Some Messy Stick Details

Our intent was to use the  Ken Brock stick from the prototype but with a few minor enhancements.

• First, the original stick had gotten a bit sloppy over the years due to wear, so we had the factory send us a new set of walking beams. That, and new hardware, got rid of any unneccesary play in the mechanism.

• Originally stick had been painted black, so I used paint stripper to remove the old finish. That let me carefully check the stick of any signs of stress and it passed just fine. The stick was included in all the parts that went out to the anodizer and it came back looking just the same as all the other airframe pieces.

• Now that we were based at a county airport, regular radio use would be the norm. To facilitate this, we wanted the PTT switch in the stick. The G101 stick grip (see left) from the Ray Allen Companyfilled the bill without breaking the bank ($32 for the grip, switch, and adapter rings to handle different stick diameters).

• A chamfered 1/4-inch hole was drilled in the bottom of the socket that holds the base of the stick assembly. This provided an exit point for the pair of wires from the PTT switch, which were then soldered into the Comtronics radio harness.

The first pass at assembling and installing the stick was purely for fit, so I skipped applying any lithium grease to the mounting pivots or the walking beam bolts. I was only part-way through the installation when I realized I had big problems, but elected to push on just to see how bad the problems might be!

While I was sure that the seat was just as high as it had been on the prototype, there was essentially no room for movement of the stick and the associated walking beams. The problem wasn't the position of the stick, but rather the fact that the seat pan comes in contact with the stick well below the bend designed to increase the stick travel (left above). Compare this with the prototype 'Bee where the seat pan contacts the stick at the furthest extent of the bend (below). Note that in both aircraft, the control yoke is very close to the rear edge of the seat braces.

The only practical solution seemed to be to move the seat up about three inches. The photo below shows the seat, offset upward by one set of mounting holes. This not only moved the seat up, but also slightly to the rear, due to the angle of the seat mounting rails:

Although the seat looks as if it were mounted, it is simply pinned in place with two bolts to check stick clearance. The stick now appears to have a normal range of motion!  If you will be using a Brock stick, I would advise installing the stick prior to mounting the seat! Yet another problem is that the aluminum plates for anchoring the seat belt fittings are now blocking lateral movement of the stick. They will have to go and I will have to think of yet another way to anchor the seat belt! Why is it that nothing ever is as simple as you think it should be!

Remounting the seat will require that we drill one more mair of mounting holes and that we make a new set of forward mounting struts. However, now that the seat is off, I'm going to paint it bright yellow as I have developed a distinct aversion to the red! This will give me something to do while awaiting the arrival of the new angle stock from Aircraft Spruce! Anyway, it should look reasonably good with the black seat and back cushion from Star Bee.

UPDATE - 9 May 2006

The seat has been painted and remounted, including new front support struts. The yellow paint job looks fine on the outside but only so-so on the inside seat pan. I think the best solution to the problem is a custom seat cover. The local guy I want to use is on vacation until 15 May, so I elected to get the seat back on the gyro so as to not lose any more time. I am ordering another seat from Star Bee for the seat-cover guy to use it as a pattern. I am going to as him to save the specs so that other Star Bee builders can order one if they turn out well. Since this may well be my final gyro project, I'm going to use leather, but I will ask him to spec  the cover in both leather and vinyl. Pictures when available!