Project Gryphus focuses on developing ducted rockets to collect data for studying thrust augmentation and air-augmentation on rockets that use commercial solid rocket motors. Thrust augmentation is the process in which the entrainment of a secondary flow mixing with a primary exhaust jet in a duct provide a higher thrust than the primary jet firing in isolation. For ducted rockets, the secondary flow consists of air entrained by an intake, duct, or shroud installed around the rocket’s primary exhaust nozzle.

Since the project’s start in the Fall of 2017, the team has been able to design, construct, and launch its first test vehicle, Gryphus 1, six times in the Spring 2018 semester – the most launches of any ERFSEDS rocket in a single semester. The data collected from these flights showed a 10 percent increase in the vehicle’s specific impulse its best flight.

Since then the team has been able to design, build, and launch a second test vehicle, Gryphus 2. Gryphus 2 started flying in the Fall of 2018 with the intent of continuing Gryphus 1’s mission at higher velocities and studying the effects of different sized ducts. The team is also currently constructing Gryphus 3 which will fly during the Spring 2019 semester. Gryphus 3 will be used to demonstrate the possibility of thrust augmentation on a larger high-powered rocket.

Active Vehicles

Gryphus II

Airframe Diameter 1.6 in.
Length 52 in. (without duct)
77 in. (with)
Motor CTI I170 or 38mm equivalent
Altitude 3500-4000 ft
Speed Mach 0.55
Features full fiberglass airframe, custom-built fly-away rail guide, custom aluminum brackets on fins for easily attaching and removing ducts, removable canards, Raven 3 altimeter.

Gryphus III

Airframe Diameter 4.0 in.
Length 101 in.
Motor CTI K660 or 54mm equivalent
Altitude 6500 ft
Speed Mach 0.7
Features fiberglass airframe, carbon fiber-fiberglass sandwich fins, fiberglass reinforced phenolic duct, 3D printed NACA flush-body air inlets, custom threaded ring attachment system, 2 Raven 4 altimeters, T3 GPS Tracker.