Amity Mission One Report

Amity Regional High School Submission Date: December 2, 2016

Amity Aviation 25 Newton Road Woodbridge, CT 06525

Table of Contents

Section Page

Executive Summary 2 Research Report 3 Introduction 3 and Weight Reduction 3 Emissions 4 Reliability and Integrity 5 Weight and Strength 5 Calculations 1 (Old and New) 6 Efficiency Justification 6 Cost Justification 7 Conclusion 7 Calculations 2 (Choice Justification) 8 Engine Requirements 8 References 10

1 Executive Summary Throughout the two month process, Amity Aviation worked diligently to design and implement a research based approach that looked at utilizing the new CFM International LEAP engines. The team approached this task in a way that ensured efficiency and depth of understanding by all persons on the team. After looking through the background information, the team began exploring the increased efficacy the LEAP engines provide over the aging generation of CFM fans for our re-engining purposes. The team agreed to utilize a four-factor matrix while assessing all components that justify switching each original CFM engine to the new CFM LEAP engines. The individual factors that contributed to our conclusion were fuel consumption, noise, emissions, and cost. Within the matrix, each of these elements were weighted based upon a research drive approach, and then tabulated to arrive at an overall score. For instance, fuel consumption was given a 40% weight, the highest out of all the factors, as its effect on the overall efficiency was determined to be significantly higher than the other factors. Since fuel consumption is a recurring cost to a company that purchases the engine, maximizing fuel consumption is one way a purchaser can limit extraneous spending. The transition to LEAP engines not only allows the to minimize its fuel costs but also allows them to pass these savings onto customers. After finalizing the matrix (which can be viewed on the [Calculations 1] page) it was concluded that CFM LEAP engines were approximately 12% more efficient (for the team’s purposes) than their CFM56 counterparts. After this preliminary phase was completed, the team needed to decide which of the CFM LEAP engines would be used to re-engine both the 737-700, which originally had two CFM International CFM56-7B engines, and the A319, which originally had two CFM International CFM56-5B engines. After performing additional calculations comparing the specifications of the three engines, and analyzing requirements of the (Calculations 2), the team decided that the LEAP 1-A engine would best fit the , and that the LEAP 1-B would best fit the -700. Calculations showed that while in terms of , each LEAP engine was certified for the Airbus 319 and the Boeing 737-700, that only the LEAP 1-B could be used for the 737 due to the size constraints of the engine and the height of the wing. For the Airbus A319, the team utilized the information that the LEAP 1-B had significantly worse thrust and bypass than the 1-A and 1-C. This was in order to rule out the potential use of the 1-B, as the other two engines were significantly better choices for the Airbus. In deciding between the 1-A and the 1-C, the team ultimately decided to re-engine the Airbus with the LEAP 1-A engine, which had a significantly higher range of thrust than the 1-C, allowing for more versatility and higher maximum takeoff weight.

2 By utilizing and pairing each of the LEAP engines to the Airbus A319 and the Boeing 737-700, Amity Aviation was able to achieve the most cost efficient and high performance solution, creating high performance for the two aircraft while saving money for the companies utilizing the newly engined aircraft. Research Plan

Introduction The CFM LEAP Engine family is a group of high-bypass , which utilize high bypass ratios in order to create significant increases in propulsion force in the engine. The LEAP engines are an advancement from the previous group of CFM engines, known as the CFM56 engines. The LEAP engines are capable of operating under much higher pressure than the CFM56 engines, resulting in much higher efficiency for the engine. Similarly, the material use to construct the engine was changed to a carbon fiber, allowing for a much larger fan and engine, while keeping the weight of the engine reasonable. This creates a much higher bypass ratio, allowing for more propulsion in the engine. The CFM LEAP family of engines is a group of three engines: LEAP 1-A, LEAP 1-B, and LEAP 1-C (Figure 1.1). Each engine is specifically designed to be new engine options for three different aircraft families. The LEAP 1-A is utilized in the Airbus A320neo, under which the Airbus A319 is included. The LEAP 1-B is utilized in the Boeing 737 MAX, which is the Boeing 737-700 equipped with the new engine option. Finally the LEAP 1-C is used in the Comac C919, a competitor to both the Boeing 737 MAX and the Airbus A320neo. Figure 1.1

