Preliminary Report: Turboprop Single Crashes from High Altitude
Daher-Socata TBM 850, 75 miles west of Ottawa, Canada, Oct. 8, 2012–A TBM 850 spiraled from FL270 and struck the ground near the Canadian city of Calabogie, Ontario. The 26,000-hour pilot, also a flight instructor and the only occupant, was killed in the crash. The aircraft was brand new and registered on Sept. 18, 2012. The reason for the spiral has not yet been determined.
Preliminary Report: Twin-Turboprop Crash Kills 19 in Nepal
Dornier Do-228, Kathmandu-Tribhuvan airport (VNKT), Nepal, Sept. 28 2012–A Dornier Do-228 operated by Sita Air crashed just after takeoff from Kathmandu-Tribhuvan Airport in Nepal. All 16 passengers and three crewmembers perished in the accident. A Sita Air spokesman told local media that the aircraft caught fire after a bird strike thought to involve a large vulture. The aircraft crashed on the banks of the nearby Manohara River.
Preliminary Report: Jet Crash Leaves Unlicensed Pilot in Coma
Learjet 24, Bornholm Airport (EKRN), Denmark, Sept. 15, 2012–A German-registered Learjet 24 flown by an unlicensed pilot crashed near the airport (EKRN) on the Danish island of Bornholm at the conclusion of an IFR flight from Strausberg Airport (EDAY), Germany. The accident occurred in day VFR conditions and seriously injured the pilot and passenger. The aircraft was destroyed when it came to rest in a cornfield short of the runway. At press time, the pilot remained in a coma in a Danish hospital.
During the preliminary accident investigation, German authorities informed the AIB DK (Danish Accident Investigation Board) that the pilot did not hold a valid German pilot certificate. The passenger aboard was not a pilot, so the aircraft was operated in violation of its certification, which requires two pilots aboard the aircraft. Shortly before the accident, the pilot declared an emergency three different times. The Danish accident report said the “wreckage and the wreckage trail pattern were consistent with a low forward airspeed and a steep descent stall.” Investigators also found four of the aircraft’s five fuel tanks empty. While the fuselage tank did contain 42 gallons of fuel, the fuel transfer and crossfeed valves were not set to make any of the fuel useable. German aviation authorities also said the Learjet’s registration had been cancelled in 2009 and that the latest valid airworthiness certificate expired in March 2005.
Preliminary Report: Helicopter Crashes on Positioning Flight
Eurocopter AS355F1, West Windsor, N.J., Sept. 15, 2012–The sole-occupant pilot was killed when the helicopter struck the ground during a VFR flight from Princeton Airport (39N) to Atlantic City International Airport (ACY). The helicopter’s transmission, removed June 4 for repair work, had been reinstalled three days before the crash. The operator said that a test flight after the repairs revealed no problems, and that the helicopter had flown one hour 10 minutes since reinstallation of the repaired transmission.
Approximately five minutes after the TwinStar lifted off from Princeton, McGuire Approach Control, previously in communication with the TwinStar pilot, lost radar and radio contact. Witnesses near the crash site reported seeing a flock of small birds strike the helicopter, as well as seeing something fall from the machine before it spiraled into the ground and caught fire. Another witness recalled hearing grinding and popping noises from the helicopter before it crashed. The TwinStar’s rotor head was located approximately 100 yards from the main wreckage.
Preliminary Report: Turboprop Experiences Uncommanded Maneuvers
Bombardier Dash 8-100, near Anchorage International Airport (ANC), Alaska, Sept. 5, 2012–The crew of a Bombardier Dash 8 operated under Part 121 by ERA Alaska in daylight IFR conditions experienced an uncommanded left turn, as well as an uncommanded descent from 12,000 feet after departure from Anchorage’s Ted Stevens International Airport. The crew recovered control of the aircraft at 7,000 feet and landed safely back at Anchorage. No one aboard the aircraft was injured.
Preliminary Report: Tailboom of Helicopter Separates in Flight
Bell 407, 22 miles southeast of Elmira, N.Y., Aug. 31, 2012–A Part 91-operated Bell 407 flown by the New York State Police was substantially damaged during a forced landing into wooded terrain after the tail boom and tail rotor separated in flight. The pilot of the surveillance flight, which originated from Genesee Airport (GVQ) in Batavia, N.Y., said he was cruising at 100 knots and 2,500 feet when the helicopter suddenly began to pitch and yaw. The pilot attempted to respond with appropriate input before the helicopter suddenly pitched severely nose down and began to spin to the right. The pilot saw a portion of the tail boom, tail rotor and tail-rotor gearbox falling away from the helicopter. The pilot, who holds a commercial certificate, managed to enter a successful autorotation to the ground.
The sky was clear at the time of the accident, with 10 miles visibility and southwest wind at 10 knots.
Final Report: Helicopter Lost Main Rotor Returning from North Sea Oil Platform
Eurocopter AS332L2 Super Puma, 11 nm northeast of Peterhead, Scotland, April 1, 2009–A fatigue fracture of a second-stage planetary gear resulted in the catastrophic failure of the main rotor gearbox on the Bond Helicopters-operated Super Puma that crashed into the North Sea on April 1, 2009, according to the UK’s Air Accidents Investigation Branch. Maintenance performed on the Puma approximately 36 flight hours before the accident and some of the OEM-installed chip-detection equipment were contributing factors. All 14 passengers and the two pilots were killed when the helicopter hit the water at high vertical velocity. The weather in the crash area reported by other pilots included no clouds below 3,000 feet, good visibility, smooth air and calm seas. The Super Puma was equipped with a digital flight data and cockpit voice recorder system.
