SARP’s current rocket, Pacific Impulse, is a student designed and manufactured liquid bi-propellant rocket and is designed to compete in the Spaceport America Cup’s 30k SRAD Liquid/Hybrid Category. The rocket employs an oxidizer and fuel combination of nitrous oxide and ethanol, respectively. Its structures are manufactured from aluminum, fiberglass, and carbon fiber.
Due to the COVID-19 Pandemic, physical progress was halted in mid-March 2020, when the Propulsion and Structures teams were in the midst of manufacturing.
In its current state, Pacific Impulse will have a 7.83 inch outer diameter and will be 19 feet 3 inches long. It will weigh approximately 159.4 pounds wet and 124 pounds dry.
The vehicle will have a carbon fiber body, with sections, including the nose cone, made of radio-transparent fiberglass so that signals can be transmitted to and from the internal electronics. Aluminum couplers attach the nosecone to the rest of the airframes as well as the recovery bay to the propulsion system assembly.
The vehicle’s fins will be manufactured from honeycomb core sandwich panels that are co-cured with a carbon fiber body tube using an integration ply stack.
The rocket’s O-class motor will utilize an 75% ethanol/water blend as fuel, nitrous oxide as an oxidizer, and helium as an on-board pressurant to produce an average thrust of approximately 1200 pound-force.
The propellant tanks are designed as linerless carbon composite overwrapped pressure vessels (COPVs). The onboard fluid routing system was designed for the pressurant, fuel, and oxidizer to safely flow through the rocket. The pressurant and oxidizer tanks are filled using a remotely operated fill stand designed by the team.
The thrust chamber assembly is constituted of the aluminum combustion chamber, the pintle injector and its bulkhead, the phenolic thermal protection system, a rocket candy igniter, and the graphite conical nozzle.
The avionics on the rocket transmits signals to and from ground control, including valve actuation and tank pressures. Telemetry sent to ground control includes GPS location, vehicle orientation, angular velocity, acceleration, and barometric data. On board computers record data during flight to be retrieved post recovery and communicate with the plasma payload for actuation. The Avionics team is also responsible for operating the remote fill stand to load pressurant and oxidizer to the rocket while on the launch rail and when all personnel are evacuated from the launch site.
The recovery system is a dual-deployment system with a student-manufactured drogue and toroidal main parachute. The Autonomous Recovery Experimental System (ARES) will be a stand-in parawing glider with motor controllers that will be used to replace the main parachute if the project reaches technical maturity and testing verification before competition.
The payload designed during the 2019-2020 development year was a plasma actuator for the nosecone surface to induce laminar flow. Plasma is generated using a high voltage, high frequency power supply and electrode plates, which are embedded in the surface of the nose cone. An electronic diagnostic suite detects successful actuation after necessary criteria are met, and can measure changes to flow. The plasma actuator system was designed to fit within a 3U cubesat size, based on Spaceport America Cup rules.
During the 2020-2021 development year, the Payload team will be pursuing a drone payload to be deployed during rocket descent.