K-5 Air Coach
... that there is only a single extant example of the K-5 Air Coach aircraft?
... that there is only a single extant example of the <b id="mwrg"><a href="./Kreutzer_Air_Coach" id="mwrw" rel="mw:WikiLink" title="Kreutzer Air Coach">K-5 Air Coach</a></b> aircraft?