Monthly Archives: January 2012

Root Cause Analysis - Incident Investigation

1960 Plane Collision over NYC killed 134

By ThinkReliability Staff

On December 16, 1960, two planes collided about a mile above Brooklyn, New York.  One plane – United Airlines Flight 826 – was in a holding pattern preparing to descend into Idlewild (now John F. Kennedy International) Airport.  The other plane – TWA Flight 266 – was preparing to descend into LaGuardia.  Since both airports serve New York City, they are in fairly close proximity.  The planes, too, were in close proximity – too close, leading to their collision.  In addition to the 84 passengers killed on the United flight (though one would survive for a day) and the 44 passengers killed on the TWA flight, 6 people were killed in the neighborhood of Park Slope, where the United plane landed.

This incident can be outlined in a Cause Map or visual root cause analysis.  We begin with determining the impacted goals.  First, the 134 total deaths were an impact to the safety goal.  The United flight crash resulted in a fire that affected more than 200 buildings, an impact to both the environmental and property goal.   The liability for the crash was assigned to both airlines and the government, an impact to the customer service goal.  There was another impact to the property goal because both planes were destroyed.  Lastly, the labor goal was impacted due to the rescue efforts of the more than 2,500 personnel who responded to the two crash sites.

These impacts to the goals occurred when both planes crashed after colliding.  The planes collided after their flight paths brought them into too close of proximity.  The United flight was estimated to be 12 miles outside its holding  pattern when the crash occurred, possibly because the ground beacon was not working.  The controllers at Idlewild were unaware of the plane’s position as planes were not tracked in holding patterns as it was too difficult to identify individual planes.  The planes were unaware of each other.  The visibility was extremely poor due to foggy, cloudy, sleety and snowy weather.  The United plane had lost the ability to use their instruments due to a loss of a receiver.  (The cause is unknown.)  Additionally, the controllers at LaGuardia (who were guiding in the TWA flight) were unable to reach the TWA plane to warn them of the close proximity of the United plane.

Although comprehensive details are not known about the crash, much of the information used to put together the investigation was obtained from the flight recorder (or “black box”).  This is now a main source of data in aviation accident investigations.  The evidence in this case was used to divide up liability for the accident very exactly – 61% to United Airlines, 24% to the US government and the remainder to TWA.

To view the Outline and Cause Map, please click “Download PDF” above.

Root Cause Analysis - Incident Investigation

Fatal Cruise Ship Accident

By ThinkReliability Staff

At least 11 people have been killed – with 24 still missing – after the cruise ship Costa Concordia ran aground on rocks near the island of Giglio, Italy.  The ship was taken  manually up to 4 miles off course on a route not  authorized by the company.

This incident can be thoroughly examined in a visual root cause analysis built as a Cause Map.  First, we examine the impacts to the goals for this incident.  The confirmed deaths and missing people are a significant impact to the safety goal.   Additionally, the environmental goal is impacted because of the potential for a spill of the 500,000 gallons of fuel still onboard.  The required evacuation of the ship can be considered a customer impact goal.  The loss of use of the ship – estimated to be $85 to $95 million for lost usage in the next year and the decrease in bookings due to concern over the incident can be considered an impact to the production/schedule goal.  The damage to the ship, which was recently built and insured for approximately $575 million, is an impact to the property goal and the rescue and recovery efforts are an impact to the labor goal.

Once we have these impacts to the goals, we can begin an analysis by asking “why” questions.  The impact to the safety goal – dead and missing passengers and crew – were caused by the ship running aground on rocks and  some issues with the evacuation process.  The ship ran aground on rocks because it got too close to the island in a manually programmed unauthorized deviation of the ship’s route, potentially to provide passengers with a better view.  This deviation in route, sometimes called a “fly by”, had been previously authorized by the company.  No crew members questioned the change in route by the Captain, noting that onboard he is solely responsible for the ship.  (Note that with great power comes great responsibility, and the Captain has been charged with manslaughter.)   Although the ship contains alarms meant to warn the crew when the ship goes off-course, these alarms are deactivated when the ship route is manually altered.

There were some issues with the evacuation of the ship, though as the company notes, not due to the evacuation procedure, which was externally reviewed in November.  Rather the issues were caused by the severe list of the ship (it was leaning almost completely to one side), which affects the ability to use the lifeboats.  Additionally, some of the passengers (who had just come aboard) had not yet completed a lifeboat drill.  The drill is required to be performed within 24 hours of boarding the ship and was scheduled for the morning after departure. The grounding occurred just 3.5 hours after departure.

Currently, rescue and recovery efforts continue.  Attempts are being made to remove fuel from the ship, which is in a protected area.  Concern about cruise ships in the area have previously been raised, with some wanting to limit ships that are allowed in the area.  Additionally, both the cruise ship company and the government are reconsidering the timing of lifeboat drills in order to ensure the best results for passengers in issues like these.

