January 2014

Experimenter is a magazine created by EAA for people who build airplanes. We will report on amateur-built aircraft as well as ultralights and other light aircraft.

Issue link: http://experimenter.epubxp.com/i/247918

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Page 13 of 38

LANDINGS… To see the Lil' Cub in action, watch this video. These slats are not fixed as you think at first glance. Instead, they are airoperated; they close with speed and open once the angle of attack is increased at slower speeds. definitely produce a few more ponies. We're going to be installing a custom ground cam soon from Don's Dream Machines. "We went to Kevin and Marshall Murray at Sky Dynamics Corporation, who helped design and build the exhaust system. It lets the engine breathe much better, which is essentially free horsepower and better fuel efciency." Pilots from the lower 48 states are bound to notice the plastic Log Cabin syrup bottle zip-tied to the motor mount. Frank explained, "Most Cub engines have some blow-by out the case 14 Vol.3 No.1 / January 2014 breather, and the bottle catches any slobber, which keeps the belly cleaner." Sharp-eyed observers will also notice what appears to be unused mounts for an engine cowling that isn't installed. Frank said, "We used a cowl for 200 hours, but we ran into difculty when moving the thrust line very far. Also, with all the testing we were often running without the cowl, then, due to the weight, we just decided to leave it of. It contributed nothing but weighed something, which went directly against the concept of the airplane, which is 'Make it light and make it functional.' We do our best to stick to that." For a prop, Frank is running an 80-by-30 Catto prop. (Yes, we said 30…hey, it's a short-field machine, not a boulevard cruiser.) He said they've tried several diferent props, but the Catto pulls better than the rest. A casual glance at the front of the cockpit shows the unique forward location of the instrument panel, which exposes some unusual tubing trusses. Frank explained those: "We're running a few more horsepower so we forgo weight for strength in the motor support area. Additionally, although the fuselage follows a J-3 design, we eliminated braces on the floor, and the top of the fuselage is cross-braced with the spar attach fittings on the outside, like a Super Cub, rather than inboard, like a J-3. This gives more room and visibility." Also unusual is the overhead flap handle on the left side. Frank said, "We debated whether to have flaps because of the weight; but we talked to a lot of other pilots who advised having them, so we made them part of the design. We used twine to decide the positions and leverages, but the flaps were relatively clean and simple with a stacked pair of pulleys in the rear to Photography by Brady Lane

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