Some people here are too quick to suggest poor airmanship. We do not know how thorough the pre take off briefing was, but given the background of the two pilots I expect it covered the usual engine failure actions. The stiffness of the rudder could have been due to some binding or friction in the aileron circuit (interconnect on this airframe) but given the age of this old beast perhaps not unusual in itself. Whether or not the autofeather light was working should not have interfered with the system. If the system tested OK they probably considered a faulty light acceptable.
But for autofeather to work the engine must lose power with the throttle near wide open. Autofeather does not detect fire, and fire does not necessarily cause a loss of power. Cross wiring of fire warning circuits, failure of circuits to detect a fire and false warnings are not unknown. I can attest to an engine fire in which the circuit completely failed within seconds of the fire starting, leading us initially to assume a false warning.
They appear to have had a combination of control degradation tending to turn the aircraft one way and fire on the opposite side. That would take some analysis which would not be easy while simultaneously trying to maintain controlled flight in an aircraft that neither had flown extensively. Most of us would struggle with that combination on an aircraft with which we were intimately familiar. I would like to spring this nightmare scenario as an unrehearsed exercise on keyboard experts who cry "poor airmanship" or "lack of command decision making" in the simulator to see what they would do.
While the Flight Manual says the first action of the engine failure/fire drill is to feather, given the control problem it is understandable (to me at least) that they would be reluctant to do this.
Most jet pilots would probably retard the throttle on the side that they assumed was on fire, as this is a fairly universal initial procedure on jets.. Do that in a large prop driven aircraft and not only will autofeather be inhibited, but it won't fly very well, if at all.
They did the best that they could to get it on the ground and were just unlucky because of the obstacles..
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