To view the Root Cause Analysis investigation, please click “Download PDF” above

Root Cause Analysis - Incident Investigation

Radioactive Release in the 1960s due to Inadvertent Dropping of Nuclear Weapons

By ThinkReliability Staff

In the history of nuclear weapons in the U.S., two accidents (or inadvertent drops) of nuclear weapons have resulted in widespread dispersal of nuclear materials.  These two incidents occurred two years apart, within a week.  The incidents had many similarities: in both cases, a B-52 bomber carrying nuclear weapons was damaged in air during an airborne alert mission and released nuclear weapons, which released radioactive material over a large area.  In both cases, there were significant impacts to the safety, environmental, customer service, property and labor goals.

Palomares: On January 17, 1966, a B-52 and KC-135 crashed during refueling above Palomares, Spain.  The KC 135 exploded, killing the entire crew of four.   The B-52 broke up mid-air, killing three crew members (four more were able to eject) and releasing four nuclear weapons.  Two of the weapons’ parachutes failed, and the weapons were destroyed, releasing radioactive material causing extensive cleanup of the 1,400 contaminated tons of soil and debris.  (Additionally, one of the intact bombs fell into the ocean and was not recovered for three months.) This was the third refuel of the mission and it’s unclear what exactly went wrong, though due to the close proximity required, mid-air refueling is extremely risky.

Thule: A fire began in a B-52 when flammable cushions were stuffed under a seat, covering the heat duct.  Hot air from the engine manifold was redirected into the cabin in an attempt to warm it up, which ignited the cushions.  The crew of the B-52 was unable to extinguish the fire and the pilot lost instrument visibility.  The generators failed (for reasons that aren’t clear), cutting all engine power.  The crew bailed, the plane crashed, and the two weapons were destroyed along with the plane, again releasing radioactive material that led to a four-month cleanup mission.

The causes of these two incidents have one thing in common – both resulted from planes carrying nuclear weapons as part of an airborne alert mission.  Although many safeguards were taken due to the high risk of the missions, extremely serious impacts still resulted.  Thus the decision was made to cancel airborne alert missions.  When the risk is too high, sometimes the only solution is to end the situation resulting in the risk.

We can look at these two incidents together in a Cause Map, or visual root cause analysis.  To view the Outlines,  Timeline and Cause Maps in a three-page downloadable PDF, please click “Download PDF” above.  Or click here to read more.

Root Cause Analysis - Incident Investigation

Number of Poached Rhinos Hits All Time High

By Kim Smiley

Rhinoceros, commonly called rhinos, have long been hunted for their horns.  Three of the five species of rhinos are considered critically endangered.  According to the National Geographic News Watch, at least 443 rhinos were killed in South Africa in 2011, a significant increase from 333 the previous year.  South Africa is home to more than 20,000 rhinos, which is over 90% of the rhinos in Africa.  For a little perspective on how significantly the problem has grown, South Africa only lost about 15 rhinos a year a decade ago.

Experts in the field have concluded that the number of rhinos lost through unnatural means, both illegal poaching and the less common legal hunts allowed by the government, will result in a decline in the population of rhinos.

This problem can be investigated by building a Cause Map, an intuitive, visual root cause analysis method.  To begin a Cause Map, the impact to the organizational goals is first determined and then “why” questions are asked to add Causes to the map.  In this example, the major organizational goal being considered is the impact to the environmental.  The environmental goal is impacted because the poaching of rhinos hit an all time high.  This happened because of two things, poachers want to hunt rhinos and the methods in place to prevent poaching are ineffective.

Poachers want to hunt rhinos because the black market value of their horns is extremely high.  They are worth more than gold by weight.  Poachers are able to sell the horns for high prices because consumers are both willing and able to pay huge sums.  There is a strong market for rhino horn because of long standing beliefs that rhino horn has medicinal uses, primarily in Asian cultures.  The number of people able to come up with large amounts of money has also increased with the rise of an affluent middle class in many Asian countries.

The poaching is also increasing because it’s very difficult to prevent it.  The rhinos live in a large, wild habitat.  It’s simply difficult and expensive to patrol and defend such a large region.  The poachers are very well armed because they are backed by international crime syndicates with deep pockets.  It’s a huge challenge for the governments involved to prevent the poaching from occurring.

This problem will likely continue to increase until the demand for the rhino horns starts to decrease.  Modern medical research has concluded that rhino horn has no medicinal value, but as long as people are willing to pay big money for them, someone will find a way to meet that demand.

As an interesting aside, theft of rhino horns from museums has also risen dramatically.  At least 30 horns were stolen from museums this past year.  Click here to learn more.