John Kahrs

Henson's Falco
I went down to Livermore to take a look at Doug Henson's yellow Falco. It's pretty fresh. I saw him a year or two ago and it was upside down, a mess of landing gear and firewall forward stuff filling his garage. I never thought I'd see it done so fast. I visited Dan Dorr's plane a few years ago too, He's flying now. Since I've bought those tail kits, other guys had built complete airplanes. Doug was very nice, answering all my tedious questions, confirming some things, debunking others. I can say for sure that unless the seat tracks can be changed dramatically, I'll never fit in the Nustrini Canopy, even the raised Nustrini, which is what Doug has. That's fine. I like a classic. Otherwise, he's built exactly the plane I want: full gear doors, inverted header tank, IO360 engine, and the panel is perfectly updated with a Garmin GPS and autpilot that will fly IRF approaches. Livermore was pretty foggy. I didn't ask him for a ride, which was fine. I just wanted to know if that canopy was going to work.

I went back to the garage, fixed some stuff around the house, then doubled the number of leveling blocks for the elevator construction. Bought a straight edge at Home Depot (it's good enough, just extruded L angle stock). Came back and glued a stringer on the elevator leading edge. Then I took a couple hours cutting all the plywood skins for the tail section. Incredibly tedious, especially after seeing a complete airplane, it's hard to think about cruising at 170kts down to Santa Monica while doing something like that.

But I am pretty confident that I could be skinning the elevator in a week.

Haunted by levels
I put together a 16 foot long workbench a couple years ago anticipating that I'd use it to build the tail and ailerons for the Falco. It's horribly not level, so I epoxied a series of riser blocks on it and took a shot at leveling that. Not good enough, I decided. Today I brought home a solid core door from Home Depot, ripped it down the middle and butted the ends together with a biscuit joiner. After checking along the length of it with a water level, I shimmed the blocks and screwed the door slabs down on it. The water level is just clear tubing, but it's infuriatingly accurate. It's easy to see if one side is a millimeter, or even half a mil high or low across a 16 ft span. I got pretty anal about it tonight. I leveled it across the other axis as well, using something called a SmartTool digital level, which gets me to 1/10 of a degree.

I epoxied maple extensions to hang the elevator spar from, and of course the spar is slightly twisted along its length. I considered letting the spar just be what it wants to be, and allowing it to twist invisibly inside the structure of the tail, but I'm going to straighten it as a I assemble. I'm confident the hinges will still align properly.

Each day I work on it, I wonder when enough is enough. I have real doubts about my accuracy. I wonder if I jus think 'm right, and something I can't see is wrong. Or maybe my methods are flawed, I just don't know it, and the twisted Falco I end up with will be covered with trim tabs.

As it is, I have no guru, no seasoned builder to guide me. I have memories of my dad drawing layouts with a wood spline on our kitchen floor for an 18' racing sloop when I was about 10. I watched him build boats and houses quite a bit, and my affinity for woodworking and respect for tools, especially the table saw, I owe to him. I have only sporadic visits to Falco builders, never remembering the questions I wanted to ask. I just stand there gawking "Gosh mister, it sure is purdy." I have Alfred's manual, which is excellent, and I have my own conscience pushing me to reject results that aren't good enough. I don't even know who to invite over. Engineers? Machinists? EAA guys?

I read some later chapters in the manual this past weekend, and it gets worse- like drilling holes and slots in the main wing spar. Alfred Scott tries to keep it light, but it was so daunting and exhausting I just had to close it after a while. The scope of building this plane is withering to me right now as I glue my feeble little ribs to my little elevator. Putting up the wing jig will make these ramblings sound ridiculous. The idea of gluing that one fuselage frame to the main spar was terrifying. Is that all that holds the damn thing together? A cup full of Aerolite that I stir I one evening months from now?

I was at Harbor Freight this weekend getting cheap tools, and I considered buying a cross slide vise for the drill press so I could cut those slots in the spar. It was so cheap and awful I decided against it, but I would still like to mill those slots with precision.

     

 

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