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The Lanier Laser 200 is a fully aerobatic model of Leo Loudenslager's 1970's full-scale championship airplane. The Laser 200 kit was received as a Christmas gift and the sixth plane in the hangar. The box contained two (2) foam cores and bundle balsa sticks. The wood, which was of generally poor quality, was disappointing. Virtually every balsa stick was warped and the laser-cut lite-ply sheet was extremely flexible across the grain. Much of the balsa had to be replaced with material found locally. The fuselage sides were two (2) long 3" wide x 1/8" luaun plywood pieces, one of which was warped. The canopy was wrapped in paper, but had a wrinkle in the plastic in the visible area left from the vacuum forming process. Lanier replaced the canopy after the original was returned to them. As with other Lanier kits, no hardware was provided other than the main landing gear. The manual is very brief with no pictures or diagrams. This kit is intended for experienced builders and as such provides very little detail. The wing panels are built first and are conventional balsa-sheeted foam cores utilizing a wing tube. The cores already had the servo and wing tube holes cut, minimizing the foam cutting the builder must do. Cutting lightening holes in the foam cores was considered but ultimately they were left unmodified. The phenolic sleeve, lite-ply sleeve support plates and retaining screw inserts are epoxied to the core and the servo rails installed. The 1/2" dowel was inset for the retaining screw prior to sheeting although the recommended procedure in the instructions is to install the inserts afterwards. This made it easier to fit the dowel insert to the phenolic sleeve with no risk of damage to the sleeve from boring the sheeted wing panel. The servo mount design was changed based on previous experience. The foam slots were dug out sufficiently to inset two (2) 1/4" x 3/8" x 5" basswood sticks flush with the foam spaced properly for servo rails. The 3/32" balsa sheets were edge-glued using Titebond to form large skins and allowed to dry before sheeting the cores using Elmer's ProBond polyurethane glue. Since polyurethane glue had not been used before, experiments were done with the shucks and scrap balsa to determine the best method. Based on this experimentation, it is preferable to squeegee the glue onto the wing skins rather than applying glue to the cores. Polyurethane glue foams and penetrates while curing, so less glue is needed. It is difficult to squeegee a thin coating on the coarse surface of the foam core. Since the glue requires water to cure and the building was being done in the winter, the foam core was wiped with a damp cloth to be sure there was enough moisture for proper curing. It was also necessary to leave the cores weighed down for a least 24 hours, despite the cure time indicated on the bottle, to ensure that the glue was fully cured. After the wing cores were sheeted, the leading edge and root and tip caps are glued and sanded to shape. Filler balsa is glued to the wing root near the trailing edge to allow the wings to conform to the fuselage shape. The ailerons are cut out and trailing edges glued to the wing and leading edges glued to the aileron. After being sanded to shape, the ailerons were hinged using Robart hinge points. The fuselage was constructed to plan using the provided wood and plastic wing cover and turtledeck and ended up grossly overweight and tail heavy. The finished fuselage without engine, radio, servos and fuel tank weighed 2.5 pounds and the completed plane was 10.5 pounds. The primary source of tail weight was the luaun fuselage sides and floor and the plastic turtledeck. A second fuselage was built completely from scratch eliminating a full pound. New fuselage sides were cut from 1/8" lite-ply and lightening holes bored according to the plan. However, the first six lightening holes were expanded into 3 large ovals to save weight. The 1/4" birch firewall was replaced with three (3) pieces of lite-ply laminated together and 1.5 degrees of right thrust was installed although the plans called for 0. Additional lightening holes were bored in the fuselage floor, former F3 and in the fuselage sides under the stabilizer. The cockpit floor was cut from the plastic wing cover and more lightening holes were bored in the wing cover wood formers. The plastic turtledeck was replaced with 1/32" plywood with an added former in front of the fin to give it the proper shape. The 5/16" x 3/8" plywood servo rails were replaced with 1/4"x3/8" basswood sticks and the servos moved forward right behind the wing tube. The tail group is an open framework