wrt HSE prosecution - it would be a Crown Censure, not a prosecution.
I wonder who would receive it - CAS or ACAS as the man who signs off on an RTS?
sw
This is an interesting question, that will careful assessment of the facts. Technically, you would probably have to say (without being specific) that the key failings relate to both the original design and assumptions with respect to the addition of SCP & AAR capabilities etc. I'm not sure what safety analysis procedures were in place at the time these features were originally designed (e.g any zonal/hazard analysis type reviews during PDR, CDR etc., where they independant, etc.), but this may have some bearing on what went amiss re extant policy at the time. There was also alledgedly a more recent Safety Case produced which I assume should have followed best practice - hence it could be argued that some aspects were missed during this assessment, as this should have flagged up the design flaw if it had been done rigourously. It raises a question as to whether the MoD is responsible as it had the Safety Case commissioned, or whether the supplier of the Safety Case was in some way negligent. This will be a grey area as the supplier of the Safety Case may claim to have not known about x,y,z, (e.g. SCP operation in flight), hence its not their problem. This is a difficult one as you could argue that a competent Safety Case supplier should check assumptions and facts such as these - its part of the probing remit of Safety Case compilation to ensure the evidence is there to back up assertions of safe operation. Ultimately there is the argument the MoD is always responsible in such matters, hence is not able to discharge its reponsibilities to check the quality of externally produced Safety Cases. Was the Nimrod one reviewed by a 3rd party? Was this a fundamental part of the Safety Case process that was adopted anyway? It has admitted that there must have been a failure in the safety process, but there will be interesting lessons to be learnt as to exactly how the failure happened - it may prove quite hard to identify one action where you can definately say "that person should have spotted that issue".
Bottom line is it'll depend on what is found during the investigation, and speculation without all the facts is unlikely to reveal the true picture.