The LONG Spar

I know, the picture isn't very good, and the lighting is poor--but there in the middle are the recently joined left and right spars for our nascent Xenos Motorglider--and if it were any longer, it would need two zip codes!

We spent the last week drilling up the tooling holes that are used to join the two overlapping spars, bolting them together, and then drilling and reaming for the two main wing attach bolts. Actually, they aren't full-sized yet--reamed to 3/8" for initial matching to the fuselage, they will eventually be drilled and reamed to 1/2" when we put the whole airplane together. By the way --you're only seeing half of the spar closest to the camera!

This was all done flat on the workbench--but then we had to attach some alignment brackets that help set the wings in exactly the right position when they are slid into the fuselage, and to drill those, we had to have access to both the front and rear of the spar, so we had to mount it vertically. At first, I figured we'd clamp one side level to the workbench, and the other would then angle up in to the air. A clever neighbor suggested that it would be a lot easier to stabilize if we mounted it upside down - so that is why the dihedral "V" is pointed the way it is--the point that will be the center of the fuselage is towards the ceiling.  And yes, those are cheap stamped shelf brackets screwed to the workbench temporarily to hold it vertical. Cheap, easy to find, and they work well.

Next --time to take it all apart and find a place to store those massive spars while we work on a huge number of wing ribs.

Paul Dye

Paul Dye, Kitplanes® Editor in Chief, retired as a Lead Flight Director for NASA’s Human Space Flight program, with 40 years of aerospace experience on everything from Cubs to the space shuttle. An avid homebuilder, he began flying and working on airplanes as a teen, and has experience with a wide range of construction techniques and materials. He flies an RV-8 that he built, an RV-3 that he built with his pilot wife, as well as a Dream Tundra they completed. Currently, they are building a Xenos motorglider. A commercially licensed pilot, he has logged over 5000 hours in many different types of aircraft and is an A&P, EAA Tech Counselor, and Flight Advisor, as well as a member of the Homebuilder’s Council. He consults and collaborates in aerospace operations and flight-testing projects across the country.

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