Saturday, May 16, 2015

Static Air Tubing Creates Conflict With Flaperon Mixer Arm

Was so hopeful to finish off dressing the center tunnel wiring run today … but that was not to be.  The work session began with a small redo of the wiring under the flap handle. The F-00050 wire routing bracket is much like a shoe and presses down on the wiring run preventing the wires and tubing from rubbing on the bottom of the flap handle. During the initial fitting, was not happy with the way a couple of the wires passed underneath the F-00050 bracket so removed the flap handle assembly and rearranged the wires more to my liking. Did not tighten the flap handle mounting bolts at this time because the bracket I made a while back to allow the static line to run above the flap handle’s mounting block needs priming.
After a small redo of the wire run under the flap handle, the F-00050 is in place and ready to be secured with the mounting bolts.

With the F-00050 wire routing bracket in place under the flap handle, it was time to move on and install the two forward system blocks and the F-00049 wire cover plate which is placed on top of the wires and held down by the F-1276D system blocks. This is where the wheels fell off … so to speak. The wiring was dressed and the F-00049 wire cover was slid under the flaperon mixer arm and over the wires. The F-00049 wire cover scraped the underside of the flaperon mixer arm big time and causing binding of the mixer arm.  Quite a few attempts were made to rearrange the wires with and without wire ties, along with moving the static tubing around … just could not find a sweet spot where there was not rubbing between the mixer arm and the F-00049 wire cover. The obvious conclusion was even though the extra static line tubing physically fits in the system blocks, the wires and tubes do need to ride up on one another and this takes precious clearance away from the flaperon mixer arm … which, at best, just barely clears the wires when they are pressed down with a finger.
The F-00049 wire cover’s sides are bent to 45 degrees. It is installed between the two forward most system blocks and under the flaperon mixer arm.

Moving to plan B: A contingency plan was already formulated months ago for the static line. So put plan B in motion by removing the static line from the system blocks and rerouted the static line alongside the pilot’s seat rib. No additional holes were drilled … existing holes in the seat rib were used to secure the static line with wire ties. The static line was touching the edge of a lighting hole flange. So a piece of vinyl tubing was used as a protector by placing the static line inside the vinyl tube and then securing the tubing onto the lightening hole with a wire tie. This can be seen in the photo below if one looks closely.

Return from the future: Moving to plan C: After installing the left F-1265 flaperon pushrod, much to my surprise, it was discovered during full stick deflections the left flaperon pushrod would touch the static air line at the point of the right edge of the small lightening hole on the right seen in the photo below. The static air line will be moved to the backside of the rib it is currently attached onto. The same positioning will be used and the same mounting holes for the tie wraps. The static line will be routed through the small lightening hole in front of the flap handle mounting block and pass back through the large lightening hole in the forward portion of the seat rib. This will be an easy fix.
Static line attached onto a seat rib. The blue bracket to the left on top of the flap handle mounting block is just sitting in place to show where it will sit … but first it needs to be primed before final instillation. The vinyl tube around the static line is for protecting the static line from becoming damaged from the edge on the lightening hole flange. Due to interference with the F-1265 flaperon pushrod the static air line will be moved to the backside of this rib.

New home for the rerouted static line. The static line appears to be rubbing on the flange of the large lightening hole … but it is not. Due to interference with the F-1265 flaperon pushrod the static line will be moved to behind this rib but follow the same path and use the same wire tie locations.

Ran out of shop time so did not try to install the F-00049 wire cover under the flaperon mixer arm now that the static line is no longer part of the wiring run. I don’t anticipate any problems because only the pitot tube and stock RV-12 wires are left under the flaperon mixer arm.