case study for engineering problem

8/13/2019 case study for engineering problem

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COLLEGE OF ENGINEERING

DEPARTMENT OF COMMON ENGINEERING

COEB 422 ENGINEERS IN

SOCIETY REPORT

GROUP PROJECT:

QUESTION 1

SHOULD A COMPANY REVEAL/REPLACE

DEFECTIVE PRODUCTS EVEN IF CUSTOMERS

WONT RECOGNIZES THEDEFECTS?

LECTURERS NAME:Assoc. Prof. Dr.NORASHIDAH BTE MD. DIN

SECTION:02

GROUP MEMBER:MOHD AFIQ AFIFE B. ABAS (CE085310)

JOSHUA SIGAR ATING (CE087017)

AHMAD TARMIZI B SHAHANOM (EP085428)

NADIRA BT. MOHD FAUZI (EE085989)

MUHAMMAD AQIF BIN ISMAIL (EE084975)

MUHAMMAD FIRDAUS BIN BADARUDDIN (EE086335)

MUHAMAD SAFIG BIN AMIR HAMZAH (ME086165)

MUHAMAD FAIZ BIN JUHARI (CE085313)


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INDEX

NO. TITLE PAGE NO.

1 INTRODUCTION. 2

2 ETHICAL ACTIONS THAT SHOULD BE CARRIED OUT 3-6

3 Engineer Responsibilities

Before The Product Being Sold

When The Flaw Becomes Apparent

Product After Being Sold

7-17

4 Surveys

Surveys form Graph

Analysis

18-21

5 Case Studies

Case study 1:

Toyota Products Failure

Case study 2:

The Space shuttle Challenger Accident

Case study 3:

Common Incident: Furniture

Case study 3:

Common Incident: Food Products

22-33

6 CONCLUSION. 34

7 REFERENCES. 35

8 APPENDIX 36


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INTRODUCTION

Engineering is an important and learned profession. As an engineer, they are expected to exhibit

the highest standards of honesty and integrity. Engineering has a direct and vital impact on the quality of

life for all people. Accordingly, the services provided by engineers require honesty, impartiality,

fairness, and equity, and must be dedicated to the protection of the public health, safety, and welfare.

Engineers must perform under a standard of professional behaviour that requires adherence to the

highest principles of ethical conduct.

There are several duties that shall be fulfilled by engineer. The first duty is to hold paramount

safety, health and welfare of the public. Besides that, they have to perform services only in areas of their

competence and issue a public statement only in an objective and truthful manner. The most important is

they have to avoid deceptive acts and conduct themselves honourably, responsibly, ethically and

lawfully to enhance the honour reputation and usefulness of the profession.

In this project, we need to discuss whether a company shou ld reveal/ replace defective products

even if customers wont recognise the defect. Based on the Code of Ethics of Engineers, they should

avoid all conduct or practice that deceives the public. Besides that, they should also avoid the use of

statements containing a material misrepresentation of fact or omitting a material fact or omitting a

material fact.

Furthermore, an engineer shall be guided in all their relations by the highest standards of honesty

and integrity. They shall acknowledge their errors and shall not distort or alter the facts. On top of that,

they shall advise their clients or employers when they believe a project will not be successful.

So it is safe to say that a company should reveal or replace the defective products even if

customers wont recognize it. An engineer should be responsible in finding product that has defects

before the product being sold and after the product being sold.


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ETHICAL ACTIONS THAT

SHOULD BE CARRIED OUT

Business ethics are the principles of conduct by which a company operates. This includes how

the company owners want to manage the business and how the owners expect the employees to conduct

themselves. Actions that result in civil lawsuits, criminal liability, or that simply damage the reputation

of a business can all be considered examples of bad business ethics.

Another dilemma the company will experience is when they encountered any products defect

when the products have already in the marketplace. This kind of problem really leaves bad impact

and remarks on the good name of the company. But the question is what should the company take

into consideration when this kind of dilemma occurs? What steps and actions they should take?

And the most important thing is on what are the ethical actions that need to be carried out by a

company that faces with this dilemma? Above all, the main point highlighted here was the ethical

actions that need to be carried out especially by the engineers to encounter this problem.

When we talk about product defects and the engineers responsibilities, the first thing that pop-out in

customers, company and everyone minds for sure converging to the design engineers. Design engineers

takes great responsibilities when this kind of this dilemma occurs. The following are examples of where

a design engineer might be concerned with legal and ethical issues:

Preparing a contract to secure the services of a product data management firm.

