Decision-Making in Building an Aircraft

March 2017 - They say that the toughest decision in building an aircraft is choosing the paint scheme. Well, that may be true, but there are lots of other decisions along the way.

In my career I was trained in, among other things, using a decision-making tool called the Kepner-Tregoe decision-making chart. If you’re familiar with spreadsheets, you might like to give it a try for building an aircraft, or for any other decision for that matter. The bigger the decision, the handier this tool seems to be.

It works this way: First, you pick out your candidates for your decision — if you are planning to build a kit, you may exclude any plans-built alternatives, finished aircraft, etc.— then put your candidates along the top line of your spreadsheet. Now down the side, you split your decision into two parts. The first part is go/no-go decisions. An example might be that an aircraft might look interesting but it has only two seats and you want four. No-go. Those no-go candidates get no further consideration.

Now comes the interesting part. Think of all the factors that affect your decision: affordability, quickness to build, reputation of manufacturer, performance of the aircraft, tricycle gear, and so on. Don’t be shy about adding lots of these considerations to the left side of your spreadsheet.

Create a new column next to the individual features under consideration, which we’ll call the “importance” score and will represent the relative importance of each item versus the others.

Now create two columns under each candidate for your choice. RV-7, Rans S20, Murphy Rebel, etc. These two columns will be how each candidate scores in your opinion: the multiple of the importance and the individual score for that choice. A scale of 1-10 seems to work well for the importance and also for how well a specific choice scores.

Simply going through a list that’s as thorough as possible in terms of features and their importance will be interesting in itself, but summing the scores for each choice at the bottom sometimes leads to surprising results.

I hope this method is of some interest to you if you are planning on building an aircraft. The last time I used it, I bought a house! Of course, it’s also possible to change your scoring to adjust to the choice you wanted in the first place, but at least you will know why you did it.