 ##  [Spar](/spar) 

  ##  [Spar](https://engineering.quantumdictionary.io/spar-0) 

  
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**Engineering &amp; Applied Technologies Dictionary**

 
Definition

A principal spanwise structural member in a lifting surface (wing or rotor blade) that resists bending moments and shear forces, provides attachment points for ribs and skin/covering, and forms a principal element of the aerodynamic load path to the airframe.