ArmorSim outputs seven penetration events per solve: ballistic limit, residual velocity, ricochet, fragmentation, plug ejection, spall, and petalling. Ballistic limit is the velocity at which the penetrator is expected to perforate; residual velocity is what remains after the plate; ricochet means the round deflected; fragmentation means the plate broke apart; plug ejection means a disc-shaped piece of plate exited; spall means small fragments flew off the back face; petalling describes the plate bending outward.
Ballistic limit
Ballistic limit is the velocity at which the penetrator is expected to perforate the plate. A round below the ballistic limit is expected to stop; a round above it is expected to perforate. The exact value depends on plate thickness, angle, material, and penetrator geometry.
Residual velocity
Residual velocity is the velocity remaining in the penetrator after the plate. NORMAL uses the Recht–Ipson residual-velocity model to estimate this value. Residual velocity is the standard way to compare two configurations against each other.
Ricochet
Ricochet means the round deflected off the plate rather than penetrating. NORMAL uses the Rosenberg ricochet model to predict whether the geometry will ricochet. Steeper angles and harder materials increase ricochet probability.
Fragmentation
Fragmentation means the plate broke apart into discrete pieces during the penetration event. NORMAL uses the Grady fragmentation model. The fragmentation output is qualitative — it tells you the plate broke, not how many fragments flew off.
Output glossary
| Term | Meaning |
|---|---|
| Ballistic limit | Velocity at which perforation is expected. |
| Residual velocity | Velocity remaining in the penetrator after the plate. |
| Ricochet | Round deflected off the plate. |
| Fragmentation | Plate broke apart during the event. |
| Plug ejection | Disc-shaped piece of plate exited. |
| Spall | Small fragments flew off the back face. |
| Petalling | Plate bent outward. |
Slow-motion playback
Every output is paired with a slow-motion viewer that plays the penetration event with a free orbit camera. Use the viewer to confirm what the numbers say — for example, a high residual velocity should match a clean perforation in the visual playback.
FAQ
What are the seven ArmorSim penetration outputs?
Each solve outputs ballistic limit, residual velocity, ricochet, fragmentation, plug ejection, spall, and petalling. Together they describe whether the penetrator perforated and how the plate responded.
What does ricochet mean in ArmorSim?
Ricochet means the round deflected off the plate rather than penetrating. NORMAL uses the Rosenberg ricochet model to predict deflection; steeper angles and harder materials increase ricochet probability.
What does spall mean in ArmorSim?
Spall means small fragments flew off the back face of the plate during the penetration event. It is one of the seven outputs and is useful for evaluating behind-armor hazards.