Progress report: TSB Canada classifies Resolute Bay Boeing 737 accident as CFIT

In a progress report of their investigation into a fatal Boeing 737 accident at Resolute Bay, the Transportation Safety Board of Canada currently classified the accident as a Controlled Flight Into Terrain (CFIT) occurence.

On 20 August 2011, a First Air Boeing 737-210C aircraft (registration C-GNWN) was being flown as a charter flight from Yellowknife, North West Territories, to Resolute Bay, Nunavut.  At 11:42, during the approach to Runway 35T, First Air Flight 6560 impacted a hill at 396 feet above sea level (asl) and about 1 nautical mile east of the midpoint of the Resolute Bay Airport runway which, itself, is at 215 feet asl. The aircraft was destroyed by impact forces and an ensuing post-crash fire. Eight passengers and the four crew members suffered fatal injuries. Three passengers suffered serious injuries.

The investigators have complete the field phase of the  investigation. With regards to the weather, it was reported that in the hours before the accident, the weather in Resolute Bay was variable with fluctuations in visibility and cloud ceiling. Forty minutes before the accident, the visibility was 10 miles in light drizzle with an overcast ceiling at 700 feet above ground level (agl). A weather observation taken shortly after the accident, reported visibility of 5 miles in light drizzle and mist with an overcast ceiling of 300 feet agl.

The weather conditions required the crew to conduct an instrument approach using the aircraft flight and navigation instruments. The crew planned to conduct an instrument landing system (ILS) approach to Runway 35T. This instrument approach provides guidance down to weather minimums of ¹⁄₂ mile visibility and a ceiling of 200 feet agl.

The crew initiated a go-around 2 seconds before impact. At this time, the flaps were set to position 40, the landing gear was down and locked, the speed was 157 knots and the final landing checklist was complete.

Another aircraft successfully completed an ILS approach to Runway 35T approximately 20 minutes after the accident. NAV CANADA conducted a flight check of the ground based ILS equipment on 22 August 2011; it was reported as serviceable.

The technical examination of the aircraft at the accident site revealed no pre-impactproblems. Analysis of the flight data recorder information and examination of the engines at the site indicate the engines were operating and developing considerable power at the time of the accident. Analysis of the aircraft flight and navigational instruments is ongoing.

More information:

• TSB Progress report A11H0002
• ASN Accident Description

Report: LOT B767 Erroneous instrument indications resulting in airspeed and altitude deviations

TSB Canada published the final report of their investigation into an occurrence involving a LOT Polish Airlines Boeing 767-300, June 2009. Erroneous instrument indications resulted in airspeed and altitude deviations.

The LOT Polish Airlines Boeing 767-300 (registration SP-LPA) operating as LOT 2 departed from Chicago-O’Hare International Airport (ORD) and was destined for Warsaw (WAW), Poland. At 22:03 Eastern Daylight Time, while the aircraft was in level cruise flight in the vicinity of North Bay, Ontario, Canada the captain’s airspeed indicator suddenly increased above the maximum operating speed, and an overspeed warning was triggered. The flight crew reduced thrust to flight idle and initiated a climb. As the aircraft slowed, the overspeed warning stopped. The flight crew maintained the nose-up attitude with the reduced thrust setting but the captain’s indicated airspeed suddenly increased again, causing a second overspeed warning. As the flight crew reacted to the second overspeed warning, a simultaneous activation of the stick shaker occurred. During the incident the aircraft climbed from 33 000 to 35 400 feet above sea level (asl) and then descended to approximately 27 900 feet asl. The crew diverted to the Toronto/Lester B. Pearson International Airport where the aircraft landed safely. There was no damage to the aircraft and none of the 10 crew members and 206 passengers were injured.

Findings as to causes and contributing factors:

1. There was a fault within the phase locked loop (PLL) circuitry of the ADC which resulted in sudden and erroneous airspeed and altitude indications on the captain’s instruments.
2. The readings on the captain’s instruments were not compared to those on the first officer’s or the standby instruments. Consequently, the crew believed the captain’s instruments to be correct and made control inputs that resulted in significant altitude and airspeed deviations.

