Wendy A. Tadros
Transportation Safety Board of Canada
at the Canadian Aeronautics and Space Institute
Aero Conference 2007
24 April 2007
Good morning and thank you for such a warm welcome. It is indeed my pleasure to speak with you today. As members of the Canadian Aeronautics and Space Institute (CASI), I know that all of you are engaged in the world of aeronautics and many of you actually design aircraft and aeronautical components. And that makes you an important audience for the Transportation Safety Board of Canada.
With me here today is Mr. Mike Mathieu, TSB's Senior Structures Engineer. Mike will be a part of the panel discussion following my remarks and he's also available to speak with you at the break. So, I encourage you to ask him any technical questions you may have.
Admittedly, I am not a scientist, or an engineer for that matter. However, what I do share with everyone here, I am sure, is a fascination with aircraft and flight.
I developed that interest as a child. My father was an air force navigator. And I still remember the first time I watched a jeep disappear whole into the belly of a Hercules. That sight amazed me then. The design that enabled that sight still amazes me to this day.
My fascination with your world explains one of the reasons I chose to become a board member of the Transportation Safety Board, or TSB, and to eventually accept the position as Chair.
The Transportation Safety Board is an independent investigative body with one and only one priority - advancing transportation safety.
Our job is to investigate accidents - whether they occur on the water or in the air, or involve Canada's railways or pipelines - and suggest solutions to improve safety.
When things go wrong, we respond. And that's why our distinctive blue jackets with TSB emblazoned on the back are a common sight at accident scenes.
In the remaining time we have together, I'd like to review some recent accidents and the recommendations we made as a result of our investigations. Further, I'll share my views on a couple of trends we have been keeping a watchful eye on.
Morningstar Air Express Cessna 208
I'll begin with the October 2005 crash of a Morningstar Air Express Cessna 208.
In our investigation, we found that the aircraft took off clean from Winnipeg, Manitoba, just after 5:30 in the morning.
It climbed normally but, within minutes, it began to descend as ice built up on its critical surfaces.
The small plane crashed before it could safely return to the airport.
As a result, the pilot died and the plane was destroyed by the crash and post-impact fire.
Unfortunately, this was not the first accident of its kind. As many of you know, some small aircraft can safely handle icing conditions. On the other hand, the design of others makes them less tolerant, and the Cessna 208 is particularly vulnerable to in-flight icing.
In January 2006, still very early in our investigation, both the TSB and our U.S. counterpart, the National Transportation Safety Board, or NTSB, made recommendations to advance safety for the more than 1500 Cessna 208s that fly worldwide.
This brings to light two other important points.
- First, we don't wait for a final report to take action. When safety issues are urgent, we issue recommendations immediately.
- And, second, our investigations and recommendations often extend beyond our borders to advance the safety of aircraft around the world.
As a result of our Morningstar investigation, the TSB recommended safer procedures for pilots flying Cessna 208s. In response, both the Federal Aviation Administration (FAA) and Transport Canada took immediate action. Cessna 208s encountering moderate in-flight icing must now exit these conditions.
We also addressed the root of the problem by recommending that Transport Canada and the FAA restrict the dispatch of these aircraft into anything more than light icing. We've asked that they prohibit continued operation in these conditions, until it has been demonstrated that they can safely operate in more than light icing.
On dispatch and certification, our challenge is to make a strong and convincing case for change and I can tell you that we don't give up easily.
With Transport Canada, the FAA and the manufacturer, we will continue to focus attention on the airworthiness of Cessna 208s in icing conditions.
Air Transat Airbus A310-300
The second accident I'd like to talk about occurred in March 2005 when an Air Transat Airbus A310-300 series took off from Varadero, Cuba, on its way to Québec, Quebec.
Not long into the flight, the crew and passengers heard a loud noise followed by vibrations. Then, the aircraft started to "Dutch roll." The crew managed to descend, stabilize the aircraft and return safely to Varadero.
Once on the ground, the problem quickly became obvious. The aircraft's rudder had fallen off.
Now, this investigation is still ongoing. But, once again, in keeping with our policy to issue safety recommendations as soon as possible, we issued two that same month-one each to the Canadian and European authorities (recommendations A06-05 and A06-06).
As a result of our Air Transat investigation, we recommended that regulators implement an inspection program to detect rudder damage early. In the United States, the NTSB has taken similar action, reflecting the international importance of the work we do.
These particular recommendations are important for two key reasons.
- First, because of the increasing use of composites in the manufacture of aircraft.
- Second, because while we know a great deal about how metals behave, we still have a lot to learn about how composite materials behave - and about what may cause them to fail and how they fail.
Transport Canada heard us and, along with the National Research Council, is working on inspection techniques for composite materials. Transport Canada also said that it will ask Airbus Industries to review its inspection program for the A310-300 series. This indicates forward movement but we consider this file active and will continue to follow up until an early and consistent detection program is in place for these aircraft.
Since this investigation is continuing, I can't share its conclusions today. However, I can tell you that the scientific work of people like CASI Member Mr. David Zimcik of the National Research Council and TSB's own Mike Mathieu has certainly advanced the world's knowledge of composites. And, proudly, Canadian researchers, designers and others are at the forefront of this new knowledge.
MK Airlines Boeing 747
While the loss of the Air Transat rudder did not cause any injuries, the crew in this next accident were less fortunate. In October 2004, an MK Airlines Limited Boeing 747 took off from Halifax International Airport, Nova Scotia.