Bypass Ratio and Weight Reduction A large component of the CFM engines is the the fact that they are high bypass turbofans (Figure 1.2), meaning they have a high bypass ratio, which is the ratio of low pressure air to high pressure air within the engine. In order to create a higher bypass, higher airflow or a large fan is needed. However, a

3 larger fan creates a larger engine, which in turn weighs down the aircraft significantly. The CFM LEAP engines have a high bypass ratio without dramatically increasing the weight of the engine itself. Instead, CFM combats the increased fan size by changing the material of the fan blades, from a heavy metal to carbon fiber, a material that is both light and durable enough to support the weight of the Airbus A319 and the Boeing 737-700. This allows the bypass ratio to significantly improve, becoming approximately 11:1 for the 1-A and the 1-C, and 9:1 for the 1-B. The high bypass ratio of the engines allows for greater difference in pressure between the high pressure compressed air inside the engine and the low pressure air surrounding the engine, creating more propulsion in the engine. This extra propulsion generates more thrust which, in turn, allows for increased while providing better overall efficiency for the aircraft.

Figure 1.2

Emissions One of the greatest strengths of the LEAP engine family is the extreme reduction in nitrogen oxide (NOx) emissions. Standard regulations under the CAEP/6 regulations require certain standards regarding NOx emissions to be met in order to reduce environmental pollution. The LEAP engine family is capable of reducing emissions by at least 10% compared to the CFM56 engines, and reducing emissions by 50% compared to the CAEP/6 standards, significantly reducing air pollution. This reduction in air pollution is achieved through the use of the second generation Twin-Annular, Pre-Mixing Swirling (TAPS II). TAPS II preemptively mixes a solution of air and fuel before both elements reach the combustion chamber, allowing for a much more efficient burn, and significantly less NOx emissions.

4 Reliability and Integrity According to the Bureau of Transportation Statistics (BTS), approximately 77.34% of flights are delayed, meaning they do not arrive within 15 minutes of schedule. Mechanical problems within the engine can severely delay flights, causing high costs for both airline companies, and loss of time for . However, the LEAP engine family boasts a 99.98% dispatch reliability, meaning that 99.98% of planes with the LEAP engine are predicted to leave within this 15 minute departure window. While most aircraft operators follow a standard of 98% dispatch reliability, the LEAP engine significantly increases the reliability. While other standard aircraft are projected to leave late in 200 out of 10,000 prospective flights, the LEAP engines are only projected to miss two flights. This high reliability reduces the cost of maintenance, and increases the flight time spent in the air.

Weight and Strength The CFM LEAP engines were constructed with methods new and revolutionary to the industry. Resin Transfer Molding (RTM) is a liquid closed mold process, featuring a vacuum, that is used to create 3D woven composites. The RTM method allows for the creation of more complexly shaped composites that have superior strength-to-weight ratios. The new LEAP engine family implements these 3D woven carbon composites, as produced by the RTM method, in the fan blade and case. The standard manufacturing method in the aerospace industry is the 2-D composite production. However, the LEAP engines recognize and implement the numerous benefits of 3D woven composites. These materials, having been produced in a fairly new way, are more lightweight and durable than the parts used in a standard . These materials reduce risks of malfunction, meaning there are fewer cracks, and they cost much less for producers, both in manufacturing and through the benefits reaped. In fact, it is estimated by Bally Ribbon Mills, a leader in manufacturing, that for every pound of weight reduced in the components of an aircraft, operator's save roughly $1 million in expenses. The LEAP engines are also, for the first time ever, using 3D printed parts. The fuel nozzles on the LEAP 1-B engines are being 3D printed using lightweight ceramic matrix composites (CMCs). These nozzles can now operate in extremely high temperatures since they hold high density, more hardness and superior thermal and chemical resistance. Additionally, all 3D parts, printed or created through RMT, are lightweight and increase efficiency for the aircraft. Specially, these components cause a 15% improvement in fuel efficiency. The reduced weight, and consequential increased efficiency, advantages aircrafts with the LEAP engine over any others.

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Calculations: 1 (Old and New)

Efficiency Justification Utilizing a weighted average directly comparing the old CFM56 engines with the LEAP engines, the improvement of the CFM LEAP engines compared to the CFM56 group of engines can be clearly seen. Using a matrix to pre-determinately weigh all of the significant components of the engine, the team derived how much better the utilization of the new LEAP engines was compared to the CFM56 engines.

