Captain Stable
Not quite sure what your getting at - are you saying that anyone involved in a crime that is in any way complex (aviation, fraud, company law etc. etc.) should not be tried by jury?
If we start down the road of having only 'expert' judges looking at cases, then the whole shooting match could fall into disrepute. It is a basic tenet of British Law that you are judged by your peers in open court.
As for the original point about wether flight crew should be legally responsible for their actions - of course they should, Engineers are already prosecuted if they are criminally negligent, as are all other professions.