Are you saying that boeing realise the P51 was rubbish?
no, that is not at all what I am saying, let us say that Boeing sells a "New" P-51 that is identical to a WWII fighter for, say, $1,800,000. Let us then speculate that because of a minor failure of some small part supplied by a subcontractor, that the "new" P-51 crashes into a crowded shopping mall at the height of the Christmas shopping season. Let us suppose that a hundred shoppers are killed, scores more are wounded and several stores burn down. Because Boeing did not install a ballistic parachute recovery system they are held liable for the deaths, injuries and property damages which could amount to a billion or more dollars in jury awards. That is what I mean by liability issues. it is not a reflection on the P-51 but it is the nature of the lawsuit happy society we live in that causes it.