Reviewing a contract to determine whether a contractor who built an automated production

facility has satisfactorily fulfilled the terms of a contract. Deciding whether it is legal and ethical to reverse engineer a product.

Managing a design project to avoid the possibility of a product liability suit.

Protecting the intellectual property created as part of a new product development activity.

Deciding whether to take a job with a direct competitor that is bidding on a contract in the area

where you are now working.


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We start by making a distinction between morality and professional ethics. Moral ity refers to those

standards of conduct that apply to all individuals within society rather than only to members of a

special group.These are the standards that every rational person wants every other person to follow and

include standards such as the following:

Respect the rights of others.

Show fairness in your dealings with others.

Be honest in all actions.

Keep promises and contracts.

Consider the welfare of others.

Show compassion to others.

Note that each of these standards of conduct is based on the italicized values. By professional ethics

we mean those standards of conduct that every member of a profession expects every other member to

follow. These ethical standards apply to members of that group simply because they are members of that

professional group. Like morality, standards of ethical conduct are value-based. Some values that are

pertinent to professional ethics include:

Honesty and truth

Honorshowing respect, integrity and reputation for achievement Knowledgegained through education and experience

Efficiencyproducing effectively with minimum of unnecessary effort

Diligencepersistent effort

Loyaltyallegiance to employers goals

Confidentialitydependable in safeguarding information

Protecting public safety and health


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PRODUCT LIABILITY

Another ethical action that should be taken was the most important actions that called as product

liability. Product l iabi li ty refers to the legal actions by which an injured party seeks to recover

damages for personal in ju ry or property loss fr om the producer or sell er of a product.Product liability

suits are pursued under the laws of consumers.

Court decisions on product liability coupled with consumer safety legislation have placed greater

responsibility for product safety on the designer. The following ethical actions of the design process

should be emphasized to minimize potential problems from product liability.

The ethical actions are;

Take every precaution to assure that there is strict adherence to industry and government

standards. Conformance to standards does not relieve or protect the manufacturer from liability,

but it certainly lessens the possibility of product defects.

All products should be thoroughly tested before being released for sale. An attempt should be

made to identify the possible ways a product can become unsafe and tests should be devised to

evaluate those aspects of the design.

When failure modes are discovered, the design should be modified to remove the potential cause

of failure.

The finest quality-control techniques available will not absolve the manufacturer of a product

liability if, in fact, the product being marketed is defective. However, the strong emphasis on

product liability has placed renewed emphasis on quality engineering as a way to limit the

incidence of product liability.

Make a careful study of the relationships between your product and upstream and downstream

components. You are required to know how malfunctions upstream and downstream of your


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product may cause failure to your product. You should warn users of any hazards of foreseeable

misuses based on these system relationships.

Documentation of the design, testing, and quality activities can be very important. If there is a

product recall, it is necessary to be able to pinpoint products by serial or lot number. If there is a

product liability suit, the existence of good, complete records will help establish an atmosphere

of competent behavior.

Documentation is the single most important factor in winning or losing a product liability

lawsuit. The design of warning labels and user instruction manuals should be an integral part of

the design process. The appropriate symbols, color, and size and the precise wording of the label

must be developed after joint meetings of the engineering, legal, marketing, and manufacturing

staffs. Use international warning symbols.

Create a means of incorporating legal developments in product liability into the design decision

process. It is particularly important to get legal advice from the product liability angle on

innovative and unfamiliar designs.

There should be a formal design review before the product is released for production.


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Engineer Responsibilities

1) Before The Product Being Sold

In addition to adaptations related to cultural and consumer preference, the exporter should be aware

that even fundamental aspects of its products may require changing. For example, electrical standards in

many foreign countries differ from U.S. electrical standards. It is not unusual to find phases, cycles, or

voltages (for both residential and commercial use) that would damage or impair the operating efficiency

of equipment designed for use in the United States. These electrical standards sometimes vary even in

the same country. Knowing this requirement, the manufacturer can determine whether a special motor

must be substituted or arrange for a different drive ratio to achieve the desired operating revolutions per

minute.

