It depends on how you look at “lack of correct knowledge”. Since I’ve left the Army I’ve seen numerous problems with civvi helicopter types that, in my opinion, should have been highlighted and sorted by the manufacturer long before they became an expensive and commercially embarrassing (for the operator) problem. I’ve come to realise that manufacturers don’t admit their design mistakes in a hurry, especially if they’re not life threatening…they’ve got too much to lose in the way of money and reputation. In my mind, that’s what happened with the 4R saga you refer too….the REME were left to struggle on blindly with no guidance and the top level Brass just wanted to see results. “Don’t give me problems, just give me answers!” springs to mind…..it all gets political and scapegoats get their heads chopped to protect the big-boys.