Tag Archives: bus

Root Cause Analysis - Incident Investigation

5 killed and dozens injured when duck tour boat collides with bus

By Kim Smiley

Five people were killed and dozens more injured when an amphibious Ride the Ducks tour boat collided with a charter bus in Seattle on September 24, 2015.  The circumstances of the accident were particularly unfortunate because two large vehicles carrying tour groups across a busy bridge were involved.  Traffic was mangled for hours as emergency responders worked to treat the high number of victims, investigate the accident and clear the roadway.

The National Transportation Safety Board (NTSB) is investigating the accident to determine exactly what led to the collision and if there are lessons learned that could help reduce the risk of a similar crash in the future.  Potential issues with the duck boat are some of the early focuses of the investigation.  In case you are unfamiliar, duck boats are amphibious landing craft that were used by the U.S. Army during World War II that have been refurbished for use as tour vehicles that can travel on both water and land to give visitors a unique way to experience a city.  Their military designation DUKW was changed to the more user-friendly duck boat moniker that is used by many tour companies throughout the world.

Eyewitnesses of the accident have reported that the duck boat unexpectedly swerved while crossing the bridge, slamming into the driver’s side of the tour bus.  Reports are that the left front wheel of the duck boat locked up and the driver lost control of the vehicle.  NTSB investigators have stated that the duck boat didn’t have a recommended axle repair done that was recommended in 2013 and that they are working to determine whether or not this played a role in the accident.

Investigators are also looking into whether or not Seattle Ride the Ducks was notified of the repair.  Photos of the wrecked duck boat show that the front axle sheared and the left wheel popped off the vehicle, but it hasn’t been conclusively determined whether the damage was the cause of the accident or occurred during the accident.  The issues with the axle certainly seem like a smoking gun, but a thorough investigation still needs to be performed and the process will take up to a year.  If there was a mechanical failure on the duck boat unrelated to the already identified axle issue, that will need to be identified and reviewed to see if it applies to other duck tour vehicles.

This severity of this accident is raising concerns about the overall safety of duck tours.  The duck boat involved in this accident underwent regular annual inspections and was found to meet federal standards.  If a mechanical failure was in fact involved, hard questions about the adequacy of standards and inspections will need to be asked.  The issue of the recommended repair that was not done also raises questions about how the recommendations are passed along to companies running duck boat tours as well as incorporated into inspection standards.

Click on “Download PDF” above to see an outline and Cause Map of this issue.

Root Cause Analysis - Incident Investigation

Why Don’t All School Buses Have Seat Belts?

By Kim Smiley

Nearly every state in the US has a law requiring seat belts to be worn in cars. The lone state that doesn’t require adults to wear seat belts, New Hampshire, still has a law requiring children under 18 to wear seat belts.

Currently, only 6 states require seat belt in school buses.  The federal government does not require seat belts to be in installed in buses weighing over 10,000 lbs.  The regular school buses that make up 80 percent of the buses in this country exceed this weight limit and most do not have seat belts.

So if seat belts are required by law in cars, why don’t all school buses have seat belts?

Like most engineering problems, this isn’t as simple a question as it first appears.  The main reason that seat belts aren’t required on all buses is that buses are fundamentally different from cars.

School buses are heavier and taller than cars.  During an accident, a passenger on a bus experiences less severe crash forces than an occupant of a passenger car.  The interior of a modern school bus is designed to protect passengers passively through something called compartmentalization.  The seats are strong, closely-spaced, high backed, and covered in 4 inch thick foam to absorb energy.  The passenger is protected by the cushioned compartment created by the seats.

Buses are considered to be the safest form of ground transportation.  According to the National Highway Traffic Safety Administration, buses are approximately seven times safer than passenger cars or light trucks.

But would seat belts make them even safer?

This is subject to debate.  There are groups pushing for the federal government to require seat belts on all buses.  Others believe that the potential for misuse and incorrectly worn seat belts would actually result in a higher risk to safety if seat belts were installed.  There are also practical considerations like finding funding in cash strapped budgets to install seat belts and to buy the extra buses that would be necessary since fewer students can be accommodated on a bus with seat belts than one without.

There are few topics touchier than the safety of children and no clear cut answers to the question of what constitute a design that is safe enough.  It could be useful when dealing with a problem like this where emotions might run high to document all information in a Cause Map.  A Cause Map is a visual root cause analysis that incorporates the information associated with an issue in an easy to read format.  All pertinent evidence and facts associated with the topic can be recorded.  Having the same facts available to all invested parties can help keep the discussion production and uncover the best solutions.

To learn more about school bus safety, please visit the National Transportation Safety Board website and National Highway Traffic Safety Administration website.