Crack arrestor

In Materials Science and material fatigue, a rip-stop doubler is a structurally strong ring or strip of material which serves to contain stress cracking that could lead to catastrophic failure of a device.

The rip-stop doubler can be as simple as a thickened region of metal, or may be constructed of a laminated or woven material that can withstand deformation without failure.

Rip-stop doublers were used to reinforce the airplane hull of the De Havilland Comet following a series of catastrophic accidents related to structural design problems that were previously unknown.