ents. Consequently, like airframe icing, variations in flap and aileron rigging could have caused the airplane to buffet at a greater airspeed than expected. The Safety Board was unable to determine the extent to which these possible conditions individually contributed to the early onset of buffet, but concludes that some combination of airframe icing, flight control rigging, or other factors resulted in the greater-than-expected buffet onset speed. No other data related to these items leads to any other conclusions.7. The pilot not flying, as the pilot-in-command, failed to recognize, address and correct the pilot flyings inappropriate control inputs.Both pilots were qualified to act as a DC-8 captain at ABX. CVR recordings and flight crew experience indicated the pilot not flying (PNF) the airplane was acting as the pilot-in-command (PIC). During the attempted stall recovery, there were several indications of the pilot flyings (PF) excessive aft control column inputs that should have suggested to the PNF that, as the PIC, he needed to correct the control inputs and recover from the stall. Because both pilots were captains, both were managers, and both had similar backgrounds at ABX, it may be difficult for one captain to challenge the actions of the other because of a lack of overt command authority. The PNF acted more as an instructor giving mild, informal verbal instructions while trying to talk the PF into inputting the proper control inputs to recover the airplane rather than taking over the controls himself. This "teaching" continued until the aircraft impacted the ground. This finding was listed as causal and I fully agree.9. The inoperative stall warning system failed to reinforce to the flightcrew the indications that the airplane was in a full stall during the recovery attempt.The stall warning system stick shaker failed to activate during the accident sequence at the appropriate margin above the stall and during th...
