I have witnessed a Dakota aerial top dresser fully loaded have an engine failure (port from memory) just as it cleared wheels and still take off and fly. Dumped the fertiliser down the remainder of the strip and cleared the boundary fence by about a 1m. Slow rising ground beyond the runway for about 3km resulted in the plane barely gaining any altitude but slowly it clawed it's way skyward and returned for a safe landing. I was running the airfield perimeter road when this all happened about 100m in front of me.