There is nothing inherent in a engine out scenario that causes the plane to roll on it's back.
Probably a pilot but not multi-engine rated.
I thank lomapaseo for his excellent screen capture work, it really makes it easy to discuss what happened.
I concur with the majority of posters on this thread. The fans on the starboard wing are not under power.
Both props on the port wing are putting out a lot of power-you can tell from the exhaust trails diverging and from the rapid nose down yaw at the 90 degree roll point. There was no effort to chop power on the good side (no decrease in density of the smoke trail), so the guy flying was behind the aircraft mentally.
The proximate cause of the loss of control was a mis-handling of the loss of engine power on the starboard wing. The reasons for the dual engine loss of power on the starboard wing are unknown at present. It would be interesting to know when the engine failures occurred.
At least that is my personal opinion of the accident. Unfortunately, it is improbable that the accident will be fully investigated.
You may fire when ready Gridley
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