Fan blade with flexible airfoil wing

A fan comprising:

• a plurality of flexible fan blades connected at a root end of each of a plurality of multiple main spars that are connected to a common fan hub, each of the flexible fan blades comprising at least:
• a curved, flexible wing, having at least a lower portion, a leading edge, and an upper portion, the lower portion of the curved, flexible wing extending to the leading edge of the curved, flexible wing, the leading edge of the curved, flexible wing extending to the upper portion of the curved, flexible wing and the leading edge of the curved, flexible wing having a first radius of curvature in response to the curved, flexible wing being in a relaxed state and a second radius of curvature in response to the curved, flexible wing being in a deflected state, thereby creating a flexible airfoil of the flexible fan blade, the upper portion of the curved, flexible wing and the at least a lower portion of the curved, flexible wing forming an at least partially open channel adjacent the leading edge of the curved, flexible wing;
• and
• a main spar disposed in the at least partially open channel, the main spar having at least a lower surface and a leading edge having a second radius of curvature greater than the first radius of curvature, the lower surface of the main spar connecting to the lower portion of the curved, flexible wing and the leading edge of the main spar abutting an internal curvature of the leading edge of the curved, flexible wing.

An apparatus comprising:

• a flexible fan blade, the flexible fan blade comprising:
• a flexible wing, the flexible wing formed from a contiguous blade, the contiguous blade comprising:
• a first end;
• a second end opposite the first end;
• a first portion adjacent the first end, the first portion configured to have a first radius of curvature in response to the contiguous blade being in a relaxed state and the first portion configured to have a second radius of curvature in response to the contiguous blade being in a deflected state;
• and
• a second portion adjacent the second end, the second portion having a second radius of curvature, the second radius of curvature less than the first radius of curvature and the second end being returned and directed toward the first portion forming an at least partially enclosed channel at the second portion;
• and
• a main spar disposed within the at least partially enclosed channel at the second portion of the contiguous blade, the main spar configured to abut the second portion when the contiguous blade is under a predetermined amount of tension.