Assertion: helicopter | /r/HasProperty | built
Facets:
value: for military operations
type: PURPOSE
value: often
type: TEMPORAL
value: in larger militaries
type: LOCATION
Source sentences:
text: In larger militaries, these helicopters are often purpose-built for military operations, but commercially available aircraft are also used.
text: The Focke-Wulf Fw 61 is the first operational helicopter that was built in 1936 but it was only in 1942 that helicopters began to be built and used.