As painful and expensive as it is, a full flight test program that was completed before locking in the design would have spared them all of this. A lesson learned every generation in this business. I cut my teeth in th eighties at Lockheed, and heard water-cooler tales of the C-5A program's disasterous FT program (~16 aircraft were concurrently in various stages of production, with design changes issued daily as tests showed problems....)