Assertion: helicopter's capability | /r/CapableOf | hover for extended periods of time
Facets:
value: efficiently
type: MANNER
Source sentences:
text: The capability to efficiently hover for extended periods of time is due to the helicopter's relatively long, and hence efficient rotor blades, and allows a helicopter to accomplish tasks that fixed-wing aircraft and other forms of vertical takeoff and landing aircraft could not perform at least as well until 2011.