0
Select Articles

The Coming Single-Aisle, Narrow-body Aircraft Bonanza PUBLIC ACCESS

[+] Author Notes
Lee S. Langston

Professor Emeritus of Mechanical Engineering, University of Connecticut

Mechanical Engineering 134(04), 53-54 (Apr 01, 2012) (2 pages) doi:10.1115/1.2012-APR-9

Abstract

This article describes the lucrative market for single-aisle narrow-body (SANB) commercial aircraft for the next 20 years. The SANB market has been the most lucrative for engine manufacturers. Boeing’s 737 and Airbus’s A320 families are powered by twin 30,000 pounds-thrust engines from CFM International or from International Aero Engines number in the many thousands. Of the 19,400 airplanes now in the worldwide air transport fleet, according to Airbus, for aircraft above 100 seats, 87% of all routes flown and 78% of all seats offered are in SANB airplanes. With the single-aisle jet liner market at record levels, not surprisingly, new players want a piece of this Boeing/Airbus duopoly pie. Both Airbus and Boeing have relied extensively over the last few years on customer financing support from export credit agencies such as the U.S. Export–Import Bank. The Russian and Chinese jets are government funded. Bombardier is getting Canadian and provincial government aid to develop the CSeries.

Two trillion dollars (US) is a lot of money. That is what airplane builders are predicting as the size of the market for single-aisle, narrow-body (SANB) commercial aircraft for the next twenty years. (See the bar charts below and[1].) If we use a rule-of-thumb estimate that 25% of the two trillion represents engine costs, that puts the 20 year market for SANB aviation gas turbines at $500 billion — an average of $25 billion per year. (The total commercial aviation gas turbine market in 2010 was $21 billion[2].)

The SANB market has been the most lucrative for engine manufacturers. Boeing’s 737 and Airbus’s A320 families, powered by twin 30,000 pounds-thrust engines from CFM International or from International Aero Engines number in the many thousands. About 7000 Boeing 737’s have been delivered since its introduction in 1968, compared to about 5000 Airbus A320’s since 1988. Of the 19,400 airplanes now in the worldwide air transport fleet[1], according to Airbus [3], for aircraft above 100 seats, 87% of all routes flown and 78% of all seats offered are in SANB airplanes.

With the single-aisle jet liner market at record levels, not surprisingly, new players want a piece of this Boeing/ Airbus duopoly pie. Regional jet maker Bombardier is entering into the main line SANB market with its 110 – 130 seat CSeries. China’s COMAC has launched its own jet with its 150 seat C919. Other players include Russia’s United Aircraft that wants to stage a comeback with the 150 – 200 seat MS-21 and Japan is developing the MRJ, a passenger jet aircraft seating 70–90 passengers, manufactured by Mitsubishi Aircraft Corporation, a partnership between majority owner Mitsubishi Heavy Industries and Toyota Motor Corporation.

With this much at stake, governments are playing a prominent role in supporting their national manufacturers. Both Airbus and Boeing have relied extensively over the last few years on customer financing support from export credit agencies such as the U.S. Export-Import Bank. The Russian and Chinese jets are government funded. Bombardier is getting Canadian and provincial government aid to develop the CSeries.

In August 2008, Bombardier launched its CSeries with the Pratt & Whitney’s Pure Power geared turbofan. In December 2010, Airbus launched its A320neo (new engine option) series, expected to enter into service in 2016, featuring a choice of Pratt & Whitneys PW1100G Pure Power or CFM International’s LEAP-X engines. The neo series attracted so many airline customers with a tremendous run up in orders (1226 at the end if 2011) that Boeing, in July 2011, was forced into making a decision to offer its new version of the extremely popular 737 series, the 737 MAX with an expected entry into service in 2017 with the LEAP-X engine being the only engine offered, similar to the other 737 models. Boeing’s order book has also swelled since the launch of the 737 MAX.

All current and potential new SANB entrants have been enabled by one key factor: the arrival of new engine technology from Pratt & Whitney and CFM International.

