After a test is performed, HITF engineers and scientists measure target damage, record data, and analyze the test results. Damage measurements include observing perforations of shield layers, measuring crater depths and diameters, rearwall deflection, and more. Data from diagnostic tools, like high speed cameras, are studied and used to augment the analysis.

Data from test series are used to develop ballistic limit equations, which describe the ability of a particular shield to withstand hypervelocity impact. Ballistic limit equations are used in conjunction with the environment model to determine the threat to a spacecraft.

Hypervelocity impact testing of shields enables researchers to characterize the limit of particle size, density, velocity, and impact angle (and other variables), which the shield can withstand before perforation failure. This functional relationship is called a ballistic limit curve as shown here for the multi-shock shield. Projectile diameter and velocity points which lie above the curve represent penetrating impacts, whereas points below the curve are non-penetrating.

Ballistic limit curves can be generated for a variety of different parameters, including impact angle. Impact angle is the angle between the projectile velocity vector and the target leading edge normal vector. In this graphic, the ballistic limit curve is given for impact angles of 0, 45, and 60 degrees.
 

Multiple tests on a given shield are needed to develop ballistc limit equations, which describe the largest projectile a shield can stop at a given velocity.