In 2005, as design of the Dreamliner advanced, a previously undisclosed Boeing analysis showed a crash that is survivable in a largely metal 777 would be deadly in a 787: The impact would shatter the bottom of the 787 fuselage and deliver a jolt severe enough to kill all the passengers.
A Boeing engineering manager called the outcome a "potential showstopper" for the Dreamliner.
Boeing says a key design change and subsequent physical tests prove the final Dreamliner design is now as safe as a metal airplane.
And while a few critics remain concerned, the Federal Aviation Administration (FAA) is close to certifying the jet as safe to fly passengers.
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A computer model by Boeing engineers in 2005 shows how the 787's fuselage would fare much worse in a crash than the fuselage of a B777
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Give me a mile of highway and I'll show you a mile; give me a mile of runway, and I'll show you the world!
Troubleshot, I believe you are miss reading the the graphic. The deceleration force in the 777 cabin would be 15G for a given simulation, for the same given conditions it would be 25G in the 787 cabin and thus fatal for the passengers.
200hr Wonder wrote:Troubleshot, I believe you are miss reading the the graphic. The deceleration force in the 777 cabin would be 15G for a given simulation, for the same given conditions it would be 25G in the 787 cabin and thus fatal for the passengers.
Ahhh ok I get it now, the composites themselves make the higher G's...thanks
At the risk of making my stupidity obvious to others, is this really relevant? How many airframes are designed to crash? Excluding the interior fittings and BRS in light airplanes, how much design compromise in the airframe is actually done towards crash-worthiness vs. weight & cost?
Designing a vehicle for crashing is probably some of the most important design work they do. It is all about how slowly you can slow the occupants inside an aircraft from the crash/incident/flying speed down to 0. The materials are designed to absorb all that energy before it gets to the passengers. In the 1940's and 50's when cars were made of solid steel and had speeds high enough to matter, deaths were quite common. The cars themselves would survive but often the occupants would not. Now it is the opposite. Cars are designed to crumple (absorb energy) and keep the passenger cabin safe. This is part of the reason why a fender bender will cause $2000 of damage to your Honda Civic where your 1950's Buick wouldn't even have a scratch. It's also why you should wear your seatbelt, otherwise all the design work in the world won't matter.
I remember an accident a few years ago in Seattle where a firetruck responding to a call collided with an armoured bank delivery vehicle. The armoured car survived almost unscathed whereas the driver and security personnel inside were tossed about and killed. And the firetruck was absolutely destroyed.