Findings as to risk:

1. LOT Polish Airlines initial and recurrent flight training syllabus does not include practical training for an overspeed warning event. Consequently, flight crews may respond improperly and exacerbate the situation.
2. Although revision 5 of the Boeing SB 767-34A0332 requires changes to chapters of the FCOM, it does not specify what the changes should be. Therefore some manuals may not be properly amended, thereby increasing the risk of crews being ill-informed of the status of the aircraft they operate.
3. The LOT Polish Airlines FCOM incorrectly states that the IAS DISAGREE and ALT DISAGREE EICAS messages will not be displayed on the occurrence aircraft during an unreliable airspeed incident. This increases the risk of a crew misidentifying a problem.
4. The installation of CVRs with less than 2 hours of recording capacity creates the risk that relevant information will not be available to accident investigators and that significant safety issues may not be identified.
5. During the initial examination and disassembly of the ADC, it was noted that there was a large build-up of dust and dirt inside the unit, which could cause an increase in the internal temperature.

Other finding:
In the hold, with thrust at idle, the flight crew did not monitor the airspeed. In an attempt to maintain altitude, the autopilot increased the angle of attack until the stick shaker activated. During the recovery, the crew allowed the aircraft to climb through the flight’s cleared altitude, resulting in a loss of separation.

More information:

• TSB Report Number A09O0117

TSB critices Transport Canada on slow implementation of safety recommendation

A TSB investiation into a cabin smoke and passenger evacuation incident revealed that Transport Canada had not yet implemented an actual regulatory change after accepting a safety recommendation dated December 2007. The recommendation called for passenger safety briefings to include clear direction to leave all carry-on baggage behind during an evacuation.

On March 23, 2010 an Air Canada Airbus A320-211 (registration C-FTJO), operating as flight AC433, departed Montréal/Pierre Elliot Trudeau International Airport, Québec, for Toronto/Lester B. Pearson International Airport, Ontario, with 98 passengers and 6 crew members on board.
In cruise, 1 of the 3 hydraulic systems failed. The flight continued toward destination where the flight made an uneventful landing. While stopped on the runway awaiting a tow, smoke entered the cabin and an evacuation was ordered. Two crew members and 2 passengers received minor injuries during the evacuation.

The TSB concluded that:

1. A leak from the number 1 yaw damper caused fluid to be ingested into the auxiliary power unit and sent through the air conditioning system, resulting in smoke entering the cabin.
2. When the crew ordered the evacuation as a result of the smoke, several persons received minor injuries while exiting the aircraft via the emergency slides.

It appeared that many passengers deplaned with their carry-on luggage. It could not be determined whether this was due to the fact that they were not aware of the instructions given by the flight attendants and included in the safety card, or if they were aware, but chose to disregard them. Passengers would have been more aware of this restriction if information was included during the pre-takeoff and pre-landing passenger briefings, as per TSB recommendation A07-07.

The few injuries that did occur may have been aggravated by the fact that the slides were wet from the rain, and the resultant speed of the exiting persons was higher than normal. While the baggage did cause some minor injuries and delays at the bottom of the slides, it did not appreciably increase the evacuation time. Were this a higher level of threat or emergency, however, even a slight delay could have resulted in more serious consequences.

Transport Canada agreed with the Board’s recommendation (A07-07) that called for passenger safety briefings to include clear direction to leave all carry-on baggage behind during an evacuation. However, to date, no regulatory change has been implemented. Due to the extensive delay between TC’s acceptance of this recommendation and the implementation of actual regulatory change, identified safety dificiencies continue to persist.

