An unexpected lesson in success [Part 2]

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An unexpected lesson in success [Part 2]
Miscellaneous Musings from the Technical Director

Monday, 10-DEC-2007 by Donald MacPherson - HydroComp Technical Director

Last spring, I was asked to adjudicate a student design competition, where one of the review questions in determining which group was most "successful" was to determine if the groups "Exceeded", "Met", or "Did not meet" expectations. My immediate question was, "What were the expectations?". During our interviews with the students, it became very clear that each judge had a different definition of success and expectation. Some viewed success as a true product deliverable (i.e., "Did the product actually work?"). On the other hand, I was viewing success and expectation from a student learning perspective.

One project group was very well funded and produced a very polished presentation about a "Phase 2" update to an amphibious vehicle originally designed and built by a prior group. The updated vehicle ran well, and was a solid product. Another project group had virtually no funding, and their project deliverable was not a physical product, but a design summary for a novel aquaculture system. They had started from a clean sheet of paper, and while the basic design was sound, they had some fundamental engineering deficiencies in the details.

So, which project was more "successful"? Which "Exceeded" expectations? As it turned out, the latter group actually won the competition - much to their own surprise and the chagrin of other groups and advisors. They simply had an academic problem to solve, and they fundamentally did so. Their omissions were in details that could be easily resolved. The other group took an existing project and added to it. They were not required to "discover" anything new and assumed very little risk. As a result, the judges eventually agreed that the greatest "student design" achievement was by the team that covered the most new ground. The measure of success for each individual involved in this competition was fully and completely driven by expectations.

We should not be surprised to see a lack of clarity in "client expectations" in a student competition, but it is unacceptable from "fully baked" engineers. Yet, most of the forensic projects we encounter at HydroComp have their initial problem with misplaced "expectations".

For example, I was recently asked to review drag predictions for a wheeled waterjet-driven amphibious vehicle. The client expected to reach speeds that seemed extremely optimistic to me. One fundamental problem was that there are no reliable drag prediction methods for a "box with wheels". The closest thing was a barge method, but even a barge is much more streamlined than something which is essentially all extended appendages. Normally, at this point, I would look to other vehicles for a simple parametric scaling, but here, too, we were hampered as there are no model tests or published full-scale tests for comparable vehicles. My concerns about extreme optimism were somewhat confirmed by looking at a very simple "transport efficiency" calculation. This vehicle would never reach the target speeds with the proposed installed power - or even twice the proposed power. It would be my conclusion that this project had no hope for success - as defined by the expectations - and I would have not taken on the project.

Optimism in attainable speeds is very common. I often find that I need to be a detective to determine how a client came to their selection of a proposed operational speed. In many cases, I find that bounding the solution with comparisons to other boats can make a reasonable case to help the client modify the expectations. If a client will not change, and I feel strongly enough about it, I will turn down the job. As I often tell clients, "I will give you my best answer regarding the physics involved, but sometimes the physical answer is simply not what you hoped to hear". Do not let untenable expectations go unchallenged.

We often make expectations based on risky gambles. Take the designer that believes that the shipyard will launch the boat at precisely the original design weight and LCG. Possible, but not likely. To set a design objective based on the expectation that a third party will "exceed" their own expectations is very risky. Again, possible but unlikely. If your success is linked to exceptional performance from some other person or organization, then you might as well be rolling dice in Las Vegas - you probably have better odds.

Now let me give you a counter-intuitive example - contract trial speeds. As unfair and unreasonable as it may be to base the validation of a ship's performance on a light-weight calm-water sea trial, the expectations are actually pretty clear. Specific objectives are well defined, and are quantifiably "exceeded", "met" or "not met".

Remember, you have no real control over the expectations of others. However, it is part of our responsibility as engineers to advise clients when their expectations are risky or unreasonable. We hope that we can help establish a responsible expectation that will satisfy the client - based on sound engineering rationale. In spite of this, of course, we will encounter clients who will not modify their expectations and take that risk. Then we must decide if we can be successful and deliver on that expectation.