Testing Capability

Testing and modeling go hand-in-hand in development of new systems. Our team is extremely competent in a diverse array of disciplines from precision machining to plumbing to electronics. This breadth of knowledge coupled with our hands-on ability enables us to perform high quality, low cost testing.

11-inch motor


3-inch motor

Rocket Motor Testing

Over the years SPG has accumulated extensive experience testing hybrid rocket motors ranging in size from 10 lbf. to over 14,000 lbf. of thrust. We do the vast majority of our own testing and facility work including all structural, plumbing, control, data-acquisition and data-reduction. Some of our accomplishments in this area include:

  • 1-inch 10-50 lbf. class GOX/paraffin-based motor
  • 3-inch 250lbf. class N2O/paraffin-based motor: Over 300 firings
  • 3-inch 250lbf. class Nytrox/paraffin-based motor: Over 20 firings
  • 11-inch 7000 lbf. class LOX/paraffin-based motor: close to 50 firings
  • Primary private contractor on NASA Peregrine Sounding Rocket ground test campaign - 14,000 lbf. class N2O/paraffin-based motor: Over 10 firings
  • 24-inch 35,000 lbf. class LOX/paraffin-based motor: We are currently engaged in engineering development for 24 inch diameter LOX/Paraffin motor testing at the 35,000 lbf. thrust level. Testing at this scale will commence during the second half of 2010.

The pictures and videos from our 3-inch and 11-inch motor firings are shown below. The picture of the Peregrine sounding rocket motor is also included.

Mechanical Properties of Fuels:

The mechanical properties of fuels are critical to the success of a hybrid or solid rocket propulsion system. SPG has developed extensive structural modeling capability. This is used to predict mechanical properties and formulate fuels for a given mission. All modeling is anchored to physical testing. We maintain facilities to do a wide array of structural property testing for research and quality control:

  • Uniaxial testing
  • Multiaxial stress testing
  • Creep testing
  • Creep rupture testing
  • Poisson's ratio testing

Fuel Processing:

We do all of our fuel grain processing in-house. Our fuel processing capability includes formulation, batch production, casting and post-processing for all of our fuels at sizes from 1-inch diameter to 36-inch diameter. We can tailor the thermochemical properties, regression rate behavior and mechanical properties of our fuels to a given mission. SPG also conducts research to explore new and improved methods of producing fuel grains.

Acoustic Testing:

SPG has a 10-inch diameter impedance tube that is used to measure the acoustic properties of various parts used in hybrid rockets.

Chemical Decomposition/Explosion Testing

SPG has substantial experience in both modeling and testing of chemical explosions, with an emphasis on nitrous oxide. Our in-house testing capabilities include a closed-volume 15,000 psia rated chemical reaction vessel useful for ignition and kinetics data (see picture to right). In addition we have done vented explosion testing for pressure-relief safety devices at tank scales up to 36-inch diameter. A picture of one such test setup can be seen to the left of the page.