If you survive the crash, will the 787 kill you?

Why does Boeing want to make it harder for 787 passengers to survive a plane crash?

That’s the hugely loaded question that is being asked this week by a 46-year Boeing engineer, Vince Weldon, who went public with his concerns about the 787′s crashworthiness on a Dan Rather-hosted TV special last night. Watch the show here.

Weldon believes Boeing is rushing the 787 into service before it knows for sure how the all-composite fuselage will behave in a crash landing scenario. Two key questions: Will composite structure absorb as much of the impact shock as an aluminum airframe? Does composite resist fire as well as metal?

I had my say about this issue during a live spot on the TV morning show Fox & Friends this morning, but — in case you missed it — here’s the gist of what I said.

The bottom line is that Boeing will have to prove that the 787 meets at least the crashworthiness standard of aluminum structures. If there are unknowns or validated problems, the FAA will rightly refuse to certify the aircraft.

Weldon’s real question, however, may be whether Boeing or the FAA knows enough composite structures to make a reasonable judgement.

This may be a philosophical clash more than anything else.

Weldon comes from a generation of venerated Boeing engineers who were famous for being hard-headed about safety and testing. This is a group that believed in physically validating almost any assumption.

But times have changed across the the industry. These days, more engineering assumptions are validated digitally in computer labs versus physically in flight test conditions.

I would not write Weldon off as a disgruntled employee grinding a composite ax. But nor would I write off the consensus opinion — shared by every airframe manufacturer in the business — that composites are a safer and more efficient alternative to metal.

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4 Responses to If you survive the crash, will the 787 kill you?

  1. Dan G 20 September, 2007 at 8:48 am #

    This seems odd. Carbon fibre structures are generally stronger and absorb much more energy than aluminium ones – aluminium almost “shatters”, usually along weld lines, in an impact. Further, aluminium burns fiercly – carbon fibre doesn’t burn.

    I’d *far* rather be in a composite aircraft – in fact I am, as a glider pilot – than a metal one.

  2. doc75 23 September, 2007 at 8:00 pm #

    Hasn’t the military flown aircraft largely made of composites? Wouldn’t there be some data from operating those aircraft?

  3. Stephen Trimble 23 September, 2007 at 9:17 pm #

    The B-2 is the most obvious example. Of course, we haven’t seen one crash yet.

    The army experimented with the All-Composite Aircraft Program (ACAP) in the early 1990s, and found that composite structures can be designed to be quite robust.

    NASA has had similar results with the AGATE program in the late 1990s.

    But the most most vivid examples are in the commercial world, where Burt Rutan’s Star Ship, the new generation of Very Light Jets, the 787 and the Airbus A350XWB have all embraced the all-composite fuselage. Industry seems to be voting with their feet.

  4. Max deBruyn 24 September, 2007 at 6:32 pm #

    Let’s not forget that Dan rather carries some negative baggage right now and in order to be received needs to do the shock factor referred to as the “Springer method”.
    We need to take anything that evolves from his productions with a grain of salt.
    Commercial Aircraft design is a hugely competitive industry and also one that lives under many microscopes. Further to that,the competition needs every arrow it can get for it,s quiver and untill this theory is qualified and not just a conspiracy, conspired by Airbus or EADS we need to take a long breath of objectivity.

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