Tag Archives: root cause analysis

Root Cause Analysis - Incident Investigation

New Regulations Aim to Reduce Railroad Crude Oil Spills

By ThinkReliability Staff

The tragic train derailment in Lac-Mégantic, Quebec on July 6, 2013 (see our previous blog on this topic) ushered in new concerns about the transport of crude oil by rail in the US and Canada. Unfortunately, the increased attention has highlighted a growing problem: spills of crude oil transported via rail, which can result in fires, explosions, evacuations, and potentially deaths. (Luckily there have been no fatalities since the Lac-Mégantic derailment.) According to Steve Curwood of Living on Earth, “With pipelines at capacity the boom has lead a 4,000 percent increase in the volume of crude oil that travels by rail, and that brought more accidents and more oil spills in 2014 than over the previous 38 years.”

This follows a period of increases in railroad safety – according to the US Congressional Research Service, “From 1980 to 2012, railroads reduced the number of accidents releasing hazmat product per 100,000 hazmat carloads from 14 to 1.” From October 19, 2013 to May 6, 2015, there were at least 12 railcar derailments that resulted in crude oil spills. (To see the list of events, click on “Download PDF” and go to the second page.)

Says Sarah Feinberg, acting administrator of the Federal Railroad Administration (FRA), “There will not be a silver bullet for solving this problem. This situation calls for an all-of-the-above approach – one that addresses the product itself, the tank car it is being carried in, and the way the train is being operated.” All of these potential risk-reducing solutions are addressed by the final rule released by the FRA on May 1, 2015. (On the same day, the Canadian Ministry of Transport released similar rules.) In order to view how the various requirements covered by the rule impact the risk to the public as a result of crude oil spills from railcars, we can diagram the cause-and-effect relationships that lead to the risk, and include the solutions directly over the cause they control. (To view the Cause Map, or visual root cause analysis, of crude oil train car derailments, click on “Download PDF”.)

The product: Bakken crude oil (as well as bitumen) can be more volatile than other types of crude oil and has been implicated in many of the recent oil fires and explosions. In addition to being more volatile, the composition (and thus volatility) can vary. If a material is not properly sampled and characterized, proper precautions may not be taken. The May 1 rule incorporates a more comprehensive sampling and testing program to ensure the properties of unrefined petroleum-based products are known and provided to the DOT upon request.   (Note that in the May 6, 2015 derailment and fire in Heimdahl, North Dakota, the oil had been treated to reduce its volatility, so this clearly isn’t an end-all answer.)

The tank car: Older tank cars (known as DOT-111s) were involved in the Lac-Mégantic and other 2013 crude oil fires. An upgrade to these cars, known as CPC-1232, hoped to reduce these accidents. However, CPC-1232 cars have been involved in all of the issues since 2013. According to Cynthia Quarterman, former director of the Pipeline and Hazardous Materials Safety Administration, says that the recent accidents involving the newer tank cars “confirm that the CPC-1232 just doesn’t cut it.”

The new FRA rule establishes requirements for any “high-hazard flammable train” (HHFT) transported over the US rail network. A HHFT is a train comprised of 20 or more loaded tank cars of a Class 3 flammable liquid (which includes crude oil and ethanol) in a continuous block or 35 or more loaded tank cars of a Class 3 flammable liquid across the entire train. Tank cars used in HHFTs constructed after October 1, 2015 are required to meet DOT-117 design criteria, and existing cars must be retrofitted based on a risk-based schedule.

The way the train is being operated: The way the train is being operated includes not only the mechanics of operating the train, but also the route the train takes and the notifications required along the way. Because the risk for injuries and fatalities increases as the population density increases, the rule includes requirements to perform an analysis to determine the best route for a train. Notification of affected jurisdictions is also required.

