Radial Fracture
Definition
Cracks that run outward from the point of impact like spokes on a wheel. Form first, on the side opposite the force.
- Direction
- Outward from impact point, spoke pattern
- Formation order
- First, on side opposite the force
- Related analysis
- Glass fracture direction-of-force, refractive index
Common questions
How does radial fracture pattern analysis help reconstruct a shooting?+
Angle measurements at the edge of a radial fracture, combined with the glass thickness, let an examiner estimate the approximate angle at which a projectile struck the pane, contributing to a scene trajectory reconstruction.
What is the relationship between radial fracture analysis and refractive index testing on the same glass fragment?+
They answer different questions: fracture pattern analysis addresses the direction and sequence of force, while refractive index testing compares the fragment's optical properties to a known source to establish whether they share a common origin.
Related terms
- 3R Rule
- The fracture-analysis mnemonic: Radial cracks form at Right angles to the Reverse (far, non-impact) side of the glass. Applied to the fracture...
- Concentric Fracture
- An arc-shaped fracture encircling the impact zone, produced by outer-table bending tension at a distance from the focal impact; always post-dates the...
- GRIM-3
- Glass Refractive Index Measurement, third-generation instrument by Foster + Freeman (UK); an automated phase-contrast hot-stage system that identifies the RI match point...
- Hackle Lines
- Fine secondary cracks on the fracture surface that fan from the origin, perpendicular to the moving crack front. Used to track crack...
- PDQ
- Paint Data Query database (RCMP-maintained). Cross-referenced from glass work when a vehicle is identified through paired glass and paint evidence.