structure normally built from 1/4" balsa sticks, but the first set seemed very frail, so the second set was made from 3/8" balsa with very little weight penalty. For the second set, the elevators were modified slightly to provide for more rudder throw just in case it was needed. The tail group was hinged using Robart hinge points. After the stabilizer and fin were mounted, the tail blocks were fabricated from foam, sheeted with 1/16" balsa and glued to the tail group. The arrow shaft pushrods were replaced with Sullivan metal Gold-N-Rods to save weight. After the tail group was covered with MonoKote, it was braced with nylon-coated steel leader, but without the extra screws, clevises and straps called for on the plans. Two (2) long pieces of leader were crimped to a single strap on the bottom of the fuselage and laced through two (2) 1/16" holes drilled into each hard point. By looping through each hard point, a slip-proof assembly was created that required no heavy hardware. After each control surface was laced, the leader was crimped to the opposite side of the bottom strap. The provided 2 - piece plastic cowl was replaced with an after-market fiberglass unit from Stan's Fiber Tech. The fit of the fiberglass cowl was perfect and the quality excellent. The cowl was painted to match the fuselage trim pattern using LustreKote and Pactra paint and mounted using nylon bolts with O-rings under the head to prevent damage from vibration. The plastic wheel pants were discarded to eliminate weight and Dave Brown treaded 3.5" Lite Flite wheels installed. These work great and are surprisingly durable. The plane was fitted with a new YS FZ91 4-stroke engine mounted on a J'TEC Snuf-Vibe mount turning an APC 14x8 prop. The stock muffler was used as it fit reasonably well in the cowl with only a small cutout required for clearance. A Hitec Supreme FM receiver and 6V 1100mAh battery pack were installed and four Hitec HS-425BB servos were used for the elevators and ailerons and an HS-625MG servo for the rudder. A Futaba S148 servo was used for the throttle. The final version finished out at 9.5 pounds dry and needed no extra weight to balance. With the original fuselage, the plane was 10.5 pounds and tail heavy. The plans only indicate a single set of control throws, so low-rate was set a little below the recommendations and high-rate a little above. After running a gallon of fuel through the engine to break it in, the day for the maiden flight arrived and was uneventful. The plane tracked well on take-off with a little right rudder and lifted off smoothly. Only a click of right aileron was required for level flight, although even on low rates it seemed a bit sensitive. It was flown around the field and a few approaches were made to get the feel of it before finally bringing it in. On the first landing, it tip-stalled slightly but still had enough aileron authority to get it level for a bouncy landing. On subsequent flights, the plane has been brought in with more airspeed with good success. After about a dozen flights, the flight characteristics of the Laser are very impressive. The control throws were ultimately set at the designated throws for high rate except for the rudder, which is currently set at +/-2" on high rates. It tracks very well and has required virtually no trimming. It goes vertical without any tendency to fall to any side and loops without any spiraling. It rolls fast on high rates, but not completely axial and losing altitude fast while rolling. It has two (2) notably bad tendencies: a slow-speed tip stall, which should be manageable for an experienced pilot, and a high-speed snap with excessive elevator throw, which is not uncommon for aerobatic aircraft. The YS FZ91 has great power for its size, but really is insufficient for a plane with a 10 pound takeoff weight. It is able to take the Laser vertical a couple hundred feet before falling off and the speed will suffer by reducing from the 8" pitch prop to go to a 15" prop for the needed thrust. A YS FZ120 engine is being seriously considered which can be balanced by moving the battery pack further aft. While this plane has turned out to be an excellent flyer, experience with this kit has left an undesirable feeling for Lanier kits. Essentially the only parts used from the original kit in the final product were the wing foam cores, landing gear and canopy. Despite Lanier's advertising the Laser 200 as being 7.5 to 9 pounds, it is difficult to believe that this plane can be built at 7.5 pounds, much less with their supplied materials. Based on this experience, another Lanier kit will not be considered in the future. |
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