Similarly, many kinds of equipment must be engineered in the metric system for integration with

other pieces of equipment or for compliance with the standards of a given country. The United States is

virtually alone in its adherence to a non-metric system, and U.S. firms that compete successfully in the

global market realize that conversion to metric measurement is an important detail in selling to overseas

customers. Even instruction or maintenance manuals should take care to give dimensions in centimeters,

weights in grams or kilos, temperatures in Celsius degrees and etc.

Branding, Labelling, and Packaging

Consumers are concerned with both the product itself and the product's supplementary features, such

as packaging, warranties, and service. Branding and labelling products in foreign markets raise new

considerationsfor the U.S. Company such as:

Are international brand names important to promote and distinguish a product? Conversely,

should local brands or private labels be employed to heighten local interest?


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Are the colours used on labels and packages offensive or attractive to the foreign buyer? For

example, in some countries certain colours are associated with death.

Can labels be produced in official or customary languages if required by law or practice?

Does information on product content and country of origin have to be provided?

Are weights and measures stated in the local unit?

Must each item be labelled individually?

Are local tastes and knowledge considered? A dry cereal box picturing a U.S. athlete may not be

as attractive to overseas consumers as the picture of a local sports hero.

Engineers look down on adver tising and adver tising people, for the most part.

Engineers have a low opinion of advertising - and of people whose job it is to create advertising.

The lesson for the business-to-business marketer? Make your advertising and direct mail

informational and professional, not gimmicky or promotional. Avoid writing that sounds like "ad

copy." Dont use slick graphics that immediately identify abrochure or spec sheet as

"advertising." The engineer will be quick to reject such material as "fluff."

Engineers want to believe they are not influenced by ad copy - and that they make their decisions

based on technical facts that are beyond a copywriters understanding. Let them believe it - as

long as they respond to our ads and buy our products.

Engineers do not like a " consumer approach."

There is a raging debate about whether engineers respond better to a straight technical approach, clever

consumer-style ads or something in between. Those who prefer the creative approach argue, "The

engineer is a human being first and an engineer second. He will respond to creativity and cleverness just

like everyone else."

Unfortunately, there is much evidence to the contrary. In many tests of ads and direct mailings, I

have seen straightforward, low-key, professional approaches equal or out pull "glitzy" ads and

mailings repeatedly. One of my clients tested two letters offering a financial book aimed at

engineers. A straightforward, benefit-oriented letter clearly out pulled a "bells-and-whistles"

creative package. And I see this result repeated time and time again.


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Engineers respond well to communications that address them as knowledgeable technical

professionals in search of solutions to engineering problems. Hard-sell frequently falls on deaf

ears here - especially if not backed by facts.

The engineers purchase decision is more logical than emotional.

Most books and articles on advertising stress that successful copy appeal to emotions first, reason

second.

But with the engineering audience, it is often the opposite. The buying decision is what we call a

"considered purchase" rather than an impulse buys. That is, the buyer carefully weighs the facts,

makes comparisons and buys based on what product best fulfills his requirement.

Certainly, there are emotional components to the engineers buying decision. For instance,

preference for one vendor over another is often based more on gut feeling that actual fact. But for

the most part, an engineer buying a new piece of equipment will analyze the features and

technical specifications in much greater depth than a consumer buying a stereo, VCR, CD player

or other sophisticated electronic device.

Copy aimed at engineers cannot be superficial. Clarity is essential. Do not disguise the nature of

what you are selling in an effort to "tease" the reader into your copy, as you might do with a

consumer mail order offer. Instead, make it immediately clear what you are offering and how it

meets the engineers needs.

Engineers want to know the features and specif ications, not j ust the benefi ts.

In consumer advertising classes, we are taught that benefits are everything, and that features are

unimportant. But engineers need to know the features of your product - performance characteristics,

efficiency ratings, power requirements and technical specifications - in order to make an intelligent

buying decision.

Features should especially be emphasized when selling to OEMs (original equipment

manufacturers), VARs (value-added resellers), systems integrators and others who purchase your

product with an intention to incorporate it into their own product.

Example: An engineer buying semiconductors to use in a device he is building doesnt need to be

sold on the benefits of semiconductors. He already knows the benefits and is primarily concerned


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about whetheryoursemiconductor can provide the necessary performance and reliability while

meeting his specifications in terms of voltage, current, resistance and so forth.

Engineers are not turned off by jargon - in f act, they like it.

