It's funny how little things can make a huge difference in life--especially when it comes to aviation. Little things are important to aircraft design, and there are few things in an airplane that we can take for granted. Take, for instance the simple matter of finding a stick grip that works well for a particular airplane. You see--stick grips don't just match your hand (although that is important), they also need to work with the plane!
We had a particular problem with our Tundra during flight testing – we found that it takes nearly full up trim to land when you are solo or just have a pilot and front seat passenger. For takeoff, you want the trim about neutral. If you have to go around, or do a touch and go, the difference between the two positions is fairly dramatic in terms of stick forces – you found yourself pushing fairly hard to keep the nose from rearing up until you get the trim back to a nose-down position. The problem was that the stick grips that had been installed years ago were for a rather large hand, and featured two buttons on the top, one for nose down, and one for nose up. There was virtually no way to push the nose down button with an average sized hand/thumb while still pushing forward on the stick. This meant you had to take your other hand off the throttle and use one of those fingers to trim the airplane.
The problem was solvable by a couple of methods. One would have been to put an additional trim toggle near the throttle. But the one we chose was to look for a grip that didn’t require you to move your hand/finger/thumb position to re-trim. Easy…until you find there are almost no grips set up to work that way. Ideally, your thumb should rest on a shelf, so that you wrap your hand around the grip in a natural position. Most “military style” grips have the trim switch on top, in the center – this requires lifting your thumb up in a bit of an unnatural way. I know – I’ve got numerous military style grips on several airplanes, and while they work, they aren’t ideal.
So what do you do, short of carving a custom grip out of a block of metal, wood, or plastic? We called up Kevin Williamson at Tosten Manufacturing, and challenged him to configure a grip exactly the way we wanted it – with a trim button on the thumb shelf. Tosten makes a customizable grip that allows pilots to pick right or left hand versions, whether or not to have a shelf for the palm, and to decide if they want a thumb rest or not. Up until now, the thumb rest could be configured with just a push-button for a single function. But with a little whining on our part, Williamson fitted a single-axis, two-position trim switch on the shelf, just for pitch. With the regular array of switches on the top of the grip, we’re going to be challenged in return to find functions for all (or even most) of the buttons.
The beauty of the grip is that it fits the hand, and allows one to reach all of the needed buttons without repositioning the hand – the perfect answer to our little problem.