So What Is Wrong With The Dreamliner?
by Clive Irving
The Boeing 787 Dreamliner, which promised to bring travelers the future of flying as it should be in the 21st century (a lot less gas guzzled, a lot more comfort in the cabin) could be delayed reaching an airport gate near you for a lot longer than Boeing intended. Tuesday's deferment of the first flight raised more issues than it answered, the principal one being how long it will take to fix the flaw discovered in the structure.
A Q&A session between financial analysts and Boeing managers shed little light on specifics. In fact, reading the transcript, it seems that the analysts failed to ask an essential question.
Boeing prepared the first airplanes for flight testing at Everett, Washington. The first test airplane was about to begin taxiing tests. An exciting moment, because this is when the engines are powered up and the machine actually rolls under its own power for the first time. If that goes without a glitch, the taxiing tests speed up to the point of a lift-off of the nose wheel, followed by a return to earth. The next step is to fly.
Simultaneously with flight testing, what is called a static test has been going on for two years. This is where a 787, complete in all structural components, undergoes stress testing that simulates a long program of flights. It is stressed to limits well beyond any airplane would expect to encounter in reality.
It was in one of the static tests that a failure occurred recently, and that led to the deferment of the first flight.
We know what failed: an area of the outer skin where the wings meet the fuselage. According the Boeing mangers, there were 36 ruptures of the airplane's skin, 18 on each side of the fuselage. The 787 is built of composites. The parts involved were made in Japan, by two companies, Fuji and Mitsubishi. Now, working with these two companies, Boeing has to analyze the failure--understanding first what the stresses were that caused the failure--and then design and install a strengthened section on each wing and the adjoining fuselage. Just how long that will take nobody knows.
But here's the missing question: If the first test 787 had taken to the air on the original schedule, or even later, that is at some point in the last year, before that flaw showed up in the static testing, would the airplane have been endangered?
In the interview with analysts, the Boeing managers, including the CEO, Scott Carson, said that they could have flown the 787 even knowing of the flaw but--and this is a big but--within a limited flight regime, avoiding higher stresses.
That suggests, in fact, that flying a full test program without knowing of this fault might well have taken the stresses to a point when the structure would have failed. And a failure like that in flight, recoverable or not, would have been catastrophic for the future of the 787.