I am just a layman here so I am not going to juggle the technical aspects - there are plenty of people here who are demonstrably eager and capable of doing that.
One major thing which is apparent to me is that much of the argument concerns whether or not the risk is ALARP.
OK, ALARP = As Low As Reasonably Practical. This interesting but pivotal phrase encompasses three subjective aspects (which may well be defined somewhere but nevertheless give space for argument), namely
- Low. What constitutes low and who decides what is low enough? OK, so this one is mitigated by the next 2.
- Reasonable. What is reasonable to one person is not necessarily reasonable to another. What is reasonable in peacetime is not necessarily reasonable during hostilities or emergencies.
- Practicable. This depends so much on resources such as parts, equipment, cash and time as to be a vague concept at best. If the government gave the project more money then better safety would be more practicable. Importantly, what is practicable in 6 months may not be practicable now.
There are too many factors in this for everybody to be able to agree on what standard constitutes ALARP at a given time so it has to come down to the chap who gets to make the call. If he says it is ALARP then it is. 6 months down the line the ALARP standard will have changed and the situation can be reassessed.
The real question has to be "is it safe"?
Is the MR2 safe? No. What is?
Is the MR2 safe
enough? Yes, and it will get safer as time and resources allow.
What we cannot do with any system is rest on our laurels - there must always be a drive to improve the safety and survivability of the systems we use. Unfortunately, that ball is in the government's court.