Trains carrying crude oil tend to be very large (sometimes exceeding one mile in length). This can impact stopping distance as well as increase the risk of derailment if sudden stopping is required. To reduce these risks, HHFTs are restricted to 50 mph in all areas, and 40 mph in certain circumstances based on risk (one of the criteria is urban vs. rural areas). HHFTs are also required to have in place a functioning two-way end of train or distributed power braking system. Advanced braking systems are required for trains including 70 or more loaded tank cars containing Class 3 flammable liquids and traveling at speeds greater than 30 mph, though this requirement will be phased in over decades.

It is important to note that this new rule does not address inspections of rails and tank cars. According to a study of derailments from 2001 to 2010, track problems were the most important causes of derailments (with broken rails or track welds accounting for 23% of total cars derailed). A final rule issued January 24, 2014 required railroads to achieve a specified track failure rate and to prioritize remedial action.

To view the May 1 rule regarding updates to crude-by-rail requirements, click here. To view the timeline of incidents and the Cause Map showing the cause-and-effect relationships leading to these incidents, click “Download PDF”.

Root Cause Analysis - Incident Investigation

ISS Supply Mission Fails

By Kim Smiley

An unmanned Progress supply capsule failed to reach the International Space Station (ISS) and is expected to burn up during reentry in the atmosphere along with 3 tons of cargo.  Extra supplies are stored on the ISS and the astronauts onboard are in no immediate danger, but the failure of this supply mission is another in a string of high-profile issues with space technology.

This issue can be analyzed by building a Cause Map, a visual format of root cause analysis.  A Cause Map intuitively lays out the causes that contributed to an issue to show the cause-and-effect relationships.  To build a Cause Map, “why” questions are asked and the answers are documented on the Cause Map along with any relevant evidence to support the cause.

So why did the supply mission fail? The mission failed because the supply capsule was unable to dock with the ISS because mission control was unable to communicate with the spacecraft.  The Progress is an unmanned Russian expendable cargo  capsule that cannot safely dock with a space station without communication with mission control.  Mission control needs to be able to verify that all systems are functional after launch and needs a communication link to navigate the unmanned capsule through docking.

Images of the capsule showed that two of the five antennas failed to unfold leading to the communication issues.  Debris spotted around the capsule while it was in orbit indicates a possible explosion.  No further information has been released about what might have caused the explosion and it may be difficult to decisively determine the cause since the capsule will be destroyed in orbit.

The ISS recycles oxygen and water to an impressive degree and food is the first supply that would run out on the ISS, but NASA has stated that there are at least four months of food onboard at this time.  The failure of this mission may mean that the cargo for future missions will need to be altered to include more basic necessities and less scientific equipment, but astronaut safety is not a concern at this time. The failure of this mission does put additional pressure on the next resupply mission scheduled to be done by SpaceX in June in addition to creating more bad press for space programs that are already struggling during a turbulent time.

To view a intermediate Cause Map of this issue, click on “Download PDF” above.

Root Cause Analysis - Incident Investigation

Earthquake Hits Nepal

By Kim Smiley

As anyone paying any attention to the news knows, a magnitude 7.8 earthquake hit Nepal on April 25, 2015.   The same forces that created the Himalayan Mountains are still at work in the region as the Indo-Australian Plate slowly slides under the Eurasian Plate and experts have long warned about the potential for an earthquake in this location.

At least 4,600 people were killed as a result of the earthquake and the United Nations has stated that 8 million people have been affected.  Many people impacted by the disaster lack adequate water and food and are living in temporary shelters without sanitation facilities.  Beyond the sheer scope of the natural disaster, providing emergency assistance has also been difficult because some of the affected villages are in remote locations that are challenging to access and many roads were damaged by the earthquake.  The long-term economic impacts are also predicted to be large because of the significant damage to infrastructure and the fact that local economies relay heavily on tourism.

A Cause Map, a visual root cause analysis, can be built to help understand this disaster better. A Cause Map lays out the cause-and-effect relationships in an intuitive format by asking “why” questions.  In this tragic example, asking why so many fatalities occurred shows that the majority of deaths were caused by collapsing buildings.  Many buildings in the impacted area were unreinforced masonry structures that couldn’t withstand the force of the earthquake.  These buildings are cheaper and quicker to build than more modern construction that would meet building codes designed to survive an earthquake.