More information:

• TSB Aviation Investigation Report A10O0045

 

Report: Fatal Grumman G-21 crash in Canada due to VFR flight into instrument weather

The Transportation Safety Board of Canada (TSB) issued their final report of the investigation into the cause of a CFIT accident involving a Gruman G-21 amphibious plane in November 2008, citing VFR flight into instrument meteorological conditions (IMC).

At about 10:13 Pacific Standard Time, the amphibious Grumman G-21A (registration C-FPCK), operated by Pacific Coastal Airlines, departed from the water aerodrome at the south terminal of the Vancouver International Airport, British Columbia, with one pilot and seven passengers for a flight to Powell River, British Columbia. Approximately 19 minutes later, the aircraft crashed in dense fog on South Thormanby Island, about halfway between Vancouver and Powell River. Local searchers located a seriously injured passenger on the eastern shoreline of the island at about 14:00. The aircraft was located about 30 minutes later, on a peak near Spyglass Hill, British Columbia. The pilot and the six other passengers were fatally injured, and the aircraft was destroyed by impact and post-crash fire. The emergency locator transmitter was destroyed and did not transmit.

The investigators concluded the following:

Findings as to causes and contributing factors:

1. The pilot likely departed and continued flight in conditions that were below visual flight rules (VFR) weather minima.
2. The pilot continued his VFR flight into instrument meteorological conditions (IMC), and did not recognize his proximity to terrain until seconds before colliding with Thormanby Island, British Columbia.
3. The indication of a marginal weather improvement at Powell River, British Columbia, and incorrect information from Merry Island, British Columbia, may have contributed to the pilot’s conclusion that weather along the route would be sufficient for a low-level flight.

Findings as to risk:

1. The reliance on a single VHF-AM radio for commercial operations, particularly in congested airspace, increases the risk that important information is not received.
2. Flights conducted at low altitude greatly decrease VHF radio reception range, making it difficult to obtain route-related information that could affect safety.
3. The lack of pilot decision making (PDM) training for VFR air taxi operators exposes pilots and passengers to increased risk when faced with adverse weather conditions.
4. Some operators and pilots intentionally skirt VFR weather minima, which increases risk to passengers and pilots travelling on air taxi aircraft in adverse weather conditions.
5. Customers who apply pressure to complete flights despite adverse weather can negatively influence pilot and operator decisions.
6. Incremental growth in Pacific Coastal’s support to Kiewit did not trigger further risk analysis by either company. As a result, pilots and passengers were exposed to increased risks that went undetected.
7. Transport Canada’s guidance on risk assessment does not address incremental growth for air operators. As a result, there is increased risk that operators will not conduct the appropriate risk analysis as their operation grows.
8. Previous discussions between Pacific Coastal and the pilot about his weather decision making were not documented under the company’s safety management system (SMS). If hazards are not documented, a formal risk analysis may not be prompted to define and mitigate the risk.
9. There were no company procedures or decision aids (that is, decision tree, second pilot input, dispatcher co-authority) in place to augment a pilot’s decision to depart.
10. Because the aircraft’s emergency locator transmitter (ELT) failed to operate after the crash, determining that a crash had occurred and locating the aircraft were delayed.
11. On a number of flights, pilots on the Vancouver-Toba Inlet route, British Columbia, departed over maximum gross weight due to incorrectly calculated weight and balances. Risks to pilots and passengers are increased when the aircraft is operating outside approved limits.
12. The over-reliance on global positioning system (GPS) in conditions of low visibility and ceilings presents a significant safety risk to pilots and passengers.

Report: Pilots exceeded A319 tail fin limits during wake turbulence upset recovery

File photo of an Air Canada Airbus A319 (Photo: Harro Ranter)

The Transportation Safety Board of Canada (TSB) today released its final investigation report into the January 10, 2008 encounter with wake turbulence involving the Air Canada Airbus A319 operating as flight AC190.
AC190 was en route from Victoria, BC, to Toronto, ON, with 83 passengers and 5 crew members. At 06:48 local time, a series of jolts were felt in AC190, followed by a series of rolls. The crew declared an emergency and diverted the flight to Calgary International Airport, Alberta, where it landed uneventfully at 07:28. Several passengers and crew members were injured.

