Stress Without Tears: A Primer on Aircraft-Stress Analysis Requiring No Advanced Mathematics. [Paperback]

Stress Without Tears covers structural design and analysis. They are the perfect complement to each other (along with Basics of R/C Model Aircraft Design) and will provide an excellent grounding in aeronautical design for the non-engineer. (They are also a very good refresher for the engineer).

Why am I making this recommendation? The reason is that a lot of the same questions and discussions spring up on message boards on which I participate. Just recently we have had all kinds of questions about ailerons, flaps, wing spars, struts, etc.

All of these questions are design-related. That is to say, the builder is wondering how best to build the airplane and the plans either don't show the detail in enough specificity, or the builder has an idea for "improving" his plane.

It is a fact of life that no two builders build the exact same plane, even if it is from a kit. Every builder does things a little differently. With plans this is even more true, especially if the plans leave a lot of the detials open, as is the case with the Ragwing plans that I have seen.

So the builder ends up with a lot of questions. Even if you intend to follow the plans to the letter and the plans show every little detail, the questions are still there because it is human nature to be curious about how things actually work and why they work that way.

I am confident that every airplane builder will greatly appreciate these two books and will enjoy the increased knowledge they get from studying through them. Knowledge really is power, and when you are able to figure out a question on your own, you feel a true sense of discovery.

Once you've mastered aerodynamics and flight mechanics with "Aircraft Design," you can turn to structures. That is the subject of "Stress Without Tears," and it does a beautiful job. Again, it is aimed at the non-engineer and makes a technical subject very understandable. The book covers just about everything one needs to know about aircraft structures -- starting with loads calculations, spar strength, sizing, analysis, etc. It covers a number of different materials, from wood, to tubing, to sheet aluminum.

The author, Tom Rhodes holds a PhD in aerospace engineering and worked on the design team for some of the earliest jet fighters. He is eminently qualified to write this book and he does a great job of explaining the concepts in a very understandable way.

Each chapter is really more of an "article." This book sprang from a series of articles from Kit Planes magazine.

This book is not meant to be aerospace engineering textbook. However, if you study through these and you want to go further, then you will be able to pick up an engineering book and actually understand it. I have a good library of engineering books and I can tell you that this book contains most of what is in those big, dense engineering books -- minus the theory.

Let me explain what I mean by that. For example if you take a college textbook on flight mechanics, you will learn about the equations of motion that govern an airplane's flight through the air. (Btw, the word "mechanics" in this context does not mean someone who repairs a car or an engine; "mechanics" is the discipline of physics that studies the motion of objects -- big difference).

The flight mechanics textbook provides the theory that starts right from Newton's Laws and shows how the equations are derived. This involves a lot of calculus, which is fun and interesting only to those who love math. This is important for the scientist and engineer because it PROVES, scientifically that those equations are actually valid.

As a non-scientist, you do not really need to prove those equations to yourself. We just accept that they are factual and true. So when these two books tell us how do do an aerodynamic calculation, or a stress calculation, they skip all of that scientific theory and complicated math and explain it in a a way that is intuitive and makes sense. The bottom line is that you still learn the same equations that you learn in the textbooks. You just don't learn the science behind them and the complicated derivations.

The result is the same, since most engineers quickly forget those theoretical derivations anyway -- once the exams are out of the way. But it is the actual equations for figuring out aerodynamic and structural problems that are the tools that you continue to use.

I will also underline that any learning that you accomplish is directly proportional to the effort you put into it. Picking up this book is not going to be like reading through a fluffy magazine. You actually have to think about what you are reading and maybe take notes and make drawings. But it is a lot of fun too.

Regards,

Gordon.

This book has an excellent balance of easy to use approaches up front with deeper subjects for those who want that near the end.

I heard about this book on aviation history magazine. I did not find it very useful for understanding the mechanics of stress analysis. I supposed the writer did not have a long career in aircraft design, and this turned out to be true.