Engine CFM LEAP 1-A CFM LEAP 1-B CFM56-7B CFM56-5B Weight

Fuel Consumption 85% 85% 100% 100% 0.4

Noise 50% 50% 100% 100% 0.2

Emissions 90% 90% 100% 100% 0.2

Cost 130% 130% 100% 100% 0.2

Total 88% 88% 100% 100% 1

Figure 2.1 It was decided that there would be four components to analyzing the effectiveness of the new engines compared to the old engines: fuel consumption, noise, emissions, and cost. Each factor was weighted differently based on what the team believed held priority in improvement. Whichever aspect was significantly more important when comparing two engines would gain a higher percentage in the weighted average. As such, the team found that the fuel consumption of the LEAP engines were improved by 15%, the NOX emissions were reduced by at least 10%, the cost of the LEAP engines (13 million) were three million dollars more expensive than the CFM56 engines (10 million), and that the noise footprint was reduced by approximately 50%. These four percentages were placed in the weighted average and compared to the CFM56 engines, which had a default value of one. The results showed that the CFM56 engines were approximately 12% worse (Figure 2.1) than the CFM LEAP family of engines.

6 Cost Justification Using the information that the new LEAP engines were 15% more fuel efficient, online information about fuel usage, average national A1 costs, and average aircraft mileage per year, the team was able to calculate the cost of fuel per year for the old engine compared to the new engine (Figure 2.2).

Aircraft Airbus A319 Boeing 737-700 Airbus A319neo Boeing 737 MAX

Fuel Burn per seat (kg/km) 3.37 3.21 2.85 2.90

Distance per year (km) 2,816,352 2,816,352 2,816,352 2,816,352

Fuel cost per kilogram ($) 1.2561 1.2561 1.2561 1.2561

Fuel cost per year ($) 11,921,778.55 11,355,759.39 10,082,216.28 10,259,097.27

Figure 2.2 Results of calculations showed that each year, the old engines would spend approximately 11-12 million dollars on jet fuel alone. However, the new engines would save more than one million dollars every year on fuel costs. Given the costs of the CFM56 and the CFM LEAP engines, 10 million dollars and 13 million dollars respectively, the increase of price in the CFM LEAP engines would be greatly outweighed by the sheer amount of money saved through decreased fuel consumption. In two to three years, the extra money spent on the engine would be earned back solely through savings in fuel consumption.

Conclusion Calculations comparing both the CFM56 group of engines and the CFM LEAP group of engines showed that CFM LEAP engines outperformed CFM56 engines in fuel consumption, noise reduction, and emissions reductions, proving that the CFM LEAP engines are in fact an improvement from the CFM56 engines. Furthermore, the cost justification proved that using the CFM LEAP engines was economically just, as simply the money saved through fuel was enough to pay of the increased engine cost of the CFM LEAP engines. As such, the CFM LEAP engines are clearly proven to be superior to the CFM56 engines, both economically and operationally.

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Calculations: 2 (Choice Justification)

Engine Requirements In order to choose an engine, there are multiple steps that must be considered when deciding between engines: Parametric Cycle Analysis, Performance Cycle Analysis, and Installation Constraints. Parametric Cycle Analysis denotes the thrust of the aircraft, and whether it is enough to generate lift for the aircraft, allowing it to take off. Performance Cycle Analysis analyzes the thrust requirements both at sea level and at high , so that the engine must be able to have enough thrust to continuously generate lift at sea level and at high altitudes. Lastly, the Installation Constraints are the various constraints that the engine must fulfill. One very important example of a constraint is the engine ground clearance.

Simply by looking at the thrust specifications of each engine (Figure 3.1), it is clear that each of the LEAP engines is able to substitute for the CFM56 engine and perform well with the aircraft. As the ranges of all three engine models overlap, it can be assumed that all three engines pass Parametric Cycle Analysis and Performance Cycle Analysis. If the CFM56 engine can pass these two steps, then the 1-A, 1-B, and 1-C must also pass these steps, as the thrust ranges are all extremely similar.

