Abstract
The Boeing 777X aircraft has revolutionized the commercial aviation industry with some big improvements to the overall structure of the aircraft, this paper evaluates the aircraft. The main innovation to the aircraft is its new foldable wing structure that allows it to have wider wings by folding the wingtips up while on the ground. The folded-up wingtips allow the aircraft to have access to smaller runways and taxiways. While the folded down wingtips allow the aircraft to generate more lift and reduce drag in the air. There are many other advancements with the aircraft, like new materials used in the structure, greater space within the cabin, and nicer amenities for the customers. The evaluation of this aircraft contributes to a deeper understanding of the innovations that are coming to the future of the aviation industry.
Boeing 777X
The Boeing 777X is a wide-body, twin engine commercial aircraft that began development in 2013, but just took its first flight in January of 2020. The Boeing Commercial Airplanes Company has improved from their previous Boeing 777 models to develop this series of 777X variants.
The Boeing 777X has implemented a new concept of foldable wingtips to allow the wings to be about twenty feet longer than previous models, which also gives more surface area. This will provide more lift and better fuel efficiency for the aircraft. In the end, the new 777X’s will have the ability to carry up to 425 passengers further, cheaper and with more amenities than any previous model. During this research paper, technical specifications will be derived from Boeing 777X when all variants’ specifications are the same. However, whenever the variants do have differing specifications, then the Boeing 777-9 variants specifications will be used (Yun, et al, 2019).
History
Boeing has been producing 777 aircraft since the 1990’s. This variant of aircraft is iconic with its long-range ability, with a wide-body for many passengers. This is the epitome of what the commercial aviation industry is looking for, because it produces efficiency. More customer flight time per dollar.
The models before the 777 was the Boeing 727 and 747, which look nothing alike. The design of the 777 was made through automation built to design and test the aircraft. The result is a sleek, efficient design that could be assembled faster and cheaper. No mock ups or models went into the 777’s design, it was completely done on and by computers.
The Boeing 777 is also iconic for its joint design with engines. The Pratt and Whitney PW4000 engines were initially used, but they were tailored to match the aircraft to produce efficiency. That didn’t stop when Boeing switched over to General Electric and their GE90 engines, which is now the GE9X for the 777X.
Why I find it Interesting.
I have always been taught not to use the first-person point of view in research papers so this is very weird to do. But, to give my person thoughts on this aircraft and to show why I am interested, I must use it. As a background, I am an Air Traffic Controller, who has dedicated my life to aviation. I have a Bachelors in Aeronautics, about to have a Masters in Space Studies with a minor in Aerospace Science.
It astonishes me that this aircraft isn’t on the news more often for how innovative it is. It has been known that aircraft have reached a limitation. They are having to create bigger engines and put more engines on aircraft to produce more thrust with smaller wings to increase the cabin size. But this aircraft created a brand-new innovative approach to it with its foldable wings. It also revolutionized the passenger experience with dimmable windows and many other accessories.
I chose this aircraft because it is the first in a new line of commercial aircraft. Boeing set a bar that other manufacturers are going to need to meet and exceed to continue being a part of this market. I believe that this is just the start of a new era in aviation. I also chose this aircraft because I believed that it would be easy to find data on and because it is easy to find exciting things about it.
Design Features/Major Components
It is obvious that the Boeing corporation has went back to the drawing board for this aircraft family with all their improvements. They have made some of the most innovative changes to this aircraft in recent years and may have changed the commercial airliner industry forever for it.
Some of the more common changes that they made are through materials that are used on the aircraft. They changed the wing material to a composite called Carbon Fiber Reinforced Polymer. This changes effects about half of the wings structure, but the main advancement is that it reduces the weight of the aircraft in total. Less weight means more efficient. There are a couple of other changes in materials that they used. One is the use of ceramic matric composites within the hot sections of the engines and aluminum lithium alloys in the fuselage. Both changes are also meant to reduce the weight of the aircraft and improving fuel efficiency as a result (Almeida, 2019).
The big innovation of the Boeing 777X is not with material though, it is with its wingtips. Boeing decided that the limitation that they were running into is that they cannot extend their wingspan out any further due to taxiway and runway widths. If they could extend it out, then it would be an obvious thing to do because it would create more surface area for increased lift and fuel efficiency. That is where they came up with their wingtips that fold up 90 degrees on the ground to reduce its wingspan by about 26 feet. That means that when in the air, the aircraft has 26 feet more wingspan, which is about 50 square feet bigger (12 percent) than the Boeing 777-300 model (Shah, et al., 2020).
There is more to this increased surface area than more lift and fuel efficiency though. With these new changes, more lift allows for a bigger cabin. Meaning that Boeing can have more passengers, but also more cabin space, leg room and bigger overhead bins, all of which are key for a top-of-the-line commercial airliner. They have also implemented a state-of-the-art dimmable window for passengers instead of the blinds. This will allow passengers to see out without the intrusiveness of the bright sun. The advancement of the foldable wing does have its face value benefits, but after looking further into it, it is obvious that the benefits are compounding (Boeing, n.d.).
Aerodynamics
The Boeing 777X is the product of years of refining through the models that came before it. This model and its variants have been designed to improve fuel efficiency for longer and cheaper flights while also ensuring less environmental impact and noise reduction. All of which are key factors when companies are bidding on planes to put in the world’s busiest airports. The high aspect ratio design on the wings allows for an increase in lift, but also a reduction in drag. This is one of the key factors in aerodynamics that allow for the desired outcome stated previously (Hassan, et al., 2019).