Pratt & Whitney’s new entry is a high-bypass geared turbofan engine commonly known as the Geared Turbofan (GTF). In the research phase since the early 1990’s, the development of the GTF started in earnest in 1998, with what is known as the PW8000. This essentially was an upgrade of the existing Pratt and Whitney PW6000 that replaced the fan section with a fan hub-mounted planetary gearing system and a new single-stage fan. After several years of development the PW8000 essentially changed to the ATFI project still using the PW6000 turbo-machinery but with a new gearbox and a singlestage fan. This led to the GTF program, which was based around a newly designed core jointly developed with MTU Aero Engines of Germany. In addition to the geared turbofan, the current design includes a variable-area nozzle which offers additional economic benefits. In July 2008, the GTF was renamed the PW1000G, the first in a new line of “Pure Power” engines. The PW1000G consists of a single-stage fan, three booster stages, eight high pressure compressor stages, two high pressure turbine stages and three low pressure turbine stages. Fan diameters vary from 56 inches for the MRJ to 81 inches for the A320neo and MS-21, with a 12:1 bypass ratio. The PW1000G will be 15% more fuel efficient and markedly quieter[4] than current engines used on regional and SANB jets. At this writing, Pratt & Whitney has conducted more than 1250 hours and 2800 cycles of full engine testing of the CSeries and MRJ engines, with the PW1524G for Bombardier completing its first flight test program in September 2012 after 25 flights and 115 flight hours on the company’s 747 test bed.

CFM International’s LEAP-X engine will power ABC (Airbus, Boeing and COMAC) SANB aircraft. LEAP-X (Leading Edge Aviation Propulsion) will not have entry into service for the A320neo until 2015 and the COMAC C919 until 2016. Development work, which started in 1999, must be completed before full engine testing begins. This will be the first all-new engine to come from the GE Aviation/SNECMA 50/50 joint venture, since the 1974 start of design and development of their very successful CFM56, now at nearly 23,000 engines delivered.

The mounting pressure to squeeze every last bit of efficiency and reliability out of existing dual-spool turbofan engine design is evident in the development of CMFI’s LEAP-X. CFMI settled on the direct drive, two-stage high pressure turbine architecture and use of GE’s latest combustor technology to reduce NOx emissions to 50% of the latest regulations. LEAP-X has a bypass ratio of 12:1, compared to 5:1 for current engines. Fan sizes are increased from 63 to 68 inches on the 737MAX and from 68 to 78 inches on the A320neo and C919. The turbine inlet temperature has been raised while cooling and coating technology will keep metal temperatures similar to CFM56 conditions. LEAP-X composite fan blades will be built using a 3D woven and resin transfer molding process, allowing thinner, lighter airfoils with better aerodynamics than achieved with titanium.

Flared gas-powered vapor absorption cycle for atmospheric water harvesting: The water condenser draws moisture from the air; a secondary liquid absorbs the evaporated refrigerant; a gas-powered boiler heats the solution to release the refrigerant as high-pressure vapor. The vapor condenses, expands through a valve, and the cycle repeats.

Grahic Jump LocationFlared gas-powered vapor absorption cycle for atmospheric water harvesting: The water condenser draws moisture from the air; a secondary liquid absorbs the evaporated refrigerant; a gas-powered boiler heats the solution to release the refrigerant as high-pressure vapor. The vapor condenses, expands through a valve, and the cycle repeats.

What about SANB aircraft development, beyond the next twenty years? NASA has launched a study under the subsonic fixed wing research program seeking to identify and develop technologies that could achieve new breakthroughs in quieter and more efficient commercial aircraft that would enter service after 2025. New advances in open rotor engine technology can make airliners more fuel efficient, but still may face a noise problem. General Electric and Rolls Royce revived the open rotor concept in 2007, saying new advances could allow such a propulsion system to achieve higher fuel efficiency targets without being significantly noisier.

To learn more about this important and evolving SANB market, I invite you to attend a panel session that Dr. Aspi Wadia of GE Aviation (who contributed to this article) and I will be co-chairing at TURBO EXPO ’12 in Copenhagen on June 12, 2012. Panel members will include representatives from General Electric, Pratt & Whitney, NASA, Boeing, Airbus, Bombardier and COMAC.

References

Boeing Commercial Airplanes, 2011, “Current Market Outlook 2011-2030” and Paris Presentation, June, 2011, www.boeing.com/commercial/cmo/.
Langston Lee S., 2011, “Powering Ahead”, Mechanical Engineering Magazine, May, pp. 30-33.
Airbus, 2011, “Delivering the Future, Global Market Forecast 2011-2030”, www.airbus.com/company/market/forecast/.
Langston, Lee S., 2008, “Changing the Game”, Mechanical Engineering Magazine, May, 2008, pp. 26-30.
Copyright © 2012 by ASME
View article in PDF format.

References

Boeing Commercial Airplanes, 2011, “Current Market Outlook 2011-2030” and Paris Presentation, June, 2011, www.boeing.com/commercial/cmo/.
Langston Lee S., 2011, “Powering Ahead”, Mechanical Engineering Magazine, May, pp. 30-33.
Airbus, 2011, “Delivering the Future, Global Market Forecast 2011-2030”, www.airbus.com/company/market/forecast/.
Langston, Lee S., 2008, “Changing the Game”, Mechanical Engineering Magazine, May, 2008, pp. 26-30.

Figures

Tables

Errata

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In