Consultants teaching business writing seminars tell us to avoid jargon because it interferes with clear

communication.

This certainly is true when trying to communicate technical concepts to lay audiences such as the

general public or top management. But jargon can actually enhance communication when

appealing to engineers, computer specialists and other technical audiences.

Why is jargon effective? Because it shows the reader thatyou speak hislanguage. When you

write direct response copy, you want the reader to get the impression youre like him, dont you?

And doesnt speaking his language accomplish that?

Actually, engineers are not unique in having their "secret language" for professional

communication. People in all fields publicly denounce jargon but privately love it. For instance,

who aside from direct marketers has any idea of what a "nixie" is? And why use that term, except

to make our work seem special and important?

Engineers have their own visual language.

What are the visual devices through which engineers communicate? Charts, graphs, tables, diagrams,

blueprints, engineering drawings, and mathematical symbols and equations.

You should use these visual devices when writing to engineers - for two reasons. First, engineers

are comfortable with them and understand them. Second, these visuals immediately say to the

engineer, "This is solid technical information, not promotional fluff."

The best visuals are those specific to the engineers specialty. Electrical engineers like circuit

diagrams. Computer programmers feel comfortable looking at flow charts. Systems analysts use

structured diagrams. Learn the visual language of your target audience and have your artist use

these symbols and artwork throughout your ad, brochure or mailer.


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Installation

Another element of product preparation that a company should consider is the ease of installing

that product overseas. If technicians or engineers are needed overseas to assist in installation, the

company should minimize their time in the field if possible. To do so, the company may wish to

preassemble or pretest the product before shipping.

Disassembling the product for shipment and reassembling abroad may be considered by the

company. This method can save the firm shipping costs, but it may add to delay in payment if the sale is

contingent on an assembled product. The company should be careful to provide all product information,

such as training manuals, installation instructions, and parts lists - all in the local language - even

relatively simple instructions.

As a side note, because freight charges are usually assessed by weight or volume (whichever

provides the greater revenue for the carrier), a company should give some consideration to shipping an

item unassembled to reduce delivery costs. Shipping unassembled goods also facilitates movement on

narrow roads or through doorways and elevators.


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Engineers Responsibilities

2) When The Flaw Becomes Apparent

What count as the defective products?

Any product with a flaw of some kind can be considered defective. But the law recognizes three ways in

which you may claim

A product is defective:

1. Design defects are problems included in the plan for making the product.A product is

defective by design if, when the designers or engineers made the original plan for the product,

they includedsome flaw that they should have known would lead to injuries.

2. Manufacturing defects are introduced during the making of the product. The design may besafe and free of flaws, but sometime in the process of manufacturing or producing the product,

theproduct picked up a new problem.

3. Fail ur e to warn is a defect in the way manufacturers instructs you to use the product. If the

product could reasonably be dangerous when used correctly, the manufacturer has a

responsibility to tell you about that danger. For example, if an over-the-counter cold medicine

could make you too sleepy to drive safely, the packaging must tell you so. If it does not, the

manufacturer is legally liable for any injuries that result.


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Engineers ethical obligations based on NSPE Code of ethics:

Engineers, in the fulfillment of their professional duties, shall conduct themselves honourably,

responsibly, ethically, and lawfully so as to enhance the honour, reputation, and usefulness of the

profession.

Engineers shall act for each employer or client as faithful agents or trustees.

Engineers shall be objective and truthful in professional reports, statements, or testimony. They

shall include all relevant and pertinent information in such reports, statements, or testimony,

which should bear the date indicating when it was current.

Engineers shall approve only those engineering documents that are in conformity with applicable

standards.


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Engineers Responsibilities

3) Product After Being Sold

Parties Responsible for a Defective Product after being sold.

Anyone linked to the distribution of a product can be perceived as the responsible party. This

includes manufacturers, wholesalers, retail outlets, and even someone in charge of assembling or installing the

product. For strict liability to apply, the exchange of a product must occur somewhere in the professional supply

chain. For example, someone who sells a product on the secondary market (e.g., garage sale) cannot be heldaccountable for product liability.

Defendants in Product Liability Cases

Generally, the claimant in a product liability case should identify all parties in the

product's chain of distribution that may have caused their injuries. The following outlines the

parties involved in the chain of distribution that may be liable for a defective or faulty product. In

some cases, there may be more than one potential defendant in each category.

a) Manufacturer (engineer)

Manufacturing takes place at the beginning of a product's chain of distribution.

