Sunday, April 20, 2008

Building Airplanes is Hard

Boeing recently announced another delay in the 787 program. Industry analysts looking through holes in the fence have been predicting it for a while.
Now a year behind and power has not been applied to the first airplane yet, scheduled for about 3 months ahead of first flight.

The initial timeline was pretty aggressive, by any standard. Certification was planned to be done in about half the time of the 777. The 777 was the first big airliner to be completely designed on computers - spread all over the globe. That was pretty big undertaking, and allowed a lot of issues to be discovered without building one out of plywood first. However, the construction was pretty standard for the time - in short: Aluminum. The flight control system was fly by wire (computer controlled) but they really didn't do a lot other than move the controls in a mostly conventional way (except pitch control, which did incorporate a C* law). Flight envelope protections were weak (intentionally so) and easy to override. You could still stall the airplane. There is a case to be made - and Boeing makes it - that this arrangement is desirable.

More than a decade later comes the 787 (after a flirt with "sonic cruiser" and concept ideas as 7e7). The 787 is architecturally new in many ways. Just to name a few:
  • Composite structure (and the advantages that come from a stronger non-corroding airframe)
  • More electric architecture (increasing the usage and generation of electricity many times over, and including flight controls, pressurization, anti-icing, brakes, engine start, as a start.)
  • Extensive Computer control and networking
  • Less use of bleed air (used only for engine anti-ice)
  • Enhanced aerodynamics

In addition, Boeing took on a new manufacturing scheme where a huge percentage of the airplane is outsourced to other vendors (who, in some cases, then outsourced to other vendors).

Simply put, on the 787 virtually everything is new. It's a miracle they could do it at all - but they will. How could it not take a long time to work out all the issues, find the bugs, fix the bugs, and finally get it all right? There will be hick-ups along the way - how could there not be? But what will come out of it is an amazingly comfortable airplane to fly in, a great airplane to fly, and one that has made another generational leap in efficiency in so doing.