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With the Inside FMEA series of articles, my intention is to bring to life the subject of FMEA, and provide value to readers from all levels of experience.
Whether you are new to FMEA, or an FMEA expert, it is my sincere desire that each and every person who reads Inside FMEA articles will discover new insights about FMEA, and experience improved success in FMEA applications.
The first article, called “Welcome to Inside FMEA”, will introduce the series, and provide a glimpse of what is to come.
Readers are encouraged to contact me with any questions about FMEA, or feedback on Inside FMEA articles. Questions, feedback, and ideas for future articles can be sent to carl.carlson@effectivefmeas.com. I will personally respond to all questions and feedback.
I’m excited to bring this new series to Accendo, and hope you enjoy reading the articles, as much as I enjoy writing them. As I say to readers of my book, "best wishes for effective FMEAs."
Carl S. Carlson
Consider the recommended action “Review results of XYZ test to confirm requirements are achieved.” Is this a good FMEA recommended action to address a high-risk issue? Is it sufficient? Challenge your FMEA knowledge by solving this problem and other problems presented in this article.
Consider these questions: How many recommendations are needed to address the root cause of a high-risk problem? If the FMEA team is addressing an issue with high-severity and high-occurrence ratings, is it usual to have a single recommended action to reduce risk? Why not? Read on, to learn the essential elements of FMEA recommended actions, and answers to this questions.
“I have been impressed with the urgency of doing. Knowing is not enough; we must apply. Being willing is not enough; we must do.”
Leonardo da Vinci
One of the more important topics in the FMEA body of knowledge is how to audit the effectiveness of FMEAs. Performing FMEAs properly and to a high quality standard is essential to obtaining the best possible results. This FMEA Q and A goes to the heart of FMEA effectiveness audits.
“Without a good question, a good answer has no place to go.”
Clayton Christensen
In this article, we use problems and solutions to learn about FMEA controls. In the intermediate problem, we continue examining the door latch-pin failure of the DC-10 cargo door, as an example to identify FMEA controls. In the advanced problem, we analyze a fictitious FMEA relating to potential safety of someone trying to unjam a snowblower.
A common error in FMEA procedure is to make entries in the Controls column that the FMEA team believes need to be done, but are not currently planned or in place. Why is this error so prevalent? Maybe the question should be why do we limit entries into the prevention or detection control column to actions or methods that are currently planned or in place?
“Never mind your mistakes. One day they will become your most prized possessions.”
Abhijit Naskar
Is it a good idea to do one generic FMEA for wiring harnesses, and use it as a reference for other FMEAs for similar applications? What about interfaces? These questions are discussed and answered in this FMEA Q and A article.
“We live in the world our questions create.”
David Cooperrider
The DC-10 case study continues by asking for causes to the door latch-pin failure. The advanced problem poses a realistic and especially challenging circumstance that FMEA teams can experience.
“Judge a man by his questions, not his answers.” Voltaire
Does a cause description need to be a design or manufacturing deficiency? Why? This is one of the more important questions to consider if you want to achieve quality FMEAs.
“The effort to get at the truth has to precede all other efforts.”
Albert Einstein
In this Q and A article, a reader asks a challenging question about the linkage between FMEA boundary diagrams and Design FMEAs. There are many linkages between different elements of FMEAs, and this question/answer highlights one of the key linkages.
“In all affairs, it’s a healthy thing to hang a question mark on the thing you have long taken for granted.”
Bertrand Russell
Can you identify the effect of the door latch-pin failure in this case study? The loss of the aft cargo door on the American Airlines DC-10 aircraft will be the focus of this Problems and Solutions article. This real-life case study is being used to practice identifying FMEA elements.
Why do you think FMEA procedure requires effects to be taken to the system or end user? Why not describe the consequence only at the local level. If a bolt in a complex system fails, the parts that the bolt was clamping together may come apart. Isn’t that enough?
“Wisdom consists of the anticipation of consequences.”
Norman Cousins
In this Q and A article, a reader asks an interesting question about whether or not to update a System FMEA, when making subsequent changes to lower-level items. This is an excellent question, and shows the reader has good insight into the application of FMEA.
“Judge a man by his questions, not his answers.”
Voltaire
Whether you are new to FMEA or more experienced, these problems will challenge your skills. The intermediate/advanced problem uses an actual airline disaster to challenge readers with an FMEA problem, and practice identifying the elements of an FMEA.
Do you know why we ask for the “mode” of failure when performing FMEAs? This article will provide theory and practical examples of defining failure modes, and highlight an application tip that can improve your FMEA effectiveness.
“I haven’t failed, I’ve just found ten thousand ways that don’t work”
Thomas Edison
In this question, a reader asks how to define system-level functions, and how they are different from subsystem and component functions.
“A prudent question is one-half of wisdom.”
Francis Bacon