The manufacturer of a faulty product may range from a large, multinational corporation

to a person working out of a garage.

When a defective product is part of a larger item, the injured consumer may have

a claim against both the manufacturer of the faulty part and the maker of the product

itself. For instance, if a consumer was injured in a motor vehicle containing an exploding

battery, they could potentially file a claim against the automaker and the battery

manufacturer.

When identifying a defendant in a product liability case, it's important to include

additional parties involved in the design, manufacturing or marketing of a product who


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may be associated with the defect. For instance, product liability claims stemming from a

manufacturing defect may cite quality control engineers as a liable party. Similarly, a

lawsuit may name a design consultant as the defendant if a faulty product resulted from a

design defect. Product liability claims involving a failure to warn may name technical

experts who wrote instructions or warning labels for the product.

b) Retailer

Although retailers are typically not involved in the manufacturing of products,

they may still be held accountable for selling a faulty item. In product liability lawsuits,

the injured consumer is not required to pick one defendant over another. Any part in the

product's chain of distribution can be named as the defendant in a defective product

lawsuit.

Injured consumers should remember that when bringing a product liability claim

against a retailer, they do not have to be the buyer of the product. For instance, if an

individual became ill after taking improperly manufactured aspirin supplied by a friend or

co-worker, they are not prevented from filing a product liability claim against the retailer

simply because they did not personally purchase the item.

Likewise, the injured party does not have to be the user of the defective product

and may be able to recover compensation for used products depending on the nature ofthe defect, product type and applicable state product liability laws.

c) Wholesaler or Distributor

Wholesalers, distributors and suppliers are the "middlemen" in between the

manufacturer and the retailer. These parties are part of a product's chain of distribution

and therefore may be found legally liable in a defective product lawsuit.

Dealing with defect product after it being sold

As history has repeated itself over and over again, injuries of any kind that are due to the

fault of defected products from a company can lead to million dollar law suits, an effect on a

business reputation, decline in customer satisfaction and ultimately putting the company out of

business.


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SurveysPlease tick the answer for every each and every question:

Age : _1_ Below 18_10 Between 18 to 25 _7_ Between 26 to 40 _2_ Above 40

Gender : _14 Male _6_ Female

Occupation : _11 Student _9_ Worker

1. Have you ever found a defective product throughout your life?

_17 YES _3_ NO

2. Have you ever complain about this defective product?

_7_ YES _13 NO

3. If YES does the company reply your complaint?

_5_ YES _15 NO

4. What are the ethical actions that need to be carried out by a company that faces with this

dilemma?

_6_ REVEAL _15 REPLACE _19 APOLOGIZE _0_ DO NOTHING

5. The company should be responsible for the defects of their product before or after their productis launched?

_18 BEFORE _2_ AFTER

6. Should they stop producing the product?

_13 YES _7_ NO

Comments:

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

Thank you for your time!


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Graph

Graph of the survey

Graph of the questioner

0

2

4

6

8

10

12

14


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FIGURE 1

FIGURE 2


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Analysis

A survey was done, and the statement above was discussed and analysed. Based on the survey

that has been done between the age of below 18 and above 40 in a total of 20 consumers regarding

defective products, it is proven that majority of the consumers have experienced buying or owning a

defective product. With the ratio of 17:3 consumers that agree that many of the products bought are

mostly defective, only 3 complained to the company and the rest did nothing. Based on a few of the

comments given by most of the consumers that did not complaint, it was clearly written that they did not

complaint because they knew that the company will not take action to any of their complaints. As stated

in the survey received, only 5 people were satisfied that their complaint was replied by responsible

companies and the rest did not get any reply.

The ethical actions that need to be carried out by a company that face this dilemma includes

revealing the defects of their products made, replace the defected product with a new one (provided that

its still under warranty) , apologize or do nothing at all. As analyzed, the consumers obviously prefer

that the defected product should be replaced and the company should apologize to the consumer. Only 6

surveyors responded that the company should reveal their mistake.

From the opinions that were given by the consumers, 13 surveyors do not agree for the

irresponsible companies to continue producing the defected products. And the rest thinks that the

product should continue to produce. This is because, based on the comments written, continuous

defected products should stop producing because it will cause loss to the company as well as the

consumers who got tricked my the irresponsible companies. Therefore, it is better to just stop

producing defected products or at least improve in the skills and ability of good quality product-making.


