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Old 26th Jun 2009, 10:51
  #2359 (permalink)  
steamchicken
 
Join Date: Mar 2002
Location: Surrey, UK
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Would you be confident in putting the control system back from its fail-safe mode into its normal mode, knowing that one of the critical data sources was untrustworthy? Note that it behaved as it was designed to, reacting to loss of data by moving from Normal Law (with lots of computerised protections that depend critically on this data) to Alternate Law (with fewer protections that don't).

After the speed indication came back on line, it was still true that it was now an unreliable data source. It seems more than sensible that, if it isn't safe to use normal with unreliable speed indication, it isn't safe to use it until the speed indication has been *proven* to be reliable again. The word unreliable doesn't mean permanently broken, it means that you can't rely on it.
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