The Right Stuff
During the last half of the 20th century and continuing in the 21st century, aeronautical engineering has made quantum leaps, with plastics playing a major role in both pragmatic improvements and dramatic advances. From aircraft and missiles to satellites and space shuttles, plastic components and products and plastic materials have been essential enablers of the most significant developments in civilian air travel, military air power and space exploration. Recall the images of the astronauts standing on the surface of the moon, looking back at earth through transparent visors built into strong helmets, and both molded of plastic – the best choice for the job.
Fast-forward to the current day and Boeing's new 787 Dreamliner, nicknamed the plastic airliner, making its maiden flight, then completing its first commercial routes in late 2011. The plane's fuselage is made of a new generation of reinforced composite plastic panels, marking a new era in commercial aircraft production. Plastic excels here for the same reasons it excels in automobiles, bicycles, and ski boots, an optimum combination of strength, design flexibility, ease of manufacturing, and yet light in weight. It is the right stuff because it is such remarkable stuff.
From Necessity to Invention
World War II accelerated the entry of plastics into aerospace as it did to all modes of transportation. More traditional materials were scarce and almost always more expensive, heavier, and harder to design and manufacture, and even more important, the possible applications of plastics were already envisioned. Vinyl materials became a major substitute for scarce rubber in airplane fuel-tank linings and fliers' boots. Virtually transparent to electromagnetic waves, the plastic used in radomes covering radar installations maximized transmission such that the material later was acknowledged as having significantly advanced the nascent radar technology.
Plastic materials can be flexible enough to withstand helicopter vibration but rigid enough to ensure safety. They can be transparent for easy observation, shatter resistant, and even offer ballistic protection. Their inherent ability to be simultaneously lightweight and strong was compelling in the 1970s, when the oil crisis compelled aerospace companies to create more fuel-efficient aircraft. The need for more efficient engines, improved aerodynamics, and less weight brought plastics to the forefront, and their usage has continued to grow. The heavier the vehicle – plane, car, truck, or spacecraft – the more fuel it needs to travel a given distance. The weight-to-fuel impact for jetliners is extreme. A one-pound weight reduction will mean tens and even hundreds of thousands of dollars in lifetime fuel savings, and plastic composites in the Boeing 787 reduced the total plane weight by about 20 percent, or thousands of pounds.
Plastics also save fuel and money because their smooth contours improve aerodynamics. And owing to their oft-referenced "combination of properties," plastics can be less expensive to manufacture, more resistant to wear, need less upkeep, and be easier to repair than other heavier materials. New uses continue to be found for plastic materials in aerospace, and new plastic materials continue to be created that further expand the range of possibilities.
Wingless Flight, too
Plastic composites are especially prevalent in today's sophisticated helicopter designs. Toughness, flexibility, and crashworthiness, combined with cost savings, have motivated large-scale use of plastics both structurally and mechanically. Helicopters vibrate a great deal, and they often carry heavy payloads of equipment and personnel. Designing one calls for materials that will compensate the vibrational stresses and be stiff enough to secure a heavy payload. Plastics do both.
Overcoming Severe Challenges
Certain plastic materials' near invisibility to radar, infrared and other spotting mechanisms make them the inevitable choice for "stealth" aircraft. The aircraft and space vehicles of the 21st century increasingly will be made of plastics. Led by the Boeing 787, commercial aircraft largely made of reinforced composite plastics are already in development. The military will continue to depend on plastics for stronger yet ever lighter aircraft that are faster, more maneuverable, and able to evade detection. And when we finally make that that great move into outer space, plastics will help us get there as well.
Using plastics in the Boeing 787 does more than save weight
Boeing used plastics extensively in its 787 Dreamliner not only for its performance but also for sound business reasons – many of them.
Even the Boeing 787's windows set new performance standards
Windows in the 787 darken from transparent to black at the touch of a button, and they are significantly larger than in any previous commercial aircraft. Passengers in the middle seats can see out, which reduces possible air sickness.