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Case Studies

Case study 1:

Toyota Products Failure

Toyota has long been recognized as an industry leader in manufacturing and production.

Toyota's management philosophy has evolved from the company's origins and has been reflected in the

terms "Lean Manufacturing" and Just in Time Production, which was

instrumental in developing Toyota's managerial values and business

methods collectively known as the Toyota Way. In 2010, the Toyota

Motor Corporation ranked first by the International Organization of

Motor Vehicle Manufacturers OICA with 8.6 million units producedglobally.

AIMS AND OBJECTIVES OF THE RESEARCH:

Over the past few decades, the overlying mission of The Toyota Motor Corporation has been to

"develop and provide innovative, safe and outstanding high quality products and services that meet a

wide variety of customers' demands to enrich the lives of people around the world

In order to uphold the TMC mission, specific goals and objectives have been identified as the

aim of the company in keeping with its beliefs and building on its prior sales and financial success.

The three main corporate goals are the following:

a. To steadily increase corporate value as a top management priority,

b. Continue to introduce and produce products that fully cater to customer needs, and

FIGURE 3 GOOGLE IMAGE


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Toyota, since then has been struggling to regain its once solid reputation among buyers for

producing reliable vehicles. The biggest damage to Toyotas image has been in the U.S. where its

response was seen as dallying.

The ballooning number of quality problems that add another dent to its tarnished reputation

especially in the crucial U.S. market, along with the other markets in which the company operates

globally.

FIGURE 5 GOOGLE


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Case study 2:

The Space shuttle Challenger AccidentThe explosion of the space shuttle Challenger is perhaps the most widely-written about case in

engineering ethics because of the extensive media coverage at the time of the accident and also because

of the many available government reports and transcripts of congressional hearings regarding the

explosion.

The case illustrates many important ethical issues that engineers face: What is the proper role of

the engineer when safety issues are a concern? Who should have the ultimate decision-making authority

to order a launch? Should the ordering of a launch be engineering or a managerial decision? This case

has already been presented briefly, and we will now take a more in-depth look.



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RESEARCH BACKGROUND:

The space shuttle was designed to be a reusable launch vehicle. The vehicle consists of an

orbiter, which looks much like a medium-sized airliner (minus the engines!), two solid-propellant

boosters, and a single liquid-propellant booster. At takeoff, all of the boosters are ignited and lift the

orbiter out of the earths atmosphere. The solid rocket boosters are only used early in the flight and are

jettisoned soon after takeoff, parachute back to earth, and are recovered from the ocean.

They are subsequently repacked with fuel and are reused. The liquid-propellant booster is used to

finish lifting the shuttle into orbit, at which point the booster is jettisoned and burns up during re-entry.

The liquid booster is the only part of the shuttle vehicle that is not reusable. After completion of the

mission, the orbiter uses its limited thrust capabilities to re-enter the atmosphere and glides to a landing.

The accident on 28, 1986 was blamed on a failure of one of the solid rocket boosters. Solidrocket boosters have the advantage that they deliver far more thrust per pound of fuel than do their

liquid-fuelled counterparts, but have the disadvantage that once the fuel is lit, there is no way to turn the

booster off or even to control the amount of thrust produced. In contrast, a liquid-fuel rocket can be

controlled by throttling the supply of fuel to the combustion chamber or can be shut off by topping the

flow of fuel entirely.

In 1974, the National Aeronautics and Space Administration (NASA) awarded the contract to

design and build the solid rocket boosters for the shuttle to Morton Thiokol. The design that was

submitted by Thiokol was a scaled-up version of the Titan missile, which had been used successfully for

many years to launch satellites. This design was accepted by NASA in 1976. The solid rocket consists of

several cylindrical pieces that are filled with solid propellant and stacked one on top of the other to form

the completed booster. The assembly of the propellant-filled cylinders was performed at Thiokols plant

in Utah. The cylinders were then shipped to the Kennedy Space Center in florida for assembly into a

completed booster.

