Fairbanks, AK, USA
N121WV
BEECH 1900C
N4112K
PIPER PA-31-350
An air traffic control operational error and near midair collision occurred between a Raytheon Beech 1900 and a Piper Navajo about 3.5 miles west of the airport. The Beech 1900 was northeast bound toward the airport descending to enter the traffic pattern for runway 20L, while the Piper had just departed from runway 20R and was climbing on a westbound heading. Both airplanes were operating under visual flight rules at the time of the incident, and were receiving air traffic control services from a tower air traffic controller. There were no reports of injuries or damage to either airplane. The local controller, who had only been certified on the position for 5 weeks, stated that she was trying to establish vertical separation between the two airplanes by restricting the departing Navajo to remain at or below 2,000 feet. The Beech was still on the approach controller's frequency, so the local controller was not aware of what instructions had been issued to the pilot. The approach controller mistakenly believed that the Beech was in communication with the local controller. Neither the local controller nor the controller-in-charge, who was responsible for monitoring the operation and assisting the local controller, initiated any coordination with the approach controller to resolve the conflict. NTSB review of local procedures and directives found that there was a misunderstanding of required procedures and controller responsibilities for operations in Terminal Radar Service Areas, including separation standards and procedures for transfer of communications between controllers.
SUMMARY On June 14, 2011, at about 1310 Alaska Daylight Time (ADT), Warbelow’s Air Ventures flight 401 (WAV401), a Raytheon-Beech 1900, experienced a near mid-air collision (NMAC) with Era Alaska flight 12K (ERR12K), a Piper Navajo. Both aircraft were operating under visual flight rules at the time of the incident. WAV401 was in contact with the West Radar (WR) position of Fairbanks TRACON (FAI), and ERR12K was being handled by the FAI Airport Traffic Control Tower (ATCT) local control (LC) position. WAV401 was a scheduled 14 Code of Federal Regulations (CFR) part 135 passenger flight operating from Galena, Alaska, to Fairbanks, with 2 pilots and 5 passengers. ERR12K was an on-demand 14 CFR part 135 charter flight operating from Fairbanks to Minto, Alaska, with 1 pilot and 4 passengers. There were no reports of injuries or damage to either aircraft. The incident occurred 3.5 nautical miles southwest of the Fairbanks International Airport at approximately 2,100 feet. WAV401 was northeast bound toward the airport descending to enter the traffic pattern for runway 20L and was receiving radar service from FAI approach control. ERR12K had just departed from runway 20R, was climbing on a westbound heading, and was in communication with FAI tower. The tower controller noted the potential conflict between the two aircraft and issued three traffic advisories to ERR12K, but the pilot never reported seeing WAV401. The approach controller issued no traffic information to WAV401 about ERR12K. Immediately after the aircraft crossed paths, the pilot of WAV401 reported that a Navajo had passed 100 feet above their aircraft. The approach control then instructed the pilot of WAV401 to contact the tower. After landing, the pilot of WAV401 requested telephone contact information for the tower. The incident was reported as a NMAC by the chief pilot of Warbelow’s Air Ventures about two hours later. In their statements, the crew of WAV401 reported descending to avoid the ERA aircraft. The airspace surrounding Fairbanks is designated as a Terminal Radar Service Area (TRSA). In a TRSA, controllers are required to ensure that aircraft targets do not merge unless the aircraft have a minimum of 500 feet vertical separation or can maintain visual separation, although visual separation was not being applied in this incident. Review of radar data for WAV401 and ERR12K indicated that their radar targets merged with approximately 200 feet of vertical separation. On June 18, the FAA reported two operational errors as a result of this incident: one for a loss of separation between ERR12K and WAV401, and a second for a minimum vectoring altitude violation involving ERR12K when the aircraft was assigned at or below 2,000 feet in an area where the minimum assignable altitude was 2,900 to 3,700 feet. 1. History of Flight The pilot of WAV401 first contacted the FAI West Radar approachcontroller at 1259:32, descending through 12,000 feet for 7,000 feet. The controller acknowledged the transmission and provided wind and altimeter information for FAI. At 1302, a position relief briefing began at the West Radar position, and continued until 1305:22. While the relief briefing was in progress, the controller cleared WAV401 to descend to 5,000 feet and to fly heading 045. At 1302:58, the pilot of WAV401 canceled their instrument flight rules flight plan. The controller then instructed the pilot to maintain visual flight conditions and enter right downwind for runway 20L. The pilot acknowledged. At 1310:06, WAV401 transmitted, “Approach, 401 – we just had a Navajo fly over the top of us. We’re going to switch to tower now. We never got the call.” The controller responded, “…sorry, I thought I switched you, you can contact tower.” The pilot of ERR12K first contacted the FAI local control position at 1302:11, and reported ready in sequence for departure from runway 20R. At 1306:06, the local controller cleared ERR12K for takeoff, and instructed the pilot to turn right on course. At 1307:15, the pilot of ERR12K requested to climb on course. The local controller asked what the on-course heading would be, and the pilot responded, “278.” The controller approved the on course heading, and advised the pilot of traffic, “…a B190 [Beech 1900] inbound seven miles to the southwest at 3,000 for…landing on the left.” The pilot replied, “…looking for the Beech ERR12K.” At 