In my personal view I don't think this will ever be put forward to trial by the CPS. Whilst there is a lot of public pressure because there were tragic deaths and 'somebody must pay', the burden of proof has many holes in it.
To be found guilty of 'Manslaughter by gross negligence' you have to show that the defendant wilfully ignored information that might have caused another competent pilot to take a different, safer course of action. This must be proven 'beyond any reasonable doubt'.
- The pilot was correctly licenced but was not required by the authority to carry out his display revalidation on every type he was to be licensed.
- His display training mandated by the authority did not include an 'escape manoeuvre' from inverted exits at low level, nor was he required to be tested on same.
- The maintenance history of the pitot & altimetry systems was found to be incomplete with instances of unidentified controlled components found fitted.
- This airframe had a history of altimetry issues which might have affected both airspeed and altitude indications.
The way I see it there is ample 'Reasonable Doubt' in this case. There may be a lot of public pressure for a conviction but the CPS has to ask if there is any remote prospect at all of a guilty verdict.