Gas turbine engine

Abstract

A gas turbine engine that includes a fan blade having a tip, a root, a pressure side, a suction side, a trailing edge and a leading edge, the fan blade including a laminate body defined by a plurality of plies comprising reinforcement fibres, wherein an angle of the fibres in the plies from the trailing edge to the leading edge at the suction side and/or the pressure side of the blade are arranged such that the laminate body is unbalanced so that, during rotation of the fan blade, the fan blade deforms such that a centre of mass of the blade rotates about a centre of rotation of the fan so as to move the centre of mass towards a balanced position.

1 . A composite airfoil, comprising:
 a first ply having a first plurality of strips of fiber oriented at a first angle with respect to a longitudinal axis and a second plurality of strips of fiber oriented at a second angle with respect to the longitudinal axis.   
     
     
         2 . The composite airfoil of  claim 1 , wherein the composite airfoil includes a root region and a tip region and wherein the first ply extends along the composite airfoil from the root region to the tip region. 
     
     
         3 . The composite airfoil of  claim 2 , wherein the composite airfoil defines a spanwise direction and wherein the longitudinal axis extends substantially parallel to the spanwise direction. 
     
     
         4 . The composite airfoil of  claim 3 , wherein the first angle is about zero degrees. 
     
     
         5 . The composite airfoil of  claim 4 , wherein the second angle is about ninety degrees. 
     
     
         6 . The composite airfoil of  claim 5 , wherein the root region comprises at least a subset of the first plurality of strips of fiber. 
     
     
         7 . The composite airfoil of  claim 5 , wherein the tip region comprises at least a subset of the second plurality of strips of fiber. 
     
     
         8 . The composite airfoil of  claim 5 , wherein the tip region comprises a first subset of the first plurality of strips of fiber and a second subset of the second plurality of strips of fiber. 
     
     
         9 . The composite airfoil of  claim 5 , further comprising a second ply having a third plurality of strips of fiber oriented at the first angle and a fourth plurality of strips of fiber oriented at the second angle, the second ply stacked adjacent the first ply. 
     
     
         10 . The composite airfoil of  claim 9 , wherein the first plurality of strips of fiber includes at least one strip of fiber that is staggered a longitudinal offset from an adjacent strip of fiber in the third plurality of strips of fiber. 
     
     
         11 . The composite airfoil of  claim 10 , wherein the second plurality of strips of fiber includes at least one strip of fiber that is staggered a lateral offset from an adjacent strip of fiber in the fourth plurality of strips of fiber. 
     
     
         12 . The composite airfoil of  claim 2 , wherein the first plurality of strips of fiber comprises carbon. 
     
     
         13 . A gas turbine engine comprising
 a fan blade having a tip, a root, a pressure side, a suction side, a trailing edge and a leading edge, the fan blade comprising:
 a laminate body that includes the composite airfoil of  claim 1 , 
 wherein angles of plies in the laminate body from the trailing edge to the leading edge at the suction side and/or the pressure side of the fan blade are arranged such that the laminate body is unbalanced from the trailing edge to the leading edge so that, during rotation of the fan blade, the fan blade deforms such that a center of mass of the fan blade rotates about a center of rotation of the fan blade so as to move the center of mass towards a balanced position, and 
 wherein, when at a state of rest, the angles of fibres of the plies at the pressure side and the suction side continuously varies from the root to the tip of the fan blade.