Civil unrest in the region has resulted in rapid urbanization and a large demand for housing as people moved into cities. Rapid and relatively unregulated urbanization in a country with one of the lowest per capita incomes in the world proved to be a deadly combination in a region prone to earthquakes. Historically a major earthquake has struck this region about every 75 years and this one had long been predicted.  Says Susan Hough, a geologist with the U.S. Geological Survey, “It was clearly a disaster in the making that was getting worse faster than anyone was able to make it better. You’re up against a Himalayan-scale problem with Third World resources.”

Every disaster and the emergency response to it should be studied to see if there are any lessons learned that can be used to save lives and minimize damage in the future. There is clearly no “solution” that can prevent an earthquake, but even when dealing with a natural disaster there are ways the impact of a disaster could be mitigated.  The possible solutions may not be cheap or easy, but it is important to remember that it is possible. You can’t stop the earthquake, but you can work to build stronger buildings.

Root Cause Analysis - Incident Investigation

Concrete slab smashes truck killing 3

By Kim Smiley

On April 13, 2015, a large section of a concrete barrier fell from an overpass onto a truck in Bonney Lake, Washington. A couple and their baby were in the vehicle and were all killed instantly. Investigators are working to determine what caused this accident and to determine why the road under the overpass remained open to traffic while construction was being done on the overpass.

A Cause Map, a visual method of root causes analysis, can be built to help understand this accident. More information is still needed to understand the details of the accident, but an initial Cause Map can be created now to capture what is known and it can be easily expanded to include additional information as it becomes available. A Cause Map is created by asking “why” questions and visually laying out the answers to show the cause-and-effect relationships. (Click here to learn more about basics of Cause Mapping.)

In this accident, three people were killed because the vehicle they were riding in was smashed by a large slab of concrete. The vehicle was hit by the concrete slab because it was accidently dropped and the truck was under the overpass at the time it fell because the road was open to traffic. (When two causes are both needed to produce and effect, the causes are listed on vertically on the Cause Map and separated by and “and”.) The road would typically have been closed to traffic while heavy work was performed on the overpass, but the work plan for the construction project did not indicate that any heavy work would be performed on the day of the accident.   At some point the actual work schedule must have deviated from the planned schedule, but no change was made in plan for managing traffic resulting in traffic traveling under the overpass while potentially dangerous construction was performed.

Investigators are still working to understand exactly why the concrete slab fell, but early indication is that temporary metal bracing that was supporting the concrete may have failed due to buckling. The concrete barrier on the overpass were being cut into pieces at the time of the accident so that they could be removed as part of a $1.7 million construction project to improve pedestrian access which included adding sidewalks and lights.

Once the details of what causes this tragic accident are better understood, solutions can be developed and implemented that will help reduce the risk of something like this happening again. To view a high level Cause Map of this accident, click on “Download PDF” above.

You can also read a previous blog “Girder Fell on Car, Killing 3” to learn more about a similar accident that occurred in 2004.

Root Cause Analysis - Incident Investigation

Distraction Related Accidents: Eyes on Road, Hands on Wheel, AND Mind on Task

By  Sarah Wrenn

Admit it – you’ve checked your phone while driving.  We’ve likely all been guilty of it at some point.  And despite knowing that we’re not supposed to do it – it’s against the law in most states and we understand that the distraction increases our risk of having an accident – we still do it.  Why?

On March 31, 2015, the National Transportation Safety Board (NTSB) held its first roundtable discussion on distractions within the transportation industry.  In 2015, the NTSB added “Disconnect from Deadly Distractions” to its “Most Wanted List of Transportation Safety Improvements for 2015.”  This list represents the NTSB’s priorities to increase awareness and support for key issues related to transportation safety.  Other critical topics include “Make Mass Transit Safer” and “Require Medical Fitness for Duty.”

