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The problem was entirely in the unbalanced flaperons and the inherited Seahawk control system. As you know, I redesigned the flaperons to be fully balanced. I also have changed ALL of the control system elements with the single tab arm on them to double tabs. The single tab was twisting under load because the rod ends were mounted on the side of the arm. In retrospect, I am really amazed that those single arms didn’t fail completely under some of the loads they experienced. With the double tab, the rod end is mounted between the two tabs and there is no twisting. This one thing alone took a great deal of the sponginess out of the system that was inherited from the Seahawk. The control system is now solid, and positive and moves freely.

Through testing, I found that the 5/8 flaperon torque tubes also inherited from the Seahawk were just too small. They were acting like torque springs and allowing the flaperons to flex up when meeting the airflow. For years people had been telling me that it didn’t look like I had any flaps pulled in when I was landing when I knew I did. It was because the flaps were flexing up that much! The new system is decidedly different.

You can SEE the flap drop easily even on short final with maximum loading and the flap effect on the flight characteristics is now dramatic.

Another part of the system I changed and cemented as final is the flap control and linkage. The old Seahawk cable system just left a lot to be desired. I always felt like the pulleys in that system were really over loaded when the flaps were engaged. It took a LOT of force to pull on that cable against those little pulleys. I designed a new ratcheting flap handle which operates a torque tube that extends from the center of the pilots seat (same place as the old one) over to the center console, between the C bulkheads. There it has a double tab CS-4 control arm, connected to a rod end and ½ aluminum push-pull tube which goes back just under the lower wing to a bellcrank at the back of the lower wing. That bellcrank is then connected to the CS-5 mixing plate which it operates.

This arrangement is very simple and positive and I don’t feel like I am about to rip something out of the plane when I activate the flaps. The handle has a very positive ratcheting mechanism and the ratchet engages very definite slots which give you preset flap settings. I have found that 30° of flaps is just too much for the plane under most circumstances. 30° takes the flaperons down so far that there just isn’t much left for roll control and the ground effect float becomes too strong. I like 10° for takeoff and strong crosswind landings, and 20° for normal landings. One of the things I like about the manual flap handle and this new setup is that when taking off on water, once I am on step, I can wait until I am running pretty good on the water and then reach down and pull in 10° of flaps and it will pop the plane right off! The first detent is 10° and the latch is spring loaded, so I can just pull the handle up and it automatically drops in at 10° in the wink of an eye.

Last year we finally got the new plane to Sun & Fun, but it didn’t have the real pretty paint job and we hadn’t yet had any fresh magazine coverage and we still had our cramped exhibit space and the plane had to be parked on the flight line. I had already been in Florida for 3 weeks in a motel, working long hours on the paint job and frankly, I was tired. On top of that, the day of the seaplane events, there was a fire south of the airport and the very high winds pretty well washed everything out at the seaplane base. Bert MaWhinney flew over to the base with me and we landed on waves that I was told later were 16 inches! We wallowed around on the water for a while trying to get into the shore, but the crosswind just wouldn’t let us. So, we took off back into the air. It was pretty rough as Bert will tell you I’m sure, but the Goose handled it rather well and we started back to the field only to find that it was closed due to the fires and smoke and wind. I went back to the lake and landed on the up wind end of the lake where it was a lot calmer and moored the plane for the night. The next day I returned and flew the plane back to the field. End result was that we didn’t get to show off the plane very much and it wasn’t really ready to be shown off anyway.

GLASS GOOSE GAZETTE * ISSUE #17, June 15, 2000
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