Ok.. (are you paying attention Rainbow?
), I'm not a 737 driver.. nor in fact a driver of anything! - i'm a computer consultant involved with safety critical software within the aviation sector (Radar and air traffic management).
I'd firstly like to pay my respects to all those who have lost their lives in this incident and hope that the industry can learn from the mistakes and reduce the possibilty of the same incident ocurring again.
Now for my two penneth...
From the information provided (gleaned from this forum and from the statements from Boeing) and from my knowledge of designing safety critical systems - how is it possible for a flight management system to not cross check systems?
It is all very well to say that the pilots "should be flying the aircraft", but if you overload any operator with conflicting information, it is VERY easy for them to become so distracted that they forget to do their primary function - IMHO the blame sits firmly with Boeing, they should not have released a system that allows the system to effectively ignore conflicting information WITHOUT warning the crew that there may be an issue - if I were designing such a system, i'd either introduce a third RA as a control (and then treat matching RA values as valid) - or I'd prevent the crew from selecting a suspect RA for use without first informing them that it is suspect.
Automation is good.. but it is only as good as the information you provide it... "garbage in.. garbage out"