IMPTEST involved a campaign for gas gun impact testing of shielding materials for protection of aircraft against small fragments generated by failure of rotating engine components.

The test campaign included three phases:

1. Phase 1 involved normal impact to find the ballistic limit velocity of metallic shields and three different composite shield concepts, using three different impactors at velocities below 600 m/s.
2. Phase 2 involved studies of the influence of impact angle and higher velocities etc for the two selected design concepts.
3. Phase 3 studied the influence of material aging for the selected shield concepts.

Furthermore, fibre bundle tests were performed at -40C and +120C, and the results were used in impact simulations to study the influence of temperature. High speed photography was used to record the impact response history of all specimens. In addition strain and load histories were recorded for selected specimens. The damage in all specimens was characterised quantitatively and qualitatively using various fractographic methods, e.g. C-scan.