deviate west. The instructor notified Tower and told us to continue to 9R. The instructor then proceeded to intercept the final approach for 9R. During all of this we did come close to other traffic with having them in sight the whole time. We then proceeded to come to 9R where we asked Tower if we were still clear to land but he never gave us a response as the frequency was so busy. We ended up going around and landing on 9L. In order; to prevent situations like this happening again pilots need to make sure that they don't get complacent in critical phases of flight. Also; traffic alerts when 2 planes are both on base legs from opposite directions would be helpful so there is no confusion on where the other plane is going and everyone is going to the right runway.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.