1309:12, the controller transmitted, “ERR12K Beech 1900 traffic ahead to your right two miles, 2,700, correction ahead to left about 11 o’clock.” The pilot of ERR12K again responded that she was looking for the traffic. At 1309:24, the controller instructed the pilot of ERR12K to maintain at or below 2,000 feet. The pilot responded, “OK, then I will be going north for a little while.” At 1309:49, the local controller provided another traffic advisory to ERR12K, describing WAV401’s position as, “…ahead and to your left about half mile 2,300, Beech 1900.” The pilot then requested a right 360 degree turn. At 1310:16, the local controller canceled the altitude restriction and instructed ERR12K to again proceed on course. At 1310:24, WAV401 contacted the local controller, reporting, “…we just got switched over to you now, we got the PA31 [Navajo] in sight.” As WAV401 entered the pattern there were some sequencing issues with aircraft not involved in the incident. After the landing sequence was established, the aircraft landed safely. The pilot of WAV401 called the tower after landing to discuss the incident with the CIC. The call was not recorded, but when the pilot reported the incident he initially declined to file a near midair-collision (NMAC) report. The chief pilot of Warbelow’s Air Ventures called the tower about two hours later and did file a NMAC report. 2. Radar Data Radar data for this incident was obtained from the ASR-11 radar system located near Fairbanks airport. The radar data file has been entered in the docket. PERSONNEL STATEMENTS The pilot of WAV401 provided the following statement via Warbelow’s Air Ventures: I was the Captain (PIC) of flight 401 from Galena to Fairbanks on June 14, 2011, with a copilot (SIC.) Approximately 15 miles west of the field, we canceled our IFR clearance and were told by FAI approach to enter the right downwind for 20R. Upon entering downwind just abeam the FAI VOR, the copilot, who was flying the plane, said "oh ****!" and immediately initiated a descent. I looked out his windshield and saw an ERA PA-31 in a right bank approximately 100 to 150 feet above us. I queried the controller that we had just had another aircraft pass over the top of us, and he said he did not have the aircraft on radar. I asked if he wanted us to switch to tower, which he replied that he thought he had, but the copilot confirmed to me he had not. (The controller had been busy trying to keep two VFR [aircraft] separated northwest of the airport.) Upon switching to tower frequency, we overheard "12K traffic no factor and continue the turn on course.” This was the aircraft that had flown over us. We were cleared to land by the tower controller, and while on base over the University, were told to continue northbound to follow a Cessna 152 on a 2 mile base. Seeing this traffic moving from our 11 to 12 o'clock position, I took the controls from the copilot and started the northbound turn. Several planes were in the pattern for 20L, and confusion on who was to be following whom. I told the controller we would continue the left turn and be able to land on 20R. After clearing the runways, I asked for the tower phone number and [was] given the supervisor's initials. When I called the supervisor, he apologized for the mix-up on the landing sequence and said the controller was new. I told him that wasn't my concern, but the near midair was. He was unaware of any separation conflict, and I had to explain what had happened. I was told ERR12K had been cleared for takeoff on 20R, but because of another ERA aircraft being cleared to land on 2L, was told to turn westbound after takeoff. This of course, is the direction we were entering the downwind from. I suggested to the tower supervisor that maybe too many opposite direction takeoff and landings were being granted with "summer only" pilots and student pilots in the pattern, as a possible fatal accident nearly occurred with long time commercial pilots flying near the airport. FAI Controller in Charge (CIC) The CIC stated that around the time of the incident the tower workload was moderately busy, with some complex operations. The only activity around the tower that might have been a distraction was that there were some Technical Operations people working on the catwalk just outside the tower windows. He also noted that there were an inordinate amount of phone calls coming into the tower that day, many of which were administrative in nature and had nothing to do with air traffic control. The CIC was monitoring tower operations from the position next to the Automatic Terminal Information Service (ATIS) machine and working with the local controller on “the crossover”, which is how he referred to the procedure that resulted in the NMAC. The CIC stated that normally departing aircraft were instructed to fly runway heading after departure. However, when ERR12K departed, runway heading was not usable because another aircraft was inbound to the airport from the south. He felt that giving an intermediate heading on departure would have worked well in this situation, but that at FAI the only two options that seem to be utilized were to fly runway heading or proceed on course. The CIC was aware of the conflict and assumed that the approach controller was keeping WAV401 high for some reason. The local controller tried to establish 500 feet of vertical separation. He heard her make repeated traffic calls and felt that she was mitigating the conflict as best she could considering that she did not have communications with WAV401. He believed that WAV401 was well above ERR12K when they passed. There was no coordination between tower and approach. The CIC stated that this was a mistake on his part, in that he should have called approach and coordinated. The CIC recalled the pilot of ERR12K saying that she needed to do a 360 degree turn. As he watched, it appeared that ERR12K and WAV401 would cross over with WAV401 well above ERR12K, and he believed they had until receiving the call from the pilot