Assertion: tank's crew | /r/HasProperty | unaware of its absence
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text: It was later determined that a bolt vent axial (BVA) seal assembly had been removed during an earlier exercise and had yet to be replaced at the time of the incident, thus allowing explosive gases to enter the turret space; the lack of a written process for removal and replacement of the seal assembly meant that the crew at the time of the incident was unaware of its absence, and it was also noted that inadequate consideration had been given during the production of the L30 gun as to whether it could be fired without the seal assembly.