<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31449672</termId><termName>helicopters</termName><termType>PT</termType><termNote><![CDATA[ Refers to various heavier than air aircraft characterized by large-diameter, powered, horizontally rotating wings or blades that can lift the craft vertically and sustain their position in the air. ]]></termNote><termCreatedDate>2026-03-30 21:01:05</termCreatedDate><relation><relationType>UF</relationType><termId>31449673</termId><termName>helicopter</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31449674</termId><termName>whirlybirds</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31426102</termId><termName>rotary-wing aircraft</termName><termType>PT</termType></relation></term>  </Zthes>