Representatives from all modes of transportation, technology, law enforcement, insurance, researchers, advocates, and educators came together for discussion related to distractions facing vehicle operators.

“New technologies are connecting us as never before – to information, to entertainment, and to each other,” said NTSB Member Robert Sumwalt. “But when those technologies compete for our attention while we’re behind the wheel of a car or at the controls of other vehicles, the results can be deadly.”

Digging into the causes

So let’s take a look at some of the causes related to an accident where the operator is distracted.  In addition to the accident occurring because of the distraction, the level of driver expertise is also a factor.  A large effort has been made to raise awareness and provide education to teenage drivers.  This is in part because, as novice drivers, they have a more limited exposure to driving situations and may not have the ability to react as a more skilled driver.

Operators become distracted

We also want to understand the causes that led to the operator being distracted.  There is a distraction type (or mode) that was introduced, the duration of the distraction, and the individual’s inability to ignore the distraction that result in the operator distraction.  While the type of distraction plays a large role in taking the operator’s eyes off the road, hands off the wheel or mind off the task, the duration of the distraction also is a key factor.  For example, while one’s eyes remain on the road during a phone call, the duration of that call disengages the brain from the task for more time than the act of dialing the phone.  This is not to say that one of these actions is more or less impactful; it is important to note that they both play a role in distracting the individual.

It’s not just the text that is distracting

There are three primary forms of distractions – Visual (taking eyes off of the road), Manual (taking hands off of the wheel), and Cognitive (taking mind off of the task).  Visual and manual types of distractions are very easy to define and generally recognized as risky behaviors while operating a vehicle.  Cognitive distractions are less tangible and therefore more difficult to define.  Research and studies generally define cognitive distractions as when the individual’s attention is divided between two or more tasks.  While technology and activities such as texting or talking on the phone are typically identified as the primary forms of distraction, it is interesting to note that cognitive distractions such as allowing your mind to wander while operating a vehicle can be just as risky.  The AAA Foundation released a 2013 study “Measuring Cognitive Distraction in the Automobile.”  The study rates various tasks such as using a hands-free cell phone and listening to the radio according to the amount of cognitive workload imposed upon an operator.  The study concludes that “while some tasks, like listening to the radio, are not very distracting, others – such as maintaining phone conversations and interacting with speech-to-text systems – place a high cognitive demand on drivers and degrade performance and brain activity necessary for safe driving.”

The forum discussed the concept that ability to multi-task is actually a myth, with evidence and data to conclude that for certain types of activities multi-tasking is not only difficult, but impossible.  For example, tasks such as navigation and speech require the use of the same circuits within the brain.  As such, the brain cannot do both tasks at once.  Instead, the brain is switching between these tasks, resulting in a reduction of focus on the primary task (driving) while attempting to perform a secondary task (speaking).  Therefore, attempting to multi-task introduces a cognitive distraction that increases the risk of unsafe driving.

Just ignore it

Why don’t we just ignore the temptation to become distracted?

Our brains function by releasing serotonin and dopamine when an action occurs that makes us feel good.  Dr. Paul Atchley of the University of Kansas stated: “There is nothing more interesting to the human brain than other people.  I don’t care how you design your vehicle or your roadways, if you have technologies in the vehicle that allow you to be social, your brain will not be able to ignore them.  There are only two things we love, serotonin and dopamine.  The two reward chemicals that come along with all those other things that make us feel good.  There is really nothing more rewarding to us than the opportunity to talk to someone else.”

Surveys performed by various organizations have revealed a large percentage of people (sometimes 3 out of 4) that will admit to being distracted while driving.  Meanwhile, a staggering percent (upwards of 90%) will rationalize the behavior which is a sign of addiction.

