Everytime new technology is introduced to the world, you think, what’s next? Well in regards to aerospace we have whats next! Boeing’s 787 Dreamliner is the world’s first airplane to be composed mostly of carbon fiber, this is very exciting for us. The mid-sized, twin-engine jet airliner developed by Boeing Commercial Airplanes is comprised of 50% composite (carbon fiber), 20% aluminum, 15% titanium, 10% steel and 5% other but in terms of volume, the aircraft will be 80% composite. Each 787 contains approximately 35 tons of carbon fiber reinforced plastic which is partially to credit for it being the most fuel efficient airliner yet.
For years now, Boeing and the Federal Aviation Administration (FAA) have been working on certifying this jet as safe enough to fly with passengers. Many problems have been encountered along the way. For starters, back in 2005 a design disclosed that a crash deemed survivable by a 777, made mainly of metal, would be deadly for the 787 because of the jolt delivered from the fuselage crashing. Boeing now states that “a key design change and subsequent physical tests prove the final Dreamliner design is now as safe as a metal airplane.”
Another obstacle in ensuring safety is that running full-scale tests with jets is impractical and costly. Nowadays metal airplanes are being certified using computer simulations and smaller physical tests on parts like the wings, are validating the simulation results.
Paolo Feraboli, an assistant professor at the University of Washington School’s Automobili Lamborghini Advanced Composite Structures Laboratory, who has also been featured in a recent article we posted about the new Lamborghini diet, has been extensively involved in the 787 project.
Feraboli states,
“Unlike homogeneous metals, multi-layered composites are very difficult to simulate accurately on a computer. We don’t currently have the knowledge and the computational power to do a prediction based on purely mathematical models.”
A critique of using such an enormous amount of carbon fiber in the 787 deals with the hazard of post-crash fires. While the aluminum of a metal plane crumbles on impact, composites more often shatter. But in November of 2007, the FAA performed multiple fire tests which resulted in even more success of the composite plastics used in the 787 then metal. A huge plus is that the composite material allows for extra time for passengers to exit the aircraft, even without insulation.
“Ali Bahrami, head of the FAA’s Seattle office dealing with commercial-airplane certification, said the agency’s tests showed the carbon-fiber composite not only resisted burn-through impressively but also prevented toxic gases from penetrating inside.” Another plus!
The Vice President of the 787 Development team pointed out that the composite fuselage doesn’t break like glass, instead it tends to stick together by the fibers.
At this point, Boeing has completed all necessary tests and steps to move forward with the 787 Dreamliner. The FAA spokesperson implied that the certification is expected to come through by the fall of 2010.
Unfortunately, all of the tests and simulations will one day become real and we will finally know how the 787 reacts in a crash. As ridiculously cool as the 787 Dreamliner by Boeing sounds and looks, I don’t think you’ll find me on the trial run!
[Source: Seattle Times, Pictures from Boeing]