Quick Info:
Name: Sunstreaker
Dimensions: 86 in. in length and 4 in. in diameter
Mass: 5.75 kg (~12.7 lbs)
Motor: J380 – Smoky Sam
Altitude: 2909 ft. reached during final launch
Components:
Body
The launch vehicle is made of Blue Tube from Always Ready Rocketry with a diameter of 4 inches and a total length of 86 inches. There are 3 main sections: the motor section (15.5 in), the payload section (38.5 in), and the parachute section (31.5 in). Blue Tube coupler tubes attach the sections. The couplers have an outer diameter equal to that of the inner diameter of the airframe, are 4 inches long, and have 2 inches in each side. The parachute side of the airframe is secured to one end of the coupler tube using 2-56 nylon shear pins, which will break when exposed to the force of the ejection charge. The other end has the coupler tube epoxied in place.
Nose Cone
The nose cone on our launch vehicle is made out of polypropylene plastic and has an ogive form factor. It is 16.5 inches long, and 4 inches in diameter at the base. Inside of the nose cone, we have secured a centering ring with a nut in the center. This allows the nose cone to be attached to a threaded rod in the snap feature assembly, while being removable for access to the snap features. The nose cone will be resting on the airframe for the payload section during flight, preventing the snap features from being loaded during flight.
Fins
The launch vehicle’s fins are made out of G10 garolite composite. G10 has a significant flight history in high-power rockets. It is incredibly durable and will hold up to the impact of any hard landing while being rigid enough to retain the flight characteristics of the vehicle under high aerodynamic forces. The fins are trapezoidal and have a root chord of 7.25 inches, a tip chord of 4.75 inches, and a height of 4 inches. They are symmetrical about the axis perpendicular to the airframe. They are attached in a through-wall style, fitting into 4 slits in the motor section of the airframe. The fins are epoxied to the motor mount tube and also held securely by our centering ring design.
Centering Rings
Our centering rings are designed to function as both centering rings and fin securement tools. They are 0.75 inch thick plywood made out of three layers of quarter-inch plywood. Each layer was laser cut to have alignment holes for small dowels to fit through, ensuring the proper alignment. Two of the three layers were cut to have slots for the fin tabs to slide into. This ensures that all of the fins are 90 degrees to each other and provides stability for the fins during the flight by preventing motion in the axis perpendicular to the direction of motion. The centering rings also ensure proper alignment of the motor mount tube within the airframe and serve to pair the two components during the flight.
Bulkhead
Our bulkheads are laser cut out of quarter inch thick plywood. In their center they have a quarter inch eye hook secured by nuts and washers. Once the eye hooks were attached, epoxy was used to cover the attachment to prevent them from vibrating loose. The bulkheads serve as attachment points for the shock cords. The shock cords are attached to the eye hooks using quarter inch quick links.