Assertion: vertical tail fin | /r/ObjectUse | used on russian helicopters
Facets:
value: for the first time
type: TEMPORAL
value: in russia
type: LOCATION
Source sentences:
text: Another distinctive feature of the helicopter is its single-rotor design with a multi-blade anti-torque rotor ducted into the vertical tail fin, which was used on Russian helicopters in Russia for the first time.