Landing Gear Design Part 3: Revisions
Now that we have decided on our final landing gear layout and specs, it's time to CAD it all up! We started out by modeling the triangular legs of the main gear with aerodynamic tubing. This will cost more but will ultimately reduce drag quite a bit. The aerodynamic tubing is gusseted to two main structural points on our fuselage (note how the fore tube is perpendicular to the ground and cabin longerons), and then gusseted together at the bottom. This bottom gusset is where all the magic happens. The bottom gusset connects the main landing gear aerodynamic tubing in a triangular form, so as to best distribute the plane’s weight among different joints in our fuselage. It also connects to a horizontal beam (pictured in light blue). This beam, not to be confused with the orange axle support beam, securely fastens both sides of the landing gear to each other so they don’t spread apart and create unnecessary torsional forces where they attach to the fuselage during rough landings. The lower gusset also has a pill-shaped slot cut out of it giving the orange axle support beam 4” of vertical travel. Side-to-side movement is rendered impossible by two bolted fasteners, one on each side of the gusset. These fasteners are made of Delrin®, a durable plastic with a very low friction coefficient, ensuring smooth suspension travel. The Black Max wheel and brake assemblies have integrated bearings so the axle support beam doesn’t need to rotate. Finally, an aerospace grade bungee (not modeled below) will be wrapped around both sides of the axle tube and around the bottom of the gusset. This will create a suspension system that will hold the axle tube as low as possible until a large enough force is applied (on landing) and the axle tube will be allowed to raise and lower to provide suspension and cushion on landing. The light blue C channel attached to the bottom of the lower gusset protects the bungees from any sharp edges of the lower gusset. The main wheels, braking, tail wheel, and potential bungee will be modeled in a future blog, so stay tuned!
*Editors' note: the thought processes and design choices presented in this article don't necessarily represent those implemented into the final design and are subject to change. Flight Club Aerospace is a group of amateur students with no formal education in any fields of engineering. We present this information for educational purposes only, with the understanding that it is not to be re-created without adequate professional oversight and mentorship. For our latest designs and updates, please see our most recent blog posts.