Question

Search in the Internet and pick an example of an engineering failure or disaster of some type (i.e. building collapse, bridge collapse, dam collapse,… etc.). Describe it in some detail, and discuss what ethical issues might have been at least partly responsible for the failure. In other words, your answer should includes:

1. What failed.

2. Why it failed.

3. Possible corrective actions (How to make it not fail).

4. Who was at fault, and why

Answer 1

SINKING OF TITANIC SHIP

On April 14, 1912, however, the Titanic sideswiped a massive iceberg and sank in less than three hours. Damaging nearly 300 feet of the ship's hull, the collision allowed water to flood six of her sixteen major watertight compartments.

As water rushed into the starboard side of the ship's bow, the ship began to tilt down in front and slightly to the right. By midnight, water in the damaged compartments began to spill over into others because the compartments were watertight only horizontally and the walls extended only a few feet above waterline.

Causes of the Rapid Sinking
On an expedition in 1991 to the Titanic wreck, scientists discovered a chunk of metal lying on the ocean floor that once was a part of the Titanic's hull. The Frisbee sized piece of steel was an inch thick with three rivet holes, each 1.25 inches in diameter. Since the retrieval of this piece of steel, extensive research has been done to uncover additional clues to the cause of the rapid sinking of the Titanic. The following is a discussion of the material failures and design flaws that contributed to the disaster.

Material Failures
When the Titanic collided with the iceberg, the hull steel and the wrought iron rivets failed because of brittle fracture. A type of catastrophic failure in structural materials, brittle fracture occurs without prior plastic deformation and at extremely high speeds. The causes of brittle fracture include low temperature, high impact loading, and high sulphur content. On the night of the Titanic disaster, each of these three factors was present: The water temperature was below freezing, the Titanic was travelling at a high speed on impact with the iceberg, and the hull steel contained high levels of sulphur.The damage caused by the collision allowed water to flood six of the sixteen major watertight compartments. As water rushed into the starboard side of the ship's bow, the ship began to tilt down in front and slightly to the right. By midnight, water in the damaged compartments began to spill over into others because the compartments were watertight only horizontally and the walls extended only a few feet above waterline.

The Hull Steel :

The first hint that brittle fracture of the hull steel contributed to the Titanic disaster came following the recovery of a piece of the hull steel from the Titanic wreck. After cleaning the piece of steel, the scientists noted the condition of the edges. Jagged and sharp, the edges of the piece of steel appeared almost shattered, like broken china. Also, the metal showed no evidence bending or deformation. Typical high-quality ship steel is more ductile and deforms rather than breaks.

Further evidence of the brittle fracture of the hull steel was found when a cigarette-sized coupon of the steel taken from the Titanic wreck was subjected to a Charpy test. Used to measure the brittleness of a material, the Charpy test is run by holding the coupon against a steel backing and striking the coupon with a 67 pound pendulum on a 2.5-foot-long arm. The pendulum's point of contact is instrumented, with a readout of forces electronically recorded in millisecond detail. A piece of modern high-quality steel was tested along with the coupon from the hull steel. Both coupons were placed in a bath of alcohol at -1°C to simulate the conditions on the night of the Titanic disaster. When the coupon of the modern steel was tested, the pendulum swung down and halted with a thud; the test piece had bent into a "V." However, when the coupon of the Titanic steel was tested, the pendulum struck the coupon with a sharp "ping," barely slowed, and continued up on its swing; the sample, broken into two pieces, sailed across the room.
A microstructural analysis of the Titanic steel also showed the plausibility of brittle fracture of the hull steel. The test showed high levels of both oxygen and sulphur, which implies that the steel was semi-kilned low carbon steel, made using the open-hearth process. High oxygen content leads to an increased ductile-to-brittle transition temperature, which was determined as 25 to 35°C for the Titanic steel. Most modern steels would need to be chilled below -60°C before they exhibited similar behavior. High sulphur content increases the brittleness of steel by disrupting the grain structure The sulphur combines with magnesium in the steel to form stringers of magnesium sulphide, which act as "highways" for crack propagation. Although most of the steel used for shipbuilding in the early 1900s had a relatively high sulphur content, the Titanic's steel was high even for the times.