TSB investrigators concluded that there was enough separation between the A319 and a preceding Boeing 747-400, flight UA896. But the wake vortices from flight UA896 had not dissipated. The wingtip vortices contained sufficient energy to significantly destabilize the A319 in pitch and roll, which contributed to displacement of persons and objects in the cabin.

During recovery from the upset, pilot rudder and sidestick control inputs resulted in aircraft sideslip and g loadings. These contributed to the displacement of occupants and objects in the cabin, as well as placing lateral accelerations and aerodynamic loads on the vertical stabilizer structure to beyond certified limits.
During the 18-second duration of the event, vertical accelerations reached peak values of +1.57g and -0.77g. Lateral accelerations reached peak values of +0.49g (right) and 0.46g (left) during four oscillations. Some actions to rectify the upset were similar to those that contributed to damage to the vertical stabilizer attachment fittings on flight AA587 in 2001. The Airbus A300 in that event crashed after separation of the vertical stabilizer.

The TSB further notes that annual recurrent A319/A320 pilot training at Air Canada did not consistently include reference to the hazards of pilot rudder pedal reversals during upset recovery at high airspeeds. This increased the likelihood that pilots would make inappropriate rudder pedal inputs during upset recoveries.

The aircraft involved in this event were:

• Air Canada Flight AC190: Airbus A319-114 C-GBHZ
• United Airlines Flight UA896: Boeing 747-422 N104UA

TSB Canada launches watchlist of safety issues

The Transportation Safety Board (TSB) released a “Watchlist” that points to nine critical safety issues troubling Canada’s transportation system. The TSB Watchlist took shape after analysts found troubling patterns in their work.

Three safety issues related to aviation:
Problem: There is ongoing risk that aircraft may collide with vehicles or other aircraft on the ground at Canadian airports.
Solution: Improved procedures and the adoption of enhanced collision warning systems are required at Canada’s airports.

Problem: Fatalities continue to occur when planes collide with land and water while under crew control.
Solution: Wider use of technology is needed to help pilots assess their proximity to terrain.

Problem: Landing accidents and runway overruns continue to occur at Canadian airports.
Solution: In bad weather, pilots need to receive timely information about runway surface conditions.
Airports need to lengthen the safety areas at the end of runways or install other engineered systems and structures to safely stop planes that overrun.

TSB issues report on fatal Grumman Goose crash

The Transportation Safety Board of Canada (TSB) released the final report regarding the fatal accident involving a Grumman Goose seaplane in August 2008.

A Pacific Coastal Airlines Grumman G-21A Goose, registered C-GPCD, crashed near Alice Lake, British Columbia, Canada killing five of the seven occupants.

The flight departed Port Hardy Airport, British Columbia, on a visual flight rules flight to Chamiss Bay, British Columbia. While likely climbing to fly above a cloud-covered ridge and below the overcast ceiling, the aircraft stalled. It struck trees. A post-crash fire ignited. The emergency locator transmitter had been destroyed in the crash and did not transmit.

Investigators concluded that:

Findings as to Causes and Contributing Factors:
1. While likely climbing to fly above a cloud-covered ridge and below the overcast ceiling, the aircraft stalled aerodynamically at a height from which full recovery could not be made before striking the trees.
2. The aircraft broke apart upon impact, and electrical arcing from exposed wires in the presence of spilled fuel caused a fire that consumed most of the aircraft.

Findings as to Risk
1. While the company’s established communications procedures and infrastructure met the regulatory requirements, they were not effective in ascertaining an aircraft’s position and flight progress, which delayed critical search and rescue (SAR) action.
2. The emergency locator transmitter was destroyed in the crash and failed to operate, making it difficult for SAR to find the aircraft. This prolonged the time the injured survivors had to wait for rescue and medical attention.