Asymmetric throttle lever control during landing risky?
Goldenrivett - thanks for posting that link, I found it to be an interesting read about a sad event that should have been preventable.
It seems to me that any procedure that calls for asymmetric control of the throttle levers during landing introduces a safety risk. In the event referenced, one lever was left commanding significant forward thrust while the other was moved to idle and then to reverse. Would it not be better to have a procedure that calls for both throttle levers being retarded to idle with reverse thrust being commanded on both throttle levers at pilot discretion provided there is not a known reverser fault?
There is mention in the report of a 55 meter landing distance penalty related to how the throttles are used during landing, but it is not clear if that would mean that longer runway is required for landing with no usage of reverse vs. landing with one of the reversers known to be inop but planning to use the other.
Having a system where moving the throttle lever to command reverser can result in increased forward thrust if the reverser fails to deploy seems to me to be a major design error. There should be interlocks such that engine spool up for increased reverser action will not happen unless the reverser has properly deployed.
I am still left with the question as to whether or not landing field length requirement determination takes credit for availability and usage of reverse thrust.