Finally, the level of brain development controls our ability to respond to distractions.  For example, a teenager has a less developed fontal cortex than an adult which means, as Dr. David Strayer of the University of Utah explains: “Teens’ frontal cortex, the parts of the brain that do decision-making in terms of multitasking, are underdeveloped.”  Much of the focus on distracted driving is focused on teens and this is justified as their brain development is not yet complete.  It is, however, important to note that this is not just an issue for teens who can’t be separated from their phones or seniors who don’t understand them; this is an issue that crosses all demographics.  Level of brain development is just one factor.

So what can we do?

At the end of the day, we want to identify solutions that are going to effectively reduce the risk of having accidents related to distractions from occurring.  While there will always be some risk, it is key to take a comprehensive approach to education, technology, and policy.  Programs like EndDD.org and stopdistractions.org are focused on bringing awareness, education, and training to youth and adults about the risks of operating vehicles while distracted.  Technology can also be used in a variety of ways to reduce the risk of these types of accidents.  Sensors can be built into vehicles to identify distractions and provide alerts to drivers or apps can be used to disable functions of technology so the receipt of calls and texts are delayed.  Finally, establishing policies and laws that are realistic and enforceable is important so that individuals are held accountable for risky behaviors before an accident occurs.  No one single solution is going to reach everyone and no one single solution is going to eliminate the risk of deadly accidents.  Each one of these solutions has limitations, but they also have advantages.  With a balanced approach to raise awareness and education, provide resources and tools to drivers, and change the culture of what is acceptable while driving, we can reduce the amount of accidents and save lives.

References:

NTSB Roundtable: Disconnect from Deadly Distractions held March 31, 2015, from 9:00 a.m. – 4:00 p.m.

AAA Foundation: Measuring Cognitive Distraction in the Automobile, June 2013

Uncategorized

Crash of Germanwings flight 95252 Leads to Questions

By ThinkReliability Staff

On March 24, 2015, Germanwings flight 9525 crashed into the French Alps, killing all 150 onboard. Evidence available thus far suggests the copilot deliberately locked the pilot out of the cockpit and intentionally crashed the plane. While evidence collection is ongoing, because of the magnitude of this catastrophe, solutions to prevent similar recurrences are already being discussed and, in some cases, implemented.

What is known about the crash can be captured in a Cause Map, or visual form of root cause analysis. Visually diagramming all the cause-and-effect relationships allows the potential for addressing all related causes, leading to a larger number of potential solutions. The analysis begins by capturing the impacted goals in the problem outline. In this case, the loss of 150 lives (everybody aboard the plane) is an impact to the safety goal and of primary concern in the investigation. Also impacted are the property goal due to the loss of the plane, and the recovery and investigation efforts (which are particularly difficult in this case due to the difficult-to-access location of the crash.)

Asking “Why” questions from the impacted goals develops cause-and-effect relationships. In this case, the deaths resulted from the crash of the plane into the mountains of the French Alps. So far, available information appears to support the theory that the copilot deliberately crashed the plane. Audio recordings of the pilot requesting re-entry into the cockpit, the normal breathing of the co-pilot, and the manual increase of speed of the descent while crash warnings sounded all suggest that the crash was deliberate. Questions have been raised about the co-pilot’s fitness for duty. Some have suggested increased psychological testing for pilots, but the agency Airlines for America says that the current system (at least in the US), is working: “All airlines can and do conduct fitness-for-duty testing on pilots if warranted. As evidenced by our safety record, the U.S. airline industry remains the largest and safest aviation system in the world as a result of the ongoing and strong collaboration among airlines, airline employees, manufacturers and government.”

Some think that technology is the answer. The flight voice recorder captured cockpit alarms indicating an impending crash. But these were simply ignored by the co-pilot. If flight guidance software was able to take over for an incapacitated pilot (or one who deliberately ignores these warnings, disasters like this one could be avoided. Former Department of Transportation Inspector General Mary Schiavo says, “This technology, I believe, would have saved the flight. Not only would it have saved this flight and the Germanwings passengers, it would also save lives in situations where it is not a suicidal, homicidal pilot. It has implications literally for safer flight across the industry.”

