Cardinal:
As you might have read, this also happened on the Martin B-26 back in WW2 ("One a day in Tampa Bay"). Read about what IPs did to control the plane when a prop oversped right after takeoff. The short wings (+loading) required a very high Vmc.
Do SF-340 props have NTS protection? Can overspeed cause the shaft to decouple at the gearbox, as with the Allison engines?
From what I've read, at first the Curtis electric props were difficult to maintain, and the Instructor Pilots were also very new. This problem might have happened on the C-46 Commando, flying through the worst weather in the world, over the highest mountains (the "Hump")
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