First, there is no slope hole or silo, the auxiliary hole of construction adopts longitudinal ventilation only by jet Second, it belongs to deep buried hole, long body, little shape section.

第一辅助洞没有斜井或竖井，施工辅助洞采用全射流纵向通风。第二辅助洞埋深大，洞体长，洞形断面小。

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The fire started after a battery in the jet's auxiliary power system overheated.

BBC: Boeing Dreamliner catches fire in Boston

Richard Walsh, a Massport spokesman, said the jet's auxiliary power unit battery, which is housed in a small compartment known as the aft electrical equipment bay, exploded after crews believed the fire was extinguished.

WSJ: Japan Airlines' Jet Suffers Fire in Boston