08 Mar 2007
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High speed image of a projectile
A double exposure X-ray image of a 1.5 gramme tungsten cube impact at 2670 metres/second on a 1.6mm stainless steel target. First exposure (left) shows the projectile before impact and the second, 50 microseconds later, shows the debris cloud produced by the impact.
BAE Systems manufactures a range of products which, during their life, can suffer damage due to impacts. Minor damage can be repaired, but more serious damage may require replacement of significant parts of the structure and in a few instances the impact event can cause disastrous failure such as an air crash.
By conducting controlled impact experiments at our specialist impact facility, a detailed understanding of the impact process has been obtained. A range of single and two-stage gas guns are used to propel projectiles at speeds of up to 4 kilometres per second and the impacts are recorded using very high speed cameras, X-ray systems, pressure transducers and strain gauges.
The resulting data helps design engineers to create structures that are more tolerant of impact events and can absorb impact energy, thereby reducing damage. We study a wide range of impacts, from bird strike and runway/engine debris impacts and from bullets to high speed warhead fragments. Facilities have been developed over a number of years to study all these events and more, and to analyse how materials behave under the high strain rate and shock loading conditions experienced during an impact.