A key aspect of the booster design is the joints where

the individual cylinders come together, known as the field

joints, illustrated schematically in Figure 2.2. These are tang

and clevis joints, fastened with 177 clevis pins. The joints are

sealed by two O-rings, a primary and a secondary. The O-rings



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are designed to prevent hot gases from the combustion of the solid propellant from escaping. The O-

rings are made from a type of synthetic rubber and so are not particularly heat resistant. To prevent the

hot gases from damaging the O-rings, a heat-resistant putty is placed in the joint. The Titan booster had

only one O-ring in the field joint. The second O-ring was added to the booster for the shuttle to provide

an extra margin of safety since, unlike the Titan, this booster would be used for a manned space craft.

Early Problems with the Solid Rocket Boosters

Problems with the field-joint design had been recognized long before the launch of the

Challenger.When the rocket is ignited, the internal pressure causes the booster wall to expand outward,

putting pressure on the field joint. This pressure causes the joint to open slightly, a process called joint

rotation, illustrated in Figure 2.3.

The joint was designed so that the internal pressure pushes on the putty, displacing the primary

O-ring into this gap, helping to seal it. During testing of the boosters in 1977, Thiokol became aware

that this joint-rotation problem was more severe than on the Titan and discussed it with NASA. Design

changes were made, including an increase in the thickness of the O-ring, to try to control this problem.

Further testing revealed problems with the secondary seal, and more changes were initiated to

correct that problem. In November of 1981, after the second shuttle flight, a post launch examination of

the booster field joints indicated that the O-rings were being eroded by hot gases during the launch.

Although there was no failure of the joint, there was some concern about this situation, and Thiokol

looked into the use of different types of putty and alternative methods for applying it to solve the

problem. Despite these efforts, approximately half of the shuttle flights before the Challenger accident

had experienced some degree of O-ring erosion. Of course, this type of testing and redesign is not

unusual in engineering. Seldom do things work correctly the first time, and modifications to the original

design are often required.

It should be pointed out that erosion of the O-rings is not necessarily a bad thing. Since the solid

rocket boosters are only used for the first few minutes of the flight, it might be perfectly acceptable to

design a joint in which O-rings erode in a controlled manner. As long as the O-rings dont completely

burn through before the solid boosters run out of fuel and are jettisoned, this design should be fine.

However, this was not the way the space shuttle was designed, and O-ring erosion was one of the

problems that the Thiokol engineers were addressing.


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The first documented joint failure came after the launch on January 24, 1985, which occurred

during very cold weather. The post flight examination of the boosters revealed black soot and grease on

the outside of the booster, which indicated that hot gases from the booster had blown by the O-ring

seals. This observation gave rise to concern about the resiliency of the O-ring materials at reduced

temperatures. Thiokol performed tests of the ability of the O-rings to compress to fill the joints and

found that they were inadequate. In July of 1985, Thiokol engineers redesigned the field joints without

O-rings. Instead, they used steel billets, which should have been better able to withstand the hot gases.

Unfortunately, the new design was not ready in time for the Challenger flight in early 1986. [Elliot,

1991]

The Launch

Contrary to the weather predictions, the overnight

temperature was 8F, colder than the shuttle had ever

experienced before. In fact, there was a significant

accumulation of ice on the launch pad from safety

showers and fire hoses that had been left on to prevent the

pipes from freezing. It has been estimated that the aft

field joint of the right-hand booster was at 28F.

NASA routinely documents as many aspects of launches as possible. One part of this monitoring

is the extensive use of cameras focused on critical areas of the launch vehicle. One of these cameras,

looking at the right booster, recorded puffs of smoke coming from the aft field joint immediately after

the boosters were ignited. This smoke is thought to have been caused by the steel cylinder of this

segment of the booster expanding outward and causing the field joint to rotate. But, due to the extremely

cold temperature, the O-ring didnt seat properly. The heat-resistant putty was also so cold that it didnt

protect the O-rings, and hot gases burned past both O-rings. It was later determined that this blow-by

occurred over 70 of arc around the O-rings.

Very quickly, the field joint was sealed again by products of the solid rocket-propellant

combustion, which formed a glassy oxide on the joint. This oxide formation might have averted the

disaster had it not been for a very strong wind shear that the shuttle encountered almost one minute into

the flight. The oxides that were temporarily sealing the field joint were shattered by the stresses caused

by the wind shear. The joint was now opened again, and hot gases escaped from the solid booster. Since



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Case study 3:

Common Incident: Furniture

Furniture is everywhere. We have tables, chairs, sofas and coffee tables in our homes, as well as

desks, office chairs and coat stands in our workplaces. Without realizing it we rely on furniture to,

sometimes literally, support us. When it doesn't and we suffer personal

injury as a result, we may be entitled to make product liability claims.