Others say cockpit procedures should be able to prevent an issue like this. According to aviation lawyers Brian Alexander & Justin Green, in a blog for CNN, “If Germanwings had implemented a procedure to require a second person in the cockpit at all times – a rule that many other airlines followed – he would not have been able to lock the pilot out.”

After 9/11, cockpit doors were reinforced to prevent any forced entry (according to the Federal Aviation Administration, they should be strong enough to withstand a grenade blast). The doors have 3 settings – unlock, normal, and lock. Under normal settings, the cockpit can be unlocked by crewmembers with a code after a delay. But under the lock setting (to be used, for example, to prevent hijackers who have obtained the crew code from entering the cockpit), no codes will allow access. (The lock setting has to be reset every 5 minutes.) Because of the possibility a rogue crewmember could lock out all other crewmembers, US airlines instituted the rule that there must always be two people in the cockpit. (Of course, if only a three-person crew is present, this can cause other issues, such as when a pilot became locked in the bathroom while the only other two flight crew members onboard were locked in the cockpit, nearly resulting in a terror alert. See our previous blog on this issue.)

James Hall, the former chairman of the National Transportation Safety Board, agrees. He says, “The flight deck is capable of accommodating three pilots and there shouldn’t ever be a situation where there is only one person in the cockpit.” In response, many airlines in Europe and Canada, including Germanwings’ parent company Lufthansa, have since instituted a rule requiring at least two people in the cockpit at all times.   Other changes to increase airline safety may be implemented after more details regarding the crash are discovered.

Root Cause Analysis - Incident Investigation

THE WOEFUL TALE OF JACK & JILL

By Jon Bernardi

There has been a disturbing rise of injuries once thought to have been eradicated. Several federal and state agencies are considering legislation to address the very dangerous injuries from the gathering of liquid di-hydrogen oxide from certain unprotected hills and wells. Once upon time became the last straw, when siblings Jack and Jill fetched the ill-fated pail. Not only were crowns injured, but various homeopathic remedies were implemented with little consequence except to other participants, notably Jill.

What caused this unfortunate turn of events?

That question can be answered by building a Cause Map, a visual root cause analysis.  In the Cause Mapping process, the first step is to fill in an Outline with the background information for an issue as well as how the problem impacts the goals.  In this example, the aforementioned fetching impacts quite a number of goals: Safety as crowns were broken; environmental, the spilled di-hydrogen oxide; regulatory, child corporal punishment and child labor laws; customer service, no di-hydrogen oxide available for multiple purposes; production, the delay of supper; and labor, the time needed for medical attention.

Fortunately no property was lost as the well-made bucket survived intact.  Once we have filled out the Outline, the next step is to ask “why” questions to find the different causes that contributed to the problem being analyzed.

So why were they going up a hill? This presents us with a number of potential paths of exploration as to why the well was at the top of a hill. Even without knowing a detailed answer we know that a potential solution would be to get them hooked up an established di-hydrogen oxide system as soon as possible!

Why was there no protection? Broken crowns are a serious affair. This combined with the potential for other injuries from the fractious “tumbling down” incident leaves us to wonder how the well could be constructed in such a manner.

These are areas for further exploration. Even with the unanswered questions we are still able to propose several solutions to ensure that child labor laws are not ignored, hills are properly protected, and home remedies are carefully considered.

To view an Outline and a high level Cause Map for this issue, click on “Download PDF” above.

Uncategorized

March 27, 1977: Two Jets Collide on Runway, Killing 583

By ThinkReliability Staff

March 27, 1977 was a difficult day for the aviation industry.  Just after noon, a bomb exploded at the Las Palmas passenger terminal in the Canary Islands.  Five large passenger planes were diverted to the Tenerife-Norte Los Rodeos Airport, where they completely covered the taxiway of the one-runway regional airport.  Less than five hours later, when the planes were finally given permission to takeoff, two collided on the runway, killing 583, making this the worst accident at the time (and second now only to the September 11, 2001 attacks in the US.)

