dixi188
Boeing did a lot of dumb things during the 787 development, and one of the dumbest was - in order to encourage 'out of the box' thinking and solutions - they took a blank sheet of paper design outlook
without bothering to reference the many decades of "lessons learned" experience. While there are certainly gains to be made with 'out of the box thinking', they way they did it resulting in countless cases of 'what the
were they thinking?' design errors. A few well known examples: A structural design error that resulted in a last minute delay of six months in first flight - the design error was known and well understood 'trap' in composite design (the military side of Boeing knew all about it but no one on the 787 bothered to contact them). The L/R fire system hookups were not Murphy proofed - resulting in several aircraft being delivered with the systems switched. The APU Controller (APUC) was designed by a group that had minimal experience with turbine engine control systems - resulting in an APU that was horribly unreliable at EIS - and for years after.
I was involved in a design audit of the APUC about five years ago (at which time they were on the
tenth major redesign of the APUC) and I literally had a hard time believing what I was hearing. Some of the design decisions simply defied any sort of logic. Just one example - most APUs use either aircraft power
or a dedicated alternator to power the APUC. Modern turbofan FADEC systems have redundancy - a dedicated alternator normally powers the FADEC, but if the alternator fails, the FADEC will switch over to aircraft power for the remainder of the flight (not normally dispatchable that way). So the APUC design team decided to use both a dedicated alternator and aircraft power - but the way they did it didn't provide redundancy, the APUC needed
both! Loose the alternator
or aircraft power, and the APU shutdown! WTF?
Many of the managers who oversaw the 787 development then took their management technics to the KC-46 development. We all know how well the turned out...
