[RobRich]

Upon a crack occurring in the wing surface, an epoxy resin held in underlying embedded packs "bleeds" into the fissure to "heal" the damage and help restore structural integrity. Going a step further, dye can be inserted into the mixture to better highlight points of repaired damage.

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This simple but ingenious technique, similar to the bruising and bleeding/healing processes we see after we cut ourselves, has been developed by aerospace engineers at Bristol University, with funding from the Engineering and Physical Sciences Research Council (EPSRC). It has potential to be applied wherever fibre-reinforced polymer (FRP) composites are used. These lightweight, high-performance materials are proving increasingly popular not only in aircraft but also in car, wind turbine and even spacecraft manufacture. The new self-repair system could therefore have an impact in all these fields.

Source: Science Daily