With the benefit of nearly 40 years of hindsight, it is possible to review the causes of the accident, as well as look at the solutions implemented after this accident, which are still being used in the aviation industry today.  First we look at the impact to the goals as a result of this tragedy.  The deaths of 583 people (out of a total of 644 on both planes) are an impact to the safety goal.  The compensation to families of the victims (paid by the operating company of one of the planes) is an impact to the customer service goal.  The property goal was impacted due to the destruction of both the planes, and the labor goal was impacted by the rescue, response, and investigation costs that resulted from the accident.

Beginning with one of the impacted goals, we can ask why questions to diagram the cause-and-effect relationships related to the incident.  The deaths of the 583 people onboard were due to the runway collision of two planes.  The collision occurred when one plane was taking off on the runway, and the other was taxiing to takeoff position on the same runway (called backtracking).

Backtracking is not common (most airports have separate runways and taxiways), but was necessary in this case because the taxiway was unavailable for taxiing.  The taxiway was blocked by the three other large planes parked at the airport.  A total of five planes were diverted to Tenerife which, having only one runway and a parallel taxiway, was not built to accommodate this number of planes.  There were four turnoffs from the runway to the taxiway; the taxiing plane had been instructed to turn off at the third turn (the first turn that was not blocked by other planes).  For unknown reasons, it did not, and the collision resulted between the third and fourth turnoff.  (Experts disagree on whether the plane would have been able to successfully make the sharp turn at the third turnoff.)

One plane was attempting takeoff, when it ran into the second plane on the runway.  The plane  taking  off was unaware of the presence of the taxiing plane.  There was no ground radar and the airport was under heavy fog cover, so the control tower was relying on positions reported by radio.  At the time the taxiing plane reported its position, the first plane was discussing takeoff plans with the control tower, resulting in interference rendering most of the conversation inaudible.  The pilot of the plane taking off believed he had clearance, due to confusing communication between the plane and the air traffic control tower.  Not only did the flight crews and control tower speak different languages, the word “takeoff” was used during a conversation that was not intended to provide clearance for takeoff.  Based on discussions between the pilot and flight crew on the plane taking off have, investigators believed, but were not able to definitively determine, that other crew members may have questioned the clearance for takeoff, but not to the extent that the pilot asked the control tower for clarification or delayed the takeoff.

After the tragedy, the airport was upgraded to include ground radar.  Solutions that impacted the entire aviation industry included the use of English as the official control language (to be used when communicating between aircraft and control towers) and also prohibited the use of the word “takeoff” unless approving or revoking takeoff clearance.  The potential that action by one of the other crew members could have saved the flights aided in the concept of Crew Resource Management, to ensure that all flight crew members could and would speak up when they had questions related to the safety of the plane.

Though this is by far the runway collision with the greatest impact to human life, runway collisions are still a concern.  In 2011, an Airbus A380 clipped the wing of a Bombardier CRJ (see our previous blog).  Officials at Los Angeles International Airport (LAX) experienced 21 runway incursions in 2007, after which they redesigned the runways and taxiways so that they wouldn’t intersect, and installed radar-equipped warning lights to provide planes with a visual warning of potential collisions (see our previous blog).

To view the outline, Cause Map and recommended solutions from the Tenerife runway collision of 1977, click on “Download PDF” above.  Or, click here to read more.

Root Cause Analysis - Incident Investigation

Houston Ship Channel Closed After Ships Collide

By Kim Smiley

On March 9, 2015, two large ships collided in the Houston Ship Channel, one of the busiest waterways in the United States.  There were no major injuries reported, but the accident resulted in the release of methyl tertiary-butyl ether, commonly called MTBE, a chemical that is used as a fuel additive.  The clean-up and investigation of the collision closed the channel from the afternoon of March 9 until the morning of March 12.