Another key component that Boeing took advantage of is the redesign of components with better materials. Materials like the ceramic matrix composites used in the engine and the carbon-fiber composite materials used in the fan case and blades allow for a lighter and more durable aircraft. All of this is adding to the weight of the aircraft, which requires less lift and makes the aircraft more efficient (Boeing, n.d.).
Wings
The wings are arguably the biggest upgrade to the Boeing 777 family in the 777X and there is a lot of detail that goes into it. First, the facts, the wingspan is about 72 meters, the surface area is about 427 meters squared, and the aspect ratio is about 12.14. The produced lift coefficient is around 2.1, drag coefficient is 0.04, and going through a few equations, you can find that the lift is around 510,000 lbs and the drag is around 9,700 lbs (Anderson, 2017; Boeing, n.d.).
The big upgrade to the wings comes from the ability to fold up the wing tips while on the ground. About 11 feet into the wing tips edge, there is a mechanism that allows for the wing to fold up at a 90 degree. They added this because it was impossible to add more length to the wing without making the aircraft too big for runways and taxiways at airports. Finding a way to do this, the aircraft now have about 20 feet longer wings than previous models (Boeing, n.d.).
The aircraft also took advantage of the new materials. With lightweight composites in the wings, they were able to increase lift and reduce drag simultaneously to drastically increase efficiency (Kumar & Bhatti, 2021).
Performance
The Boeing 777X is designed to have a maximum range of 8,700 nautical miles and maximum endurance of around 200 hours. This includes a cruising speed of Mach 0.84 or 250 meters per second at 35,000 feet. The aircraft has a maximum takeoff weight of 775,000 pounds, and it can carry up to 425 passengers. The Boeing 777 family has historically used General Electric engines that are tailored to the aircraft to maximize performance. The Boeing 777X is no different, in the aircraft there are two General Electric GE9X, which are the largest and most powerful commercial aircraft engines ever produced. They are designed to provide a thrust of up to 105,000 pounds (McNerney, 2019).
Engines and Propulsion
The General Electric GE9X engines used in the Boeing 777X are the largest and most powerful commercial aircraft engines that have ever been produced. They are designed to provide thrust of up to 105,000 pounds, which is what allows the aircraft to cruise at Mach 0.84 for 200 hours and 8,700 nautical miles. The GE9X engines are noted to have a 16-stage compressor, a six-stage low-pressure turbine, and a two-stage high-pressure turbine. They have a few features that make them stand out. First, the 10:1 high-bypass ratio allows the engine to reduce fuel consumption and noise by moving 10 times more air around it, instead of through it (Boeing, n.d.).
For the GE9X, it is noted that the materials used are one of its biggest upgrades. The carbon-fiber composite fan blades and fan case and the ceramic matrix composites in the turbine are lighter and more durable than the materials previously used. This makes the aircraft lighter, enhancing performance and fuel efficiency. Lastly, the GE9X has created an advanced cooling and sealing system that allows the engine to work at higher temperatures and pressures. This upgrade also contributes to the increase in efficiency while also reducing emission (General Electric, n.d.).
Stability and Control
The Boeing 777X uses a computerized fly-by-wire system as its stability and control mechanism. This system is an electrotonic computer interface that will adjust the control surfaces to match what the pilot desires. The pilots’ inputs can adjust the aircraft, but the interface continuously keeps it with the given parameters of the aircraft. Things like the specific center of gravity that ensures stable flight, must not be overshot or it would risk destabilizing the aircraft. The computer can also adjust the center of gravity to ensure it optimizes the performance and efficiency of the aircraft, while maintaining its limits. For lateral stability, the aircraft uses dihedral angled wings.
Future
Boeing has continuously produced new models of aircraft that advances the aviation industry. Just like how the Boeing 777 family of aircraft advanced in the early 1990’s from the Boeing 727 and 747 aircraft. The 777X family of aircraft have advanced the previous models of the 777s into what it is today.
The Boeing 777X will continue to play a key role in innovating the future of aviation. This aircraft has been designed with lighter and more durable materials to lighten the weight. It has also been able to revolutionize the wing structure of its aircraft to give it more surface area but maintain the same length while on the ground. This solved the problems that were faced by commercial aviation of having too big of a plane for some runways and taxiways. Now aircraft can access all these locations while still growing its lift and reducing its drag. These aircraft are a no brainer choice for commercial aviation companies around the world (Sriwannawit & Harjani, 2021).
Conclusion
The Boeing 777X is expected to play a key role in the future of the aviation industry. It is designed to be more fuel-efficient and environmentally friendly than previous generations of aircraft. The 777X is also equipped with advanced technologies such as a new folding wingtip design, which allows it to operate at airports with smaller runways. The aircraft is expected to continue to be a popular choice for airlines around the world, as it offers a combination of range, efficiency, and passenger comfort. However, the COVID-19 pandemic has significantly impacted the aviation industry, and it remains to be seen how this will affect the demand for new aircraft such as the 777X. Nevertheless, Boeing remains committed to the success of the program and is actively working to address any challenges that may arise. Overall, the Boeing 777X is an impressive aircraft that represents the latest advancements in aviation technology, and it is sure to make a significant contribution to the industry in the years to come.
References
Almeida, R. (2019). Boeing 777X: the future of air travel. Aeronautics and Aerospace Open Access Journal, 3(2), 63-68.
Anderson, J. D. (2017). Fundamentals of aerodynamics. McGraw-Hill Education.
Anderson, J. D. (2016). Introduction to flight (8th ed.). McGraw Hill Education.
Boeing. (n.d.). 777X. https://www.boeing.com/commercial/777x/
General Electric. (n.d.). GE9X engine. https://www.geaviation.com/commercial/engines/ge9x-engine
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