If it does come to trial it would prob. be manslaughter. And a jury will probably convict.
I very much doubt your assumption. Where is Flying Lawyer when you need him.
There was no intent whatsoever to kill. There was no motivation to kill. The people killed were not chosen, or known to the Pilot, but were killed in a random fashion.
This was an accident. There may be some truth in the assumption that the Pilot made errors, or had not prepared sufficiently for the manoeuvres, or whatever. However even if these truths are proven beyond reasonable doubt it seems unlikely that a jury would convict because they would find there was no intent to cause injury or death.