Model Thrust Range

1-A 24,500–35,000 lbf

1-B 23,000–28,000 lbf

1-C 27,980–30,000 lbf

CFM56 21,000–30,000 lbf

Figure 3.1 As all of the LEAP engines pass the first two steps in choosing an engine, that must mean that there are installation requirements that disqualify certain engines, or simply make one engine better than the other. One of the most important Installation Requirements is engine ground clearance, which denotes that the engine must be a certain height above the ground, or else debris may fly into the engine upon landing, or the engine may hit the ground upon landing.

8 Given the engine ground clearance of the Airbus A319 and the Boeing 737-700 with all of the possible engine possibilities (Figure 3.2), it becomes clear why the Boeing 737-700 can only be re engined with LEAP 1-B. If the Boeing 737-700 were to be outfitted with the 1-A or the 1-C, the engine would only be one inch from the ground. This means that during both takeoff and landing, the angle of the plane would make the engine hit the ground, potentially damaging the engine. Furthermore, debris from the ground could be sucked up into the engine, creating potential danger to passengers on the plane. Therefore, the Boeing 737-700 simply must be re-engined with the CFM LEAP 1-B engine.

Aircraft Airbus A319 Boeing 737-700

Engine Ground Clearance (CFM56) (inches) 88.16 18

Engine Ground Clearance (1-A/1-C) (inches) 71.16 1

Engine Ground Clearance (1-B) (inches) 79.76 8.4

Figure 3.2

Lastly, the team chose the CFM LEAP 1-A engine for the Airbus A319, even though the 1-C could also have been outfitted on the plane, as the engines have the same dimensions. However, the team decided to choose the CFM LEAP 1-A because of the higher range of thrust. The CFM LEAP 1-C can only exert thrust from 27,000-30,000 lbf, while the CFM 1-A can exert thrust from 24,500-35,000 lbf. This versatility and diversity in thrust makes the LEAP 1-A engine a much better choice for the Airbus A319, as the high variance in thrust makes the plane more versatile.

9 Works Cited

"A320neo with CFM LEAP-1A Engines Receives Joint EASA and FAA Airworthiness Type

Certification." Airbus. N.p., 31 May 2016. Web. 02 Dec. 2016. ​ ​ "Advanced Propulsion Systems | GE Global Research." GE Global Research. N.p., n.d. Web. 02 Dec. ​ ​ 2016.

"." Wikipedia. Wikimedia Foundation, n.d. Web. 02 Dec. 2016. ​ ​ "The Benefits of 3-D Woven Composites." Hubspot. Bally Ribbon Mills, n.d. Web. 2 Dec. 2016. ​ ​ "Boeing 737 MAX." Wikipedia. Wikimedia Foundation, n.d. Web. 02 Dec. 2016. ​ ​ "CFM International LEAP." Wikipedia. Wikimedia Foundation, n.d. Web. 02 Dec. 2016. ​ ​ @cfm_engines. "LEAP Engines – CFM International Jet Engines." CFM International. N.p., n.d. Web. ​ ​ 02 Dec. 2016.

"Comparing A320NEO and Boeing 737 MAX by Aviation Week." Comparing A320NEO and Boeing ​ 737 MAX by Aviation Week. N.p., n.d. Web. 02 Dec. 2016. ​ "Fuel Burn A320 v 737 - Leeham News and Comment." Leeham News and Comment. N.p., 03 July 2013. ​ ​ Web. 02 Dec. 2016.

"Fuel Economy in Aircraft." Wikipedia. Wikimedia Foundation, n.d. Web. 02 Dec. 2016. ​ ​ "General Thrust Equation." NASA. NASA, n.d. Web. 02 Dec. 2016. ​ ​ Haque, Aamer. "Aircraft Performance." Aircraft Engineering and Aerospace Technology 79.3 (2007): n. ​ ​ pag. Clearly Impossible. Web. 2 Dec. 2016. ​ ​ "IV. Aircraft Performance." UNIFIED PROPULSION 4. N.p., n.d. Web. 02 Dec. 2016. ​ ​ Noujeim, Emad. "What Is the Standard Formula for Calculating Thrust Force?" Quora. Quora, 12 Aug. ​ ​ 2015. Web. 2 Dec. 2016.

10 Sundaramoorthy, Thangaraj. "What Is the Minimum Thrust Needed to Takeoff?" Aircraft Design - What ​ Is the Minimum Thrust Needed to Takeoff? - Aviation Stack Exchange. N.p., 19 Jan. 2015. Web. 02 ​ Dec. 2016.

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