The crew was unaware, until it was too late, that insufficient thrust had been used and that the aircraft did not have enough speed to take-off.
The aircraft ran off the end of the runway, became briefly airborne, then struck an earthen berm. The tail section broke away and the aircraft flew about 365 metres before it struck the ground and was consumed by flames.
All seven crew on board were killed in the accident.
Accidents are always due to a number of factors and our investigation determined that the combination at play were:
- a dark take-off environment;
- crew fatigue; and
- inadequate crew training and testing on the software used to calculate take-off performance.
I would like to emphasize this last point.
The crash was not related to the aircraft's design. But the interface between people and technology is adding another dimension to aviation safety. Crews around the world deal with this interface every day whether it is with software components added on to the aircraft or components that were originally part of the design. I would argue that these human performance issues are important elements for designers to consider.
During our investigation, we paid special attention to figuring out why the onboard software generated incorrect information - and what should be done to ensure that this never happens again. Because - based on that faulty information - the aircraft took off using speed and thrust settings that were too low for its weight.
And those settings triggered a sequence of events that destroyed the aircraft and all its cargo and took the lives of seven people.
Understanding the underlying factors - the take-off conditions, the crew fatigue, the inadequate training - enabled us to look beyond the specifics of this accident, to discover unsafe conditions in the system and apply what we learned to advance transportation safety.
There have been a number of similar occurrences around the world, both before and since the MK Airlines crash. The facts in each differ, but the underlying issue is the same. And we concluded that there is a need for further defences.
The theory of "defences in depth" holds that there should be a front-line defence backed up by more and stronger defences behind it.
Based on what we found, we recommended that systems be developed to alert crews of large aircraft when there is not enough power to take off safely. We made this recommendation to the world's regulatory agencies.
Work has already begun to mitigate the risk.
Transport Canada has formed a cross-disciplinary team to research and develop a certified take-off performance monitoring system. We look forward to the contributions of gifted and capable designers as we work to solve the problem of crews taking off without enough power.
MK Airlines is one example of a deadly crash and post-impact fire. One that was clearly not survivable.
We have found that some crashes - particularly with small aircraft - are survivable.
In August 2006, the TSB released its Safety Issues Investigation into post-impact fires.
We conduct Safety Issues Investigations when we note a cluster of accidents with apparent similarities. We examine them in depth to look for a common thread.
In this investigation, we examined post-impact fires in small aircraft. By small, I mean aircraft with a maximum certified take-off weight of 5700 kilograms or 12 566 pounds.
There is a high incidence of small-aircraft crashes and a significant number of these involve post-impact fire. We looked at accidents where the crew or passengers survived the crash but died in the fire that followed.
And we focused our attention on three areas of aircraft design:
- the high volatility of aviation fuel;
- the close proximity of this fuel to the occupants; and
- the limited energy-absorption characteristics of small-aircraft airframes in crash conditions.
Technology and design have been used to reduce death by post-impact fire in the world of race car driving. So, we pondered whether design could be put to the same use in our world.
We made three recommendations to Transport Canada and the Federal Aviation Administration (FAA).
- First, we asked for an updated cost-benefit analysis so regulators could better consider the value of requiring changes to the way small aircraft are built.
- We made two other recommendations aimed at changing aircraft design standards and at taking measures to make existing small aircraft safer.
Transport Canada's response to these recommendations is disappointing. While Transport Canada has acknowledged the risk, it has not committed to mitigate the risks we so clearly identified in our investigation. Discussions will continue. . . .
Bombardier CRJ Flap Failure
The final safety issue I'd like to talk to you about is Bombardier CRJ flap failures.
Our database showed an increasing number of flap failures on CRJ aircraft and a sharp rise in this year. There were 20 reported occurrences in 2005 and 28 in 2006. This January alone, the TSB received 24 reports of CRJ flap failures.
One incident that caught our attention occurred last November in Prince George, British Columbia. An Air Canada Jazz CRJ flight was configured for landing with the flaps set at 45 degrees. While on final approach, the landing conditions became unsuitable and the crew conducted a missed approach.
Rather than coming up when selected, the flaps remained at 45 degrees, placing the aircraft in a high-drag situation. That chapter ended with a diversion to Fort St. John and the aircraft landing with just 500 pounds of fuel remaining.
Although we knew that Transport Canada and Bombardier had been working on this issue for quite some time, the increased frequency and the Prince George event compelled the TSB to take positive action. More needed to be done, and done quickly.
The TSB took action and issued a Board Concern. We told the Minister of Transport that, despite best efforts by the industry and regulators to reduce the number of CRJ flap failures, they were actually increasing.
We asked the Minister of Transport for an action plan - one that will most certainly involve sending designers back to the drawing board!
Well, as the accidents I have described illustrate, when things do go wrong, the TSB responds. Through our investigations and recommendations, we aim to advance transportation safety.
Opportunities for the professional exchange of information - opportunities such as this one today - work in all our favour.
The more you, as designers and engineers, know about the results of our investigations, the more we all benefit from transportation safety.
Let me close then by urging you to keep abreast of our key findings and recommendations. Please consider us an important resource.
For instance, you can download most of our investigation reports as they are made public and you can also subscribe to our ListService to receive the latest information from the Board.
We want to work with you and your members on our one and only priority: to advance transportation safety.
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