Engineering: October 2008 Archives

In Defective Fasteners Drive Structural Failures ForensisGroup® expert witness John D. Pratt, Ph.D., P.E., discusses failures of mechanically-fastened joints:

Industrial fasteners are no less subject to quality or installation defects. Leaking roofs, sudden ladder and seat anchorage failures, corrosion, poor paint adhesion, and numerous other manifestations of poor fastener quality are avoidable with more attention to the manufacturing and installation details.

Poor fastener quality and installation practices are at the root of most, but not all, fastener failures. A misunderstanding as to how published strength allowables are established can also contribute to premature failure.

In Defective Fasteners Drive Structural Failures ForensisGroup® expert witness John D. Pratt, Ph.D., P.E., discusses failures of mechanically-fastened joints:

Structural failures can oftentimes be traced to a defective mechanically-fastened joint. For example, longitudinal and circumferential fuselage joints are among the most highly loaded parts of an airframe, subject to loading each time the aircraft is pressurized. Over many flight cycles improperly installed rivets can loosen, permitting microscopic movement between overlapping fuselage panels. Such movement leads to fretting fatigue cracks resulting in early failure. The highly publicized rapid decompression of Aloha Airlines flight 243 in 1988 resulted from such fatigue cracks along the fuselage joints. These cracks eventually grew long enough to connect with one another and catastrophic failure resulted.

While the Aloha Airlines case represents a failure of maintenance and engineering personnel to anticipate the impact of multi-site fatigue damage, there are in fact many causes of premature joint failure, ranging from inadequate supplier quality control to defective installation practices.

Hiring the right construction engineering expert witness will provide proof and testimony in court to support your case.  In Tips For Selecting The Right Expert Witness Service (Skynewswire.com), Rosie Fletcher writes:

5. Training and Workshops Attended

Believe it or not, there are trainings, workshops and seminars offered to help expert witnesses improve in their line of work. These additional classes will help expert witnesses attain their goals in a more effective and efficient manner.

6. Paying the Right Price

Of course, expert witness services come in a range of prices. Their rates depend on the amount of experience they have and the extent of work theyll be expending for your case. Its your call if you wish to go over your budget and secure a favorable outcome of your case.

7. Reputation Matters

Lastly, although its you who have hired the expert witness, he must still remember and understand that his primary duty is to help the court seek the truth. Thats why his reputation matters as well. If hes known to take bribes and make dishonest or biased claims in favor of the hiring party, his professionalism will surely be questioned in the court room. In the worst case scenario, his opinion would be rendered invalid and youll end up having hired him for no reason.

Hiring the right construction engineering expert witness will provide proof and testimony in court to support your case. In Tips For Selecting The Right Expert Witness Service (Skynewswire.com), Rosie Fletcher writes:

Even if you don't need to hire the right expert witness service now, you could need one later so its better to be prepared in advance. The expect witness service you'll avail of must meet the following criteria:

3. Achievements and Credentials Although titles don't define a person, they do carry significant weight in the court room. Consider this: if a jury is debating on the quality of education being provided by a certain school, that type of expert witness will they be more inclined to believe one who has sufficient experience in teaching and have a long list of professional credits and certification to his name or one who has simply had the benefit of graduating from high school? It may not be fair but that's how the world or more specifically, the law works. Knowing this, why hire one who doesn't have enough credentials when you can hire an expert witness that has them?

4. Degree of Involvement in an Industry If you are looking for an expert witness to help you win a dispute over a real estate property, you will do better if you hire an expert witness who happens to work in the real estate industry as well. Being an active member of the industry helps the expert witness become a better judge and adviser. The expert witness doesn't rely on his observations and analytic skills alone to render a judgment; his actual work experience helps him greatly as well in coming up with valid and accurate results.