Cockpit ergonomics are a big deal to me – and they are a slippery problem. I spent much of a career helping designers refine designs for man-machine interfaces, and part of the problem we had is that everyone had different opinions of what was “good.” And given the wide variety of people – both in size and shape as well as the way they think – coming up with good solutions was never easy.
When we joined forces with the original builder of our Dream Tundra and became partners in the project, he already had stick grips installed. They were the black, cylindrical grips with buttons on the top that many builders use. In fact, I have one on the rear stick of my RV-8. I was very satisfied with the choice – right up until we got into the flight test phase, when I found that the large airplane’s trim requirements on a go-around were fairly hefty. Full nose up trim was required for a good landing, and if you decided to “go” from that configuration, you found yourself pushing considerably on the stick to prevent the nose from coming up too far until you could get the trim back down.
Unfortunately, my middle-of-the-road sized hand and fingers had a tough time pushing forward while at the same time reaching over the top of the grip to push the nose down button. In fact, I usually had to take my other hand off the throttle and use that to trim the airplane. Not desirable, and not good ergonomics.
Enter the grips from Tosten manufacturing. Kevin Williamson, the owner and designer at Tosten, has been marketing a modular grip for a couple of years. This grip features a little bump-out thumb rest that can be positioned on either side of the rip (for righties or lefties). I challenged him to find a trim switch that could go on the grip so that you could firmly grasp the stick while still trimming with your thumb – no repositioning required. He delivered these to me while the airplane was down for modification, and the installation was fairly straightforward. Our Tundra is not a complex plane, so many of the buttons are currently unused – but I am happy to report that the thumb trim on the side of the stick works perfectly – unless I resort to my early learning and try to reach for the top! I suspect we can sort that out with a little experience and retraining (hopefully electrical shock reinforcement won’t be required).
The truth about ergonomics is that two different answers might satisfy two different people – and neither of them will actually be “wrong.” We design for the safest approach for the wide variety of pilots, and while there are some absolute truths, there will always be differences of opinion on what is “best.” The most we can hope to do is come up with designs that are safe for everyone, and best for most. I this case, the new grips from Tosten seem to be a good solution for our particular design problem.