A Transportation Safety Board investigation, released Thursday, warns of a continued increased risk of similar collisions because there is no special use advisory airspace (CYA), found in “other busy flight training areas,” near Sault Ste. Marie.
“A CYA has defined dimensions, and can have restricted times, altitudes, frequencies, and entry restrictions,” a TSB report reads. “A CYA is displayed on all published maps, is known to ATC (air traffic control), and can be depicted on the controller's radar displays. If maneuvers related to flight training take place in controlled airspace that is not specifically designated for such training or known to ATC, there is an increased risk of collision, as these types of maneuvers can be difficult for controllers or the crews of conflicting traffic to anticipate.”
Colin Kirkwood, dean of environment, technology and business, said safety is “first and foremost in this program.”
“We take it very seriously,” he told The Sault Star on Friday.
A Sault College Zlin 242 was on a training flight southeast of Sault Ste. Marie Airport on Sept. 3, 2014. A student pilot and instructor planned to practice steep turns, stalls and spins.
At the same time, a Jazz Aviation de Havilland Canada DHC-8-102, with three crew and 34 passengers aboard, left the Sault airport bound for Toronto.
The craft's traffic alert and collision avoidance system warned the flight crew, then flying at 4,000 feet, that the Zlin was three nautical miles ahead, and 1,000 feet above, the de Havilland. A pilot and first officer visually saw the training aircraft seconds later. When the DHC-8 levelled off at 4,500 feet, the Jazz crew saw the Zlin at 5,200 feet. The training craft began a fast descending turn that “put the two aircraft on a collision course,” the TSB report reads.
The planes were in airspace near Dafter, Mich., about 20 kilometres south of Sault Ste. Marie, Ont.
The DHC-8's traffic alert and collision avoidance system gave a voice instruction for the flight crew to descend. The pilot determined, due to the Zlin's flight path, a descent alone “would not be sufficient.”
The DHC-8 flight crew took evasive action shortly before 4 p.m., banking the aircraft 30 degrees to the left. The Zlin passed on the de Havilland's right side. The student banked the Zlin sharply to the left. The two planes were about 350 to 450 feet apart.
“That's quite a dangerous distance,” given the speed the planes' speed and the variability of the spinning Zlin, said Ewan Tasker, TSB investigator in charge.
An air traffic controller in Toronto, overseeing three other aircraft in the Sault Low sector, saw no conflicting traffic and had approved the de Havilland's departure from the Sault airport.
The controller knew of Sault College's flight school, the TSB says, and from experience aircraft close to the airport were “much lower” than 5,000 feet.
“This expectation may have resulted in the aircraft target's altitude going unnoticed,” the report says.
Other possible factors include the brightness of the monitor used by the controller in Toronto was on the minimum setting and a “clutter” of aircraft in the Sault area.
“It didn't click to him initially that it would be a conflict,” said Tasker. “If he had seen and acknowledged both aircraft and their altitudes, clearly he wouldn't have put them on a course that conflicted with each other.”
The incident happened in Class E airspace where there is no requirement to contact air traffic control in Toronto, or monitor for instrument flight rules traffic. That's why the student and faculty member didn't hear the go-ahead given by Toronto flight control center to the Jazz crew.
“Hearing the clearance may have alerted the C-FANU (Zlin) to the possible conflict,” the TSB says. “Given their experiences with previously completing upper airwork in the area without conflict, the student and instructor did not anticipate spotting a departing IFR aircraft during their scan of traffic in the area prior to the spin.”
Faculty and students who fly had to sign off on a printed memorandum distributed at the college on Dec. 10, 2014. Changes in flight protocol included:
- alerting the Sault tower once within 10 nautical miles of the control zone if, or when, spins are being done;
- not to do spins within the departure or approach paths of surrounding area aerodromes, including Chippewa County International Airport, Sault Ste. Marie, Mich., Municipal Airport, Bar River and St. Joseph Island;
- contact Toronto center control when doing exercises in the VOR area.
“It's a serious matter for us and we take the steps necessary to make sure that everybody's informed,” said Kirkwood.
Special use advisory airspace for training aircraft can be requested by air traffic control or training schools such as Sault College, said Tasker. Transport Canada “sometimes just determines a need,” he added. Kirkwood could not confirm if the college has ever requested such a designation.
Fatigue and weather were not factors in the incident. All pilots and controllers “were certified and qualified for their respective positions.” The Sault College instructor had about five years experience and 1,025 hours of flight time. The student, with 300 hours of flight time, had about three years of flight experience.
The TSB probed the incident “for the purpose of advancing transportation safety.” It's not the agency's role to assign fault or determine civil or criminal liability.
“We leave it with the people who hold the cards, if you will, to do whatever they think is necessary to reduce the risk,” said Tasker in a telephone interview from Richmond Hill, Ont. “We're all trying to advance safety and prevent this from happening again. We're not going to do that by punishing people. We need to find out why this happened to prevent the next guy from doing it again. None of these people wanted to do this. No one was acting recklessly. No one was doing anything untowards.”
The three-year aviation flight-technology, with enrollment of about 200 students, is one of Sault College's flagship programs. The program has a fleet of 11 Zlin 242Ls and two Piper PA-44-180 Seminoles.
- Source: http://www.saultstar.com
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