I have to disagree with many of the points being made. Life is actually quite simple if you just follow a few basic rules.
The MEL is clear in as far as what constitutes a failure. The rad alt was u/s as per the mel description of a faulty system, had been detected as u/s on previous legs, but had been ignored.
The procedure is simple, enter the fault in the tech log and the CB will be collared.
The reason for doing this is that the manufacturer Boeing are/were well aware of the consequences of a failure with this system. Boeing are not responsible for informing pilots how to bypass procedures in order to keep flying.
Had that one simple action been followed we would have no discussion. This viewpoint does not detract from the discussion about unexpected anomalies following failures.
And before you all launch into attacking this viewpoint lets just go back to the Spanair accident.
Pliots are human and make genuine mistakes. It cannot be avoided. They are supposed to select flaps before take off but there is a history of forgetting. As its important a take off warning system is installed in order not to get caught when that forgetful day comes.
If you now do not handle a fault correctly that appeared over 20 times in the days/weeks preceding Madrid then forgetting to select flaps turns into a tragedy.
You can talk all you want about modern aircraft and their capabilities and weaknesses but once again the biggest single weakness here was getting around the regulations.
XL test flight not in accordance with recommendations
easyjet near accident, not entering problems in the tech log
spanair repeated fault not dealt with properly
turkish repeat fault not dealt with properly
korean 747 stansted fault not dealt with properly
you are licensed to fly and are not engineers
engineers are licensed to fix, let them do it at the first opportunity
you never know, it may save your butt
dekker has inadvertently set back safety with this report because it ignores the true root cause (not following procedures) as mentioned in earlier posts here.