History of Flight
The crew of a Sky North Air Ltd. Beech 100, registration C-GNAA, serial number B 24, was on a re-positioning flight from Thompson to Island Lake, Manitoba. On arrival in the Island Lake area, the crew commenced an instrument approach to Runway 12. On the final approach segment, the aircraft descended below the minimum descent altitude and the crew initiated a missed approach. During the missed approach, the aircraft struck trees. The crew was able to return for a landing on Runway 12 without further incident. The two crew members were not injured; the aircraft sustained damage to its right wing and landing gear doors. The accident occurred during hours of darkness at approximately 2110 Central Standard Time.
On the evening preceding the accident, the crew had been called at about midnight for a medical evacuation flight to Winnipeg, after which they returned to Island Lake. They were released from duty at approximately 0700 on the morning of the accident. They were called at about 1900 later that day for another medevac flight to Thompson and return. The occurrence flight departed Thompson for Island Lake at 2020.
The 2100 routine weather observation at Island Lake was: wind 150° true at 7 knots, visibility 2 statute miles in light snow, ceiling broken cloud at 2000 feet agl, overcast at 5000 agl, temperature -17°C, dew point -20°C, altimeter 29.72 inHg.
The crew chose to fly a straight-in RNAV 12 instrument approach. The first officer was pilot flying; the captain was pilot not flying. The crew did not calculate a cold temperature correction for minimum safe altitudes.
At 35 nm from the airport, the captain armed the approach on the GPS. The aircraft crossed the REVEK initial approach fix at approximately 3000 feet asl and intercepted the inbound track of 121°. At UKUGA (5 nm from the runway), the aircraft was at 1500 feet asl, and the captain set an MDA of 1200 feet asl in the altitude alerter, applying an estimated altitude correction of about 40 feet. The landing gear was selected down and flaps were set progressively. At approximately 3 nm from the runway, flaps were set to 60%.
The captain briefly looked outside to see if the runway environment was visible, missing calls for '100 feet above' and 'at MDA'. When he refocused on instruments, the aircraft was at 1000 feet asl (200 feet below MDA). The aircraft descended further to 900 feet asl; the captain took control and initiated a missed approach. While climbing, the aircraft struck trees at approximately 840 feet asl, about 2.5 nm from the runway threshold, with its right wing and landing gear doors. The aircraft climbed to 2000 feet asl and landed on Runway 12 without further incident.
Flight Crew
The flight crew were certified and qualified. The captain had about 3200 hours total flying time, with 500 hours on type, and had been with SkyNorth for about eight months. The first officer had 1200 hours total, with about 620 hours on type, and had been employed for about seven months. The crew's work schedule was 5 days on with 4 days off away from base. They had the required rest period but found it difficult to sleep at company accommodations. There is insufficient information to suggest fatigue was a factor.
Pilot Training
SkyNorth operated two Beech 100s and one Piper PA-31 Navajo Chieftain. It did not have a formal training department; training was overseen by the chief pilot. The ground training was web-based and comprehensive. SkyNorth did not provide simulator training; flight training was conducted in actual aircraft. The CARs required captains to have a pilot proficiency check (PPC). SkyNorth hired pilots with or without a current PPC. New captains received 25 to 50 hours of supervised line flying on revenue flights before regular duties. First officers received a pilot competency check from the chief pilot, followed by line flying. SkyNorth was not approved to conduct RNAV approaches, so its pilots were not trained per subsection 723.98(21) of the Commercial Air Services Standard.
Aircraft
The aircraft was certified, equipped, and maintained per regulations. It was not equipped with a cockpit voice recorder or flight data recorder, which were not required. The altitude alerter had a loud continuous tone upon reaching 1000 feet above the selected altitude; a switch had been installed to silence it, which had become normal practice. The captain's altimeter was a counter drum-pointer type; the first officer's was a three-pointer analog type, which studies have found to have a higher potential for misreading. The GPS unit was a KLN 90B certified for en route IFR but not approved for IFR approaches; it was located in the center panel, outside the normal scan, and not integrated with primary flight instruments.
Company Procedures
SkyNorth's SOPs described a non-precision approach profile. The approach profile specified steps for flap setting, altitude alerter calls, gear extension, and callouts at 100 feet above MDA and at MDA. The SOP required the PF to respond with 'go around' upon hearing 'minimums'.