Figure 11: Aviation occurrences
|Reported incidents (mandatory)||790.00||814.00||677.00||636.00||686.00||738.00|
One indicator of aviation transportation safety in Canada is the aircraft accident rate (Figure 12). According to data provided by TC, the estimate of flying activity for 2014 is 4,433,000 hours. The accident rate in 2014 was 4.6 accidents per 100,000 flying hours, down from the 2013 rate of 5.2. There has been a significant downward trend in the accident rate for Canadian-registered aircraft over the past 10 years.
Figure 12: Canadian-registered aircraft accident rate
A total of 22 aviation investigations were started in 2014‑2015, and 22 investigations were completed.
A total of 22 aviation investigations were started in 2014–2015, and 22 investigations were completed. This represents a decrease in the number of investigations completed compared with the previous year (42). The average duration of completed investigations was 546 days, down from the 2013–2014 average of 639 days but higher than the previous five-year average (513 days).
Table 6: Aviation investigations at a glance
of days to complete
|Safety information letters||2||3||0||2||0||3|
Recommendations and progress
In 2014–2015, the Board reassessed responses to 29 of the recommendations issued since 1990. No new aviation safety recommendations were made this year.
Movement on the TSB’s aviation recommendations remains challenging. In Canada, we continue to see the same causes and contributing factors year after year—causes and contributing factors that directly relate to outstanding TSB recommendations. Despite this overall trend, there has been some success on a limited number of recommendations. The status of three recommendations has changed to Fully Satisfactory.
Of the remaining 26 recommendations, one recommendation remains Unable to Assess since no new information was received from TC; eight have been assessed as Satisfactory Intent; five recommendations have been assessed as Satisfactory in Part; four remain Unsatisfactory; and eight were downgraded to Unsatisfactory due to the slow pace of action on the part of TC and inadequate information received from TC.
Another 40 older recommendations also remain outstanding and will be reassessed once updated information is received from TC.
The delay in reducing risk in the aviation industry is a troubling recurring theme, and the Board continues to press hard for improvement in the uptake of its recommendations.
There were a number of important investigations concluded in 2014–2015, and the launch of a new safety study was announced. A number of these investigations touched on TSB Watchlist issues, and others are relevant to the new study on air taxi operations.
Risk of collision on runways is a TSB Watchlist issue. Airport operations require aircraft and vehicles to move between ramps, taxiways, and runways. Sometimes this movement creates conflicts between aircraft, or between aircraft and vehicles. These conflicts can also happen when aircraft or vehicles mistakenly occupy an active take-off or landing area.
Risk of collisions on runways (A13O0045)
On 11 March 2013, a Sunwing Airlines Inc. maintenance van was left unattended with the engine running and in drive gear near a company aircraft at gate H16 at Toronto’s Lester B. Pearson International Airport. The driverless van began to move from the gate area toward the threshold of Runway 24R. When it reached the centre of the runway threshold, air traffic control (ATC) noticed the van. ATC then instructed Air Canada 178, on final approach for Runway 24R, to pull up and go around. The flight crew did not respond to two calls to go around, and the aircraft flew directly over the van, separated by approximately 35 feet. It landed safely on the runway.
The Greater Toronto Airport Authority has undertaken a number of important steps to ensure that this does not reoccur including maintenance of vehicle beacon lighting; personnel training; and safety management system incident reviews.
Safety issues investigation into air taxi operations
The Board is concerned about the number of serious accidents involving air taxi operations. Consequently, in November 2014, the TSB announced that it would conduct a safety issues investigation into Canadian air taxi operations to understand the risks that persist in this important sector of the aviation industry. The study will engage industry, the regulator, and other stakeholders to gain a full understanding of the issues affecting air taxi operations. The Board may make recommendations to address any systemic deficiencies that are identified.
Undocumented effects on performance and handling and aerodynamic stall of an air taxi aircraft (A13P0278)
Arguably, the most intense air taxi activity is on Canada’s west coast, where operators serve a large number of remote communities and industries. On 24 October 2013, a Cessna C-185E operating as an air taxi crashed on an island as it maneuvered for a landing on water.
The TSB’s investigation found that several modifications made to the aircraft had been approved but that the performance and handling characteristics were not documented. The pilot’s expectation of the aircraft’s performance capabilities may therefore not have been accurate. The investigation also identified a risk to airworthiness of the aircraft if multiple modifications are installed without adequate guidance on how to evaluate and document the effects on aircraft handling and performance. Further, there is an increased risk of stall accidents if advanced stall warning systems, such as angle of attack indicators, are not incorporated on aircraft.
The company has since taken action by emphasizing an awareness of aircraft modifications and their effects on aircraft handling during pilot training. It is also in the process of implementing a G switch on its aircraft tracking system as a back up to the aircraft’s emergency locator transmitter, and installing a disconnect G switch on its aircraft batteries to reduce the risk of a post-crash fire, in response to other issues identified during the investigation.
Operating Eurocopter AS 350 helicopters in winter (A12P0008)
There have been many AS 350 engine power-loss accidents associated with ice/snow/water ingestion over the past 25 years. One such accident involved an RCMP helicopter that landed hard at Cultus Lake, British Columbia, on 17 January 2012. The TSB investigation focused on how design and operational factors played a role in the fatal accident.
The investigation found that the protective engine covers had not been installed when the helicopter was parked during a heavy snowfall, and that the air intake system was not cleaned and dried prior to engine start. After the helicopter was started and running at low power, soft ice built up inside the air intake. During take-off at high power, the ice broke free and was ingested into the engine compressor, which led to a complete engine power loss. This caused the rapid loss of the main rotor speed, an extremely high rate of descent, and impact with terrain, which was not survivable.
Since the accident, Eurocopter, the RCMP, and TC have reminded pilots of the need to ensure the engine air intake system is clean prior to takeoff. However, the investigation concluded that the full range of recommended preventative measures cannot easily be accomplished in field operations, and this presents a risk. Given this risk, TC has undertaken to review the engine inlet design of these helicopters.
In the meantime, more than 500 Eurocopter AS 350 and EC 130 helicopters are being flown by 132 operators in Canada. The investigation found these helicopters are susceptible to ice formation in cold weather operations, and the Board is concerned that in certain conditions, these helicopters may be at increased risk of engine flame-out shortly after takeoff.