Assertion: hang glider's wing | /r/HasProperty | efficient
Facets:
value: structurally
type: DEGREE
value: aerodynamically
type: DEGREE
Source sentences:
text: To be aerodynamically efficient, a wing should be straight with a long span from side to side but have a short chord (high aspect ratio).
text: But to be structurally efficient, and hence lightweight, a wing must have a short span but still enough area to provide lift (low aspect ratio).