<a class="mw-redirect" href="https://en.wikipedia.org/wiki/Japan_Airlines_Flight_123" id="mw8Q" rel="mw:WikiLink" title="Japan Airlines Flight 123">Japan Airlines Flight 123</a> crashes into <a href="https://en.wikipedia.org/wiki/Mount_Osutaka" id="mw8g" rel="mw:WikiLink" title="Mount Osutaka">Osutaka</a> ridge in <a href="https://en.wikipedia.org/wiki/Gunma_Prefecture" id="mw8w" rel="mw:WikiLink" title="Gunma Prefecture">Gunma Prefecture</a>, Japan, killing 520, to become the worst single-plane air disaster.