It is amazing how, with only slightest manufacturing fault, something

as seemingly innocuous as a bar stool can turn from a comfortable

perch to a source of pain and suffering.

RESEARCH BACKGROUND:

Unfortunately, for one 66-year-old man from Barnet, Greater London, the reality of just how

damaging such a defect can be hit home when, in July 2005, he was sitting at his newly installed home

bar, enjoying a pint of homebrew, and his stool collapsed. He'd only had the stool for a few weeks, had

paid more than 200 for its trademark design, and never imagined that it would cause him personal

injury and give him grounds to make a product liability claim. The impact of the fall left the 66-year-old

former surveyor with a f ractur ed coccyx and severe brui sing, for which he needed chiropractic

treatment. This treatment, however, was not enough to cure the lasting pain and discomfort of his injury.

Eventually, nine months later, a leading acupuncturist helped him fully recover from the injury.

Fortunately, for the safety of the public at large, the stool was not in mass production but instead

was only a limited edition design made by a small but prosperous designer. Three days after the

accident, the retiree decided to contact the manufacturer of the stool to let them know of both the

defect and his injury. Although the manufacturer at first expressed grudging sympathy for the man's

injury, when the question of compensation arose, they became defensive and suggested the man' s

weight was to blame for the stool.



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girlfriend what had happened and asked her to take him to the dental department.

A dentist examined him and told him that as a result of biting into the stone which was in his

packet of nuts he had two broken molars, one at the top and one at the bottom. He also explained that

the pain that he was experiencing was emanating from damage to his gum at the back of his

mouth and an exposed nerve that needed immediate dental care. The dentist cleaned up the mouth,

treated the injuries as best he could, temporarily fixed the broken teeth and instructed the young man to

make an emergency appointment to see his own dentist for further work to be carried out.

After seeing his own dentist and receiving the hefty bill for the dental work he decided that he

wanted to make a product liability claim. Within a few monthshe received a satisfactory of fer of

$3,800 in compensation from the snack manufacturer to cover pain and suf feri ng, lost earn ings and

the dental work that he had undergone. He was not charged a single penny for any costs or fees that

accumulated from his case and he got to keep 100% of compensation that he was awarded.

FIGURE 13 GOOGLE IMAGE FIGURE 12 GOOGLE IMAGE


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ConclusionAs conclusion, in everyday life, we were facing many problems due to human error. We just

cannot simply blame the engineer or anyone involve 100%. There is sometimes when consumers or

buyers just lack of knowledge to identify the defective products or rather they simply bought things as

their pleased. And major problem came in as our statistics shows that almost 75% of people do not

report about the defects. If they would encourage everyone to do the report if any, there will be less

chances of product defects in market.

Thus as focusing on an engineer, there are several duties that shall be fulfilled. The first duty is

to hold paramount safety, health and welf are of the publ ic.Besides that, they have to perform services

only in areas of their competence and issue a public statement only in an objective and truthful manner.

The most important is they have to avoid decepti ve acts and conduct themselves honorably,

responsibly, ethi cally and lawfu ll y to enhance the honour reputation and usefu lness of the profession.

Therefore, it is better to just stop producing defected products or at least improve in the skills and

ability of good quality product-making. Thus,engineers should be responsible for the defect that

happened on their product to ensur e the safety of all consumers and buyers around the world.We can

also relate this project report as the saying said that; preventing is better than cure.


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ReferencesWhile conducting this portfolio, we have done some research from the internet. Here are the lists

of websites that we have surfed to gain the information:

http://www.ibe.org.uk/userfiles/op_trustcasestudies.pdf

http://www.nspe.org/Ethics/CodeofEthics/index.html

http://www.rcs.k12.va.us/engineer/Unittwo.pdf

http://www.forthepeople.com/parties-responsible-for-a-defective-product--1-1588.html

http://www.los-angeles-injury-lawyer-blog.com/2009/09/

classes.soe.ucsc.edu/.../Engineering

jee.org/1996/April/101.

www.springer.com/social+sciences/applied+ethics/journal/11948

www.nae.edu/Publications/Bridge/EngineeringEthics7377.aspx


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Appendix

Documents

case study for engineering problem