of WAV401 after landing. The CIC said he was not aware that an operational error (OE) had occurred. He said that appropriate separation was 500 feet vertical or visual separation, and he thought WAV401 had been level at 2,500 feet for quite a while and that was why the local controller gave ERR12K an altitude restriction to maintain at or below 2,000 feet. The CIC stated that he was never aware that either pilot thought their aircraft had passed too closely until later when the pilot of WAV401 called the tower. When asked what a safety alert was and why one hadn’t been issued in this case, the CIC stated that a safety alert was a last resort to warn a pilot of a potential collision or imminent contact with another aircraft if something wasn’t done. The CIC felt that the local controller probably didn’t issue a safety alert because it visually appeared that the aircraft would pass with adequate separation, and that WAV401 descended unexpectedly after remaining at 2,500 feet for such a long time. The radar data tags were overlapping, and the controllers couldn’t read the altitudes on the tower radar display. The CIC was aware that the local controller had only been certified a short time, but he had not worked with her a lot and was not familiar with her overall performance. He felt that he was generally supervising rather than coaching, or keeping a closer eye on her as a newly qualified controller. When asked about the difference in services provided to aircraft in a TRSA and in Class D airspace, the CIC stated that there was no difference in services provided except that tower visual separation could be applied in Class D airspace. The CIC described the general responsibilities of his position as general supervision, maintaining good traffic flow, monitoring local control to ensure separation, and being a second set of eyes. He noted that the CIC is responsible for handling operational calls such as notifications of airspace status, outages, etc, but is also required to answer and reroute administrative calls that really shouldn’t come to the cab. There are direct lines to the tower cab, TRACON and administrative area, but 75% of the calls taken in the tower cab are routed to the supervisor’s desk downstairs. When asked what was discussed during the phone call from the pilot of WAV401, the CIC stated that he first started out apologizing to the pilot for the pattern sequencing issues since he assumed that was the reason for the call. The pilot then stated the reason for the call was how closely ERR12K had flown over his aircraft. This was the first time the CIC realized that there was an issue with a possible NMAC, so he asked the pilot if he wanted to file a NMAC report and the pilot responded no. The CIC stated that he did not make a quality assurance review entry into the log about the event because the pilot did not ask to file a NMAC report or express any concerns about the sequencing. The CIC estimated that only 15% of requests for opposite direction operations were denied. He stated that opposite direction operations were often solicited by the tower, but did not recall any Standard Operating Procedures (SOP) addressing their use. When asked if he had any recommendations, the CIC stated that recorded position relief briefings were far too long and laborious, so much so that it would be easy for a controller to forget the first thing mentioned in the briefing by the time it is finished. This could have been the reason that WAV401 was never switched to the tower, because the fact that he was still on frequency was the first item in a very long relief briefing. When asked about strip marking, the CIC stated that flight strips were not a requirement at FAI. The CIC did not recall receiving any training on D-BRITE usage or operations within a TRSA. FAI Ground Controller (GC) At the time of the incident, the ground controller was assisting another controller trainee with familiarization on the functions of the position, and was not closely monitoring the activities at the local control position. She was aware that after landing, the pilot of WAV401 called and spoke with the CIC about something that happened during the flight. Sometime later the chief pilot from the company called the tower as well. When asked about TRSA procedures, the ground controller stated that required separation was either visual, 500 feet vertically, or "green between.” (Target resolution.) Aircraft were typically assigned runway heading until being allowed to turn on course. Radar separation was required throughout the TRSA. However, tower controllers used different methods to apply separation, because they were not operating as radar controllers. It was normal practice for local controllers to retain aircraft on their frequency until all conflicts were resolved, and to then transfer communications to the departure controller. The ground controller stated that, as a tower controller, she would never advise a pilot of radar contact. The departure controller does that. She stated that it was common for inbound aircraft to enter the class D airspace without first establishing communications, but not so much for aircraft that had been working with the approach controllers. Various issues could cause communication difficulties. If an aircraft approached the airport without establishing communications, the ground controller noted that controllers would be required to use the light gun to communicate clearances. Controllers at FAI were given a minimum vectoring altitude (MVA) test during training. The ground controller stated that at various points in training controlle
Inadequate air traffic control actions that failed to establish and maintain required separation between the two airplanes. Contributing to the incident was inexperience on the part of the local controller, inadequate oversight by the tower controller-in-charge, and deficient facility procedures and training.
Source: NTSB Aviation Accident Database
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