At the time of the collision, the tanker Carla Maersk was traveling outbound in the channel transporting MTBE.  The bulk carrier Conti Perido was heading inbound with a load of steel.  Both ships were significantly damaged by the collision and three cargo tanks ruptured on the Carla Maersk, spilling the MTBE. Limited information has been released about what caused the accident, but a National Transportation Safety Board investigation is underway.  Initial reports are that both vessels were traveling at about 9 knots, which is typical for this stretch so excessive speed does not appear to be a cause.  It has also been reported that it was foggy at the time of the accident which may have played a role in the accident.

An initial Cause Map can be built using the information that is available.  The first step in the Cause Mapping process is to fill in an Outline with the basic background information along with the impacts to the goals.  Like many incidents, this collision impacted several different goals.  The safety goal was impacted because MTBE is toxic and has the potential to cause injuries.  The environmental goal was clearly impacted by the release of MTBE.  The multiple-day closure of the Houston Ship Channel is an impact to the production/schedule goal and the impact to local businesses resulting from closure is an impact to the economic goal.  The damage to the ships is an impact to the equipment goal.

On the outline, there is also a line to record the frequency of how often a similar event has occurred.  It’s important to consider the frequency because a small problem that occurs often may very well warrant a more detailed investigation than a small problem that has only been seen once.  In this example, there have been previous ship collisions.  This accident was the second ship collision to occur in the channel in a week.  Two large ships bumped on March 5, 2015, which did not result in any injuries or pollution.

Release of MTBE is a significant concern, but the impacts of this ship collision could easily have been worse.  MTBE is volatile and flammable so there could have been a fire or the ships could have been carrying something more dangerous.  It may be difficult to get the data, but it would be interesting to know how many near misses have occurred between ships traveling in the channel. The frequency that accidents are occurring needs to be considered along with the details of any individual incident when conducting an investigation. Two collisions in a week is a pretty clear indication that there is potential for more to occur in the future if nothing is changed.

Root Cause Analysis - Incident Investigation

Train Derails in West Virginia

By Kim Smiley

On February 16, 2015, a train hauling 109 tank cars of crude oil derailed in Mount Carbon, West Virginia.  It has been reported that 27 tank cars in the train derailed.  Some of the tank cars were damaged and released an unknown amount of crude oil, resulting in a large fire.  Hundreds of families in the surrounding area were evacuated, but only one injury was reported.

The accident investigation is still ongoing, but what information is known can be used to build an initial Cause Map, a visual format for performing a root cause analysis.  The Cause Map can be easily expanded as needed to document additional information as it becomes available.

The first step in the Cause Mapping process is to fill in an Outline with the basic background information for the issue as well as how the overall goals were impacted. In this example, there were many impacted goals.  The safety goal is impacted because there was an injury, the property goal is impacted because of the damage to the train, the environmental goal is impacted because of the release of oil, etc.  Once the Outline is complete, the Cause Map itself is built by starting with an impact to a goal, asking “why” questions, and laying out all the causes that contributed to an issue.

The significant aftermath of this derailment is known, but little has been released about what specifically caused the train to derail.  It was snowing heavily at the time of the accident, which may have played a role, but since more evidence is needed, a “?” is included on the Cause Map.  Data from the digital data recorder has shown that the train was not speeding at the time of the accident, which has been a factor in previous derailments.  Another fact worth noting is that the damaged train cars were a newer design that incorporated modern safety upgrades.

With so many unknowns, the Federal Railroad Administration is conducting a full-scale investigation to determine exactly what happened.  The damaged tank cars, track, and other components along with relevant maintenance and inspection records will be all be analyzed to better understand this derailment.

Unfortunately, crude oil train accidents are predicted to become increasingly common as the volume of flammable liquids being transported by rail continues to rise.  According to the Association of American Railroad, 40 times more oil was transported by rail in 2012 than in 2008. Hopefully, the lessons learned from this derailment can be used to help reduce the risk of future rail accidents.

To view the Outline and initial Cause Map for this accident, click on “Download PDF” above.