The Rivets :

The wrought iron rivets that fastened the hull plates to the Titanic's main structure also failed because of brittle fracture from the high impact loading of the collision with the iceberg and the low temperature water on the night of the disaster.As the iceberg scraped along sections of the Titanic's hull, the rivets were sheared off, which opened up riveted seams. Also, because of the tremendous forces created on impact with the iceberg, the rivet heads in the areas of contact were simply popped off, which caused more seams to open up. Normally, the rivets would have deformed before failing because of their ductility, but with water temperatures below freezing, the rivets had become extremely brittle.
When the iceberg tore through the hull plates, huge holes were created that allowed water to flood the hull of the ship. As a result, rivets not in the area of contact with the iceberg were also subjected to incredible forces. Like a giant lever, the hull plates transferred the inward forces, applied to the edges of the cracked plates by the water rushing into the hull, to the rivets along the plate seams. The rivets were then either elongated or snapped in two, which broke the caulking along the seams and provided another inlet for water to flood the ship.

Design Flaws
Along with the material failures, poor design of the watertight compartments in the Titanic's lower section was a factor in the disaster. The lower section of the Titanic was divided into sixteen major watertight compartments that could easily be sealed off if part of the hull was punctured and leaking water. Sealing off the compartments was completed immediately after the damage was realized, but as the bow of the ship began to pitch forward from the weight of the water in that area of the ship, the water in some of the compartments began to spill over into adjacent compartments. Although the compartments were called watertight, they were actually only watertight horizontally; their tops were open and the walls extended only a few feet above the waterline. If the transverse bulkheads (the walls of the watertight compartments that are positioned across the width of the ship) had been a few feet taller, the water would have been better contained within the damaged compartments. Consequently, the sinking would have been slowed, possibly allowing enough time for nearby ships to help. However, because of the extensive flooding of the bow compartments and the subsequent flooding of the entire ship, the Titanic was gradually pulled below the waterline.

Safety Regulations
Along with the changes in ship design that resulted from the Titanic disaster, safety regulations were established to govern passenger ships while at sea. Many of these regulations were established at the 1948 Convention on Safety of Life at Sea.

The mandatory use of the wireless, the increased lifeboat capacity, and the implementation of the ice patrol-each of these was developed to prevent accidents similar to the sinking of the Titanic. Wireless is the means of communication for ships at sea. The regulations require that ships exceeding 1600 tons be equipped with wireless apparatus. Use of the wireless is beneficial for ships because they are able to receive weather reports, check their positions, and call for help in emergencies. On the night of the Titanic disaster, several warnings were called in to the Titanic from ships aware of her position. Following her collision with the iceberg, the Titanic was able to send out distress signals to other ships with her position and the status of her damage so help was on the way immediately.

Although there was room on deck for twice as many lifeboats, the Titanic carried lifeboats for just over half of the passengers and crew on board. The designer of the Titanic had allowed room on deck for two rows of lifeboats, but one row was removed before the voyage began to make the deck more aesthetically pleasing. With outdated British Board of Trade regulations, the Titanic's twenty lifeboats actually exceeded requirements by 10 percent capacity.The new safety regulations increased the required number of lifeboats to a number that would accommodate all passengers and crew aboard the ship. Based on the length of the ship, a given number of davits, which are the mechanism used to raise and lower the lifeboats, are mounted along the perimeter of the lower deck. If the minimum lifeboat capacity is not met, additional lifeboats must be stowed under other boats. Regulations also specify that each of the lifeboats must carry oars, sails, a compass, signalling devices, food, and water. In addition, for large ships, two of the boats need to be motor boats.

The United States Government began the ice patrol so that ships travelling between England and the United States could be alerted of approaching ice fields. The ice patrol studies and observes the ice conditions in the North Atlantic in order to keep track of where the ice fields are in relation to nearby ships. Ice fields, large expanses of floating ice that are more than five miles in their greatest dimension, shift around depending on weather conditions. Therefore, without the ice patrol, ships would need to constantly monitor the positions of the ice fields. For the Titanic, the ice patrol could have informed the captain of the ice fields and surrounding icebergs and instructed him to stop the ship until morning.