Chris Scott #924
Said "even half the possible THS of 13 NU is a frightening thought"
It has also been suggested that the PF may have inadvertently gripped the SS with his fingers gently, (more strongly than with his whole hand ?). From the threads that I have read inly a few mm of movement would cause the THS to try to compensate by increasing from the initial cruising figure of 3 or 4 NU.
PF may have concentrated on his hand flying but without his accustomed air pressure instruments - they have always been there in the past. He does not look at the THS, indeed it is something which has always "done its own thing" ( In some airlines it is a "don't touch-me " item).
PNF does not notice that all THS movements are in one direction ( the "N" means he has other duties...)
Taking CS's half the possible as 7NU, lights which came on, adjacent to the trim wheels, ONLY when this figure was exceeded. I recall that automatic fuel transfer happens around 20,000 ft. Perhaps the activation of this simple circuit might use the same figure.
In HAL BASIC " You are making me work too hard"