| 摘要 |
<p>A fan blade 110 for a gas turbine engine has an aerofoil part 12 and a root part 14. The root part 14 includes a root former 18; the root former 18 includes a zone of weakness 66 which reduces the ability of the root part 14 to withstand an impact force. Thus, in an impact situation in which the fan blade 110 has separated from the fan rotor and the fan blade 110 has itself separated into fragments, the root part 14 will fracture or buckle more easily than would be the case with conventional arrangements. This will lower the impact force of the root part 14 upon the fan casing, thus permitting the fan casing to be designed to withstand lower impact forces. The fan casing can therefore be made lighter, and cheaper, than in conventional arrangements.</p> |
