Originally Posted by
ORAC
From what I have read here previously, and I think KenV will agree, Boeing put their best management and engineers on other programmes which had problems and larger orders such as the 787 and P-8, and those assigned to the KC-46 were very much the B team. The problems which then occurred, such as not designing the wiring looms to DoD specifications etc, were down to engineering screw-ups and lack of management oversight - not a struggle to implement new technology.
The final KC-46 engineering team was definitely not the A team, but still quite good. The management team on the other hand was not up to snuff. Further, the whole KC-46 program was exceedingly drawn out and convoluted. The original plan 15 (FIFTEEN!) years ago was to produce KC-767s (like the ones delivered to Italy and Japan) and lease them to USAF. That got killed to be resurrected as a mixed purchase and lease program. That got killed. The program morphed into the KC-X competition, which had 4 or 5 different proposals. Eventually that necked down to two. EADS (now Airbus) won round 1. Round 2 got killed. And Boeing won round 3. It is literally impossible to keep the same design or management team together over a 15 year period yet over that period there were lots and lots of changes by lots of different groups of engineers, including many from Douglas Aircraft in Long Beach and McDonnell in St Louis. Despite that, the engineering was quite good and coodination tight. But because of the very tough competition from EADS/Airbus, Boeing proposed a very aggressive development schedule (not to mention a very aggressive price.) with little margin.
So what caused the delay? First the aggressive schedule did not have a lot of margin for error. It was very success oriented. The first big foul up related to civil certification of a military aircraft. Wire harnesses were designed using civil requirements, but USAF insisted (properly) they should have been done to military requirements. That cost about one third of the delay. Then a real blunder was uncovered related to the design of new fuel manifolds. That cost another three months. Then during testing a vendor mis-labelled a container of test fluid contaminating and damaging the entire fuel system of the test aircraft. That added a few more months. The boom flight control system went digital (the original was analog) and included a software feature designed to replace a mechanical over pressure relief valve. It worked great during a bunch of flight tests. But it turned out the software was not quite "robust enough" under some conditions, necessitating a change back to include the mechanical relief valve. That added more months. Not to add the relief valve, that was easy. But a lot of flight testing had been done using the new configuration and going back to the old one meant redoing a bunch of that flight testing. And so it went until the program is now about a year behind schedule.
Such glitches are pretty much par for the course (A380 had huge wiring problems early in the program also.) and are usually accommodated by the dollar and schedule margin built into the program. But this program was exceptionally tight and the margin proved to be insufficient.