Over the past couple of weekends I've been concentrating on making mockups of the little parts that make up the control system inside the wing. There's two bellcranks for the flaperons, one bellcrank for the airbrakes, and of course the arms and funnels for the control auto-connections at the wing-to-fuselage junction.
On 11 January the conditions were perfect for a bit of rock climbing, so Alia and I went in to Yosemite to knock off a few pitches at the Manure Pile buttress. There was snow on the ground and the sun wasn't even on the first pitch when we arrived, but it was T-shirt weather from the second pitch on up. Here we are back at Jefferson Airport. That's the Sentinel behind me and Half Dome peeking around the corner on the left.
On 17 January, testing possible locations and orientations for the jettison locking bar.
The T-bone, cradle, and jettison hood in action.
On 18 January, laying a nice thick bead of shmoo around the bonding flange of the #2 bulkhead using a ziploc baggie with one corner snipped off. When you do this, reinforce the corner with masking tape or duct tape before snipping it. That prevents the corner from tearing wider under the extrusion pressure.
Pressing the bulkhead into place. Once located, I clamped the bulkhead in location with four clecos in holes drilled through the bulkhead and through the fuselage shell. I don't worry about cleco holes here and there, the strength and stiffness of these structures is distributed well enough that a few voids like these have little consequence. The one issue I experienced is that drilling the upper right hole I went through the shell into my left leg, perforating my prototype red "YOU MAY DIE TODAY" sticker. Fortunately I didn't hit anything vital.
Between taking photos and standing by to call 911 in case blood came in spurts, Alia spent most of the time riding my bicycle and tweeting on her new phone.
Starting the control system mockup prototypes. I originally thought that the Hanle-type funnels were too complicated to emulate, but at this point they seem to be the simplest solution, so I'll put my effort into developing jigs to manufacture them cost-effectively.
Homebuilt aviation is not for folks who don't try things at home.
page updated 21 January 2009 all text and graphics copyright (c) 2009 HP Aircraft,
LLC