Dorothy seems to miss the the intent of these inputs. This aircraft accident was so botched that many training facilities use this crash as the the basis for their CRM training. Aircraft accidents normaly occur after a sucession of mistakes, not just one. This accident had so many mistakes you would have to wonder if this crew grasped the complexities of flying an L1011.
I'll list the mistakes we know of:
+Crew didn't accelerate after climb out and retard one throttle to very all gears down and locked, which they were.
+Didn't verify altitude hold loss after C-Chord warning.
+Nobody watched over CWS mode of autopilot.
+Crew member rotated new light module into nose gear receptacle rotating it in error 90 degrees forcing it to jam and not make contact.
+Two cockpit members went into fwd avionics bay to verify nose gear down bars, but nobody knew that the you had to release the view lens cover.
+They didn't make a low pass over the airport for the tower to verify nos
The L1011 auto pilot did have a wailer sound with auto pilot disconnect and it was loud. However, if a pilot moved the yoke above 15 to 25 lbs breakout force (airline option)in the CMD mode, the autopilot shifted to the CWS mode (still autopilot on) and the wailer doesn't make any sound. The only time there would be a wailer would be if the bat handle was placed in the off position or it was disengaged by actuation of autopilot disconnect switch on either control wheel. If there was a altitude hold setting and the altitude changed during the yoke movement the C-Chord sound goes off. This was heard on the tape. Certainly investigators wondered why the crew didn't react to the C-Chord sound.
The L1011 autopilot was a marvelous system and was the first US aircraft to be certified for Cat 111a approaches. However, one thing that was very unusual was there were over 15 cockpit audio warning sounds and that is pretty much of an overload and may be one of the reasons pilots were insensitive t
I believe R. Schneberger has the correct analysis of the autopilot disconnect scenario. Some others added comments about the breakout forces on the yoke. In the CMD mode the breakout force in most L1011's was 25 lbs (Eastern L1011 was less as I remember). In the CWS mode the pitch force was 4 lbs. and the roll force was 3 lbs. As others have stated there was missing Cockpit Resource Management.
M. Walsh says he never blames any pilot involved in an accident. He may never have read an NTSB report!
There were many errors contributing to this crash as shown in the comments. I'd like to include a few more. When the nose wheel down light did not light, the left or right gear light module could have been put in the nose wheel light receptacle to verify gear down. However, the poor design of that light receptacle allowed an incorrect 90 degree rotation by a crew member to jam the light receptacle and the light module wouldn't go all the way in. In spite of this error a crew member went down to the forward avionics compartment to view the nose gear down bars with a little scope on the aft bulkhead. However, you have to be knowledgeable about the view lens cover release knob to see the nose gear down bars. Apparently the crew never read the manual about this fact. They were not able to verify the gear due to this error.
One last fact worth mentioning is the landing gear warning horn. When any throttle is retarded to the lower thrust range with any landing gear not down and locked w