The helicopter was on a return trip to Aberdeen from the Miller oil platform approximately 80 nm into the North Sea. Passengers told investigators that five to 10 minutes before the helicopter landed inbound to the platform they heard noises that they assumed were coming from the helicopter’s air conditioning system and not serious enough to mention to the crew.
After refueling, the Super Puma headed southwest toward Aberdeen, climbing to 2,000 feet. Twenty minutes out from the destination, the captain and copilot both made Mayday calls on the en route ATC frequency. A witness near the crash site saw the helicopter descending rapidly before hitting the water. A company helicopter appeared overhead the site within minutes of the accident and found only wreckage and bodies floating in the water, with no signs of life. The main rotor blades, still attached to the rotor head, were located 100 meters away from the main wreckage.
The flight recorders, retrieved three days after the crash, included a health and usage monitoring system (Hums) that delivered data on the state of the helicopter’s rotors, transmission assemblies and engines. The system also included seven magnetic chip detectors, six of which were connected to the Hums. A week before the accident, the chip detectors recorded no activity, but by the time of the accident the chip count had reached 667. An anomaly prevented the chip information from being downloaded from the Hums to ground stations.
Shortly before the accident, the flight data recorder reported the helicopter’s engine and flight parameters were normal, but chip detector warnings began to illuminate three minutes before the accident. Just before the CVR cut off, the main rotor gearbox (MGB) low oil pressure light also illuminated as the pressure dropped to nearly zero in one second. The helicopter left level flight with parameters recorded beyond its design limits. The final Mayday transmission was recorded 20 seconds after the MGB light illuminated.
In addition to the fatigue crack detected in the second-stage planetary gear, the AAIB also found fault with actions taken following discovery of a magnetic particle on the epicyclic module chip detector on March 25, 2009, 36 flying hours before the accident. For reasons undetermined, the metal particle was not recognized as an indication of degradation of the second-stage planetary gear. After March 25, 2009, the existing detection methods did not provide any further indication of the degradation of the second-stage planetary gear. The ring of magnets installed on the AS332L2 and EC225 main-rotor gearboxes reduced the probability of detecting released debris from the epicyclic module, which was the only indication of the degradation of the second-stage planetary gear. The Super Puma does not alert the pilots to an epicyclic module warning. Manufacturer maintenance recommendations to Bond were not carried out, possibly due to miscommunications via e-mail.
The AAIB generated 17 safety recommendations at the conclusion of its Super Puma investigation, most of them focused on additional maintenance inspections of the Super Puma main gearbox. They also recommended adding an epicyclic module warning light visible to Super Puma pilots.
Final Report: Twinjet Pilot Flew Unstabilized Approach
Dassault Falcon 10, Toronto Buttonville Airport (CYKZ), Canada, June 17, 2011–The Transportation Safety Board of Canada (TSB) found the pilots responsible for losing directional control of a Falcon 10 operated by Skycharter immediately after touchdown at Toronto Buttonville Airport.
The captain, the pilot flying, flew an unstable high-speed approach during a six-minute trip between Toronto’s Lester B. Pearson International Airport (CYYZ) and Buttonville. The TSB cited the 12,000-hour captain for failure to follow company standard operating procedures, his commitment to land during the first approach, his decision to ignore a number of aural GPWS warnings and his violation of a number of Canadian regulations related to speed restrictions in controlled airspace. They cited the first officer for failing to warn the pilot in a tone of voice consistent with his concerns about the unstable approach.
Shortly after takeoff from Pearson, the departure controller amended the Falcon’s clearance to remain at 4,000 feet. While the first officer left the frequency to listen to Buttonville’s ATIS, the captain allowed airspeed to build to 270 knots. Two minutes after takeoff, departure control cleared the flight down to 3,000 feet. The captain had difficulty communicating with ATC and allowed the speed to increase to 290 knots groundspeed as the aircraft approached within six miles of Buttonville. Ninety seconds before touchdown, YYZ departure cleared the aircraft for a contact approach to Buttonville’s Runway 33 when it was descending through 2,600 feet at 230 knots.
Just over a mile-and-a-half from the runway threshold, the aircraft was still showing 220 knots across the ground on radar as the pilot tried to widen his final turn to the right, flying through the final approach to decelerate. He turned at bank angles in excess of 30 degrees in an attempt to line up on final. Thirty seconds before touchdown, the GPWS sounded a “Pull up” alert. The first officer suggested in a low tone of voice that they should go around. The captain acknowledged, but he continued the approach and ignored a second GPWS alert. At 300 feet agl the captain called for full flaps, entered a steep left turn in a bid to regain the runway centerline and ignored the first officer’s request to add more power.
According to Skycharter’s SOPs, the airspeed for a VFR pattern should be 160 knots on the downwind leg, 140 knots on the base and Vref plus 10 knots on the final approach. Before takeoff on the mishap flight, the crew determined that Vref was 117 knots. The aircraft was cleared to fly directly to CYKZ and joined the pattern on base leg. At this point, the aircraft’s calibrated airspeed was 186 knots.
The aircraft touched down hard on Runway 33 and immediately left the runway surface at a speed estimated to be less than 110 knots. Braking and steering were nearly impossible in the grass. The aircraft crossed hard-surface taxiways but for too brief a time for the brakes to be of any use. After the leading edge and its slats were damaged by striking airfield signs, the aircraft came to a stop in the grass and the captain shut down the engines. Both pilots were able to exit the main cabin door without injuries as the landing gear did not collapse during the excursion. The aircraft was substantially damaged.