In this case, I think that - in theory at least - there will be 11 inquests. (I imagine that would also apply in the US?)
I'm no lawyer, but my understanding is that inquests in the US are quite different. First of all, this falls under the jurisdiction of state governments, not the federal government, and so it varies by state. Here (Texas), if a qualified medical examiner determined the cause of death and signed the death certificate, an inquest may often not be required at all. If the cause of death was due to some unlawful action (assault, etc) or due to a legal omission (criminal negligence), then an inquest is generally required. And one inquest can cover more than one dead individual. (for example, three people who are killed in a single plane crash would result in a single inquest.) But coroners here have neither the responsibility nor the authority to make recommendations about how to prevent future such deaths. Those are policy decisions that get handled differently here.