Assertion: glider's pilot | /r/CapableOf | use his skill
Facets:
value: to find them
type: PURPOSE
value: without clouds
type: OTHER
value: without dust devils
type: OTHER
Source sentences:
text: Without clouds or dust devils to mark the thermals, the pilot must use his skill and luck to find them using a sensitive vertical speed indicator called a variometer that quickly indicates climbs or descents.