Air travelers have a lot competing for their attention: the probing procedures of TSA employees, the lack of legroom, the fascinating pages of SkyMall. Few likely stop to consider how much the plane weighs. But because weight is perhaps the most important technical aspect of air travel, it is ever-present on the aerospace engineer’s mind. The Boeing 787 twin-engine, mid-size wide-body jetliner is the new featherweight on the block. And though critics have found fault with this newcomer to the world of air travel, the 787 incorporates revolutionary facets of design that are, I hope, here to stay.
Aircraft stay in the sky by forcing themselves against air. Their wings are designed in such a way that when this happens, the air exerts a perpendicular force back and causes the aircraft to rise. This is called lift. Intuitively, the more a plane weighs, the more lift is required. To generate more lift, planes need big engines and more fuel, which doesn’t come cheap.
Herein lies the 787’s advantage. Until now, jetliners have been made primarily of aluminum. Aluminum is historically proven to be a metal with a lot of utility, but the composites that make up more than half of the 787 are even lighter and stronger. As a result, the 787 requires less fuel, which, ideally, could mean a cheaper plane ticket.
Hans Mark, former secretary of the Air Force, professor of aerospace engineering and former deputy administrator of NASA, says, “What’s revolutionary about the 787 is that it is primarily made of composite materials.” Mark would know. He was involved in the development of the Northrop Grumman B-2 Spirit “Stealth Bomber,” a flying wing made entirely out of those materials. After the B-2’s success, Boeing knew the composites were a viable option. “Without pioneering aircraft like the B-2, the 787 would never have been built,” Mark says.
But, like all new aircraft, the 787 has its problems. Fifty 787 Dreamliners have been delivered to date, and every single one is currently grounded. Don’t take that as a necessarily bad sign, though. New aircraft require comprehensive post-production testing; that’s just how the aviation industry works. But in the 787’s case, the testing process has been somewhat complicated. Because of the new technologies employed on the aircraft, the Dreamliner is behind schedule, over budget and experiencing some interesting problems.
In a typical jetliner, the turbofan engines suck in air, compress it, mix it with fuel and explode it out the back. A lot of energy is used to compress that air, so in a standard process, some of that hot pressurized air is redirected to other uses in the aircraft, like de-icing and cabin pressurization. This is not the case with the 787. Instead, the Dreamliner uses the engines as generators to supply heavy duty lithium ion batteries which then power separate air compressors to meet the aircraft’s needs. This results in more control over the pressurized air and an engine that is 20 percent more efficient than its predecessors. That’s part of the reason the 787 has the potential to reshape air travel.
Unfortunately, this new technology may also result in fires. These new systems are having problems that were apparently hard to predict. There has been at least one fire and one account of smoke present on different 787 flights, as well as some other electrical and fuel leak problems. However, these should hardly be construed as a death sentence for the 787. Rather, they expose the dangers of inadequate testing and the price paid for it. Mark is confident that these battery problems are a “non-issue” in the long run, one he believes will be sorted out quickly. And for the consumer, it’s not cause for concern. The FAA will not allow an unsafe aircraft to fly.
Birthing pains aside, the Boeing 787 Dreamliner is the way of the future. Composite materials have proven themselves and are now ready to be integrated into commercial air travel. A few years and ironed-out kinks down the road, other commercial aircraft manufacturers will be forced to follow suit or risk extinction. Mark predicts that, with this new design, Boeing is going to “beat the world.”
Simmons is an aerospace engineering junior from Austin.