Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-28T06:04:15.021Z Has data issue: false hasContentIssue false
  • English
  • Français

On the relationship between non-optimum operations and fuel requirement for large civil transport aircraft, with reference to environmental impact and contrail avoidance strategy

Published online by Cambridge University Press:  11 December 2018

D. I. A. Poll Open the ORCID record for D. I. A. Poll [Opens in a new window]
D. I. A. Poll*
Affiliation:
Cranfield UniversityCranfield, UK
*
d.i.a.poll@cranfield.ac.uk
Get access Rights & Permissions [Opens in a new window]

Abstract

The general problem of determining cruise fuel burn is addressed by considering the variation of the product of engine overall efficiency and airframe lift-to-drag ratio, (ηoL/D), with Mach number and lift coefficient. This quantity is the aerothermodynamic determinant of fuel burn rate. Using a small amount of real aircraft data and exploiting normalisation, it is found that near universal relationships exist between the key variables. With this major simplification, an analytic, near exact solution is derived in which the aircraft-related input data are reduced to just three parameters, namely the optimum value of (ηoL/D) and the lift coefficient and Mach number combination at which it occurs. These are quantities that are either available from open information sources or can be estimated using established analytic methods. By introducing models of the take-off and climb and the descent and landing phases, the method is extended to provide accurate trip fuel estimates.

It is shown that there is an ideal flight level (IFL) at which the fuel consumption rate is a minimum for all speeds in the normal cruise operating range. Furthermore, the IFL at the end of cruise is approximately the same for all aircraft, whilst the IFL at the beginning of cruise depends, primarily, on the distance to be flown. There is little dependence on the size of the aircraft, or its take-off mass.

In the context of the ‘fuel-based’ assessment of operational inefficiency, the method is further developed to determine the sensitivity of the trip fuel requirement to changes in the operational parameters governed by air traffic management (ATM). The result is two simple equations. These are used to estimate the current ATM fuel burden. At the global level, this is about 20% with more than half being attributable to flights of less than 1,200 km.

Finally, the method is used to estimate the fuel burn penalty associated with reducing contrail formation by simply avoiding those regions of the atmosphere that are supersaturated with respect to ice. If the aircraft is at the IFL when avoiding action is required, flying below the supersaturated region minimises the additional fuel use. Even when multiple evasive manoeuvres are needed, the additional trip fuel requirement is expected to be less than 0.5%.

Keywords

AviationFlight physicsCruise fuel consumptionCruise altitudeTrip fuelOperational inefficiencyAir traffic managementEnvironmental impactContrail avoidance
Type
Research Article
Information
The Aeronautical Journal , Volume 122 , Issue 1258 , December 2018 , pp. 1827 - 1870
Copyright
© Royal Aeronautical Society 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. IPCC Aviation and the global atmosphere. Intergovernmental Panel on Climate Change Special Report. 1999, https://www.ipcc.ch/pdf/special-reports/spm/av-en.pdf Google Scholar
2. Poll, D.I.A. 21st century civil aviation is it on course, or is it over confident and complacent? – thoughts on the conundrum of aviation and the environment, Aeronautical J, 2017, 121, (1236), pp 115–140.Google Scholar
3. Lee, D.S., et al. Aviation and global climate change in the 21st century, Atmospheric Environment, 2009, 43, pp 3520–3537.Google Scholar
4. Gierens, K. and Spichtinger, P. On the size distribution of ice-supersaturated regions in the upper troposphere and lowermost stratosphere, Annales Geophysicae, 2000, 18, pp 499–504; EGS-Springer-Verlag).Google Scholar
5. Dickson, N.C., Gierens, K., Rogers, H.L. and Jones, R.L. Vertical spatial scales of ice supersaturation and probability of ice supersaturated layers in low resolution profiles of relative humidity. TAC-2 Proceedings, 22–25 June 2009, Aachen and Maastricht, pp 239–243.Google Scholar
6. Mannstein, H., Spichtinger, P. and Gierens, K. How to avoid contrail cirrus, Transport Research D, 2005, 10, pp 421–426.Google Scholar
7. Schumann, U., Graf, K. and Mannstein, H. Potential to reduce the climate impact of aviation by flight level changes. Third AIAA Atmospheric and Space Environments Conference, AIAA-2011-3376, 2011.Google Scholar
8. Cavcar, A. Constant altitude-constant Mach number cruise range of transport aircraft with compressibility effects, J Aircraft, 2006, 43, (1), pp 125–131.Google Scholar
9. Filippone, A. Comprehensive analysis of transport aircraft flight performance, Progress in Aerospace Sci, 2008, 44, (3), pp 192–236.Google Scholar
10. Guynn, M.D. First-order altitude effects on the cruise efficiency of subsonic transport aircraft, NASA TM-2011-217173, August 2011.Google Scholar
11. Lovegren, J.A. and Hansman, R.J. Estimation of potential aircraft fuel burn reduction in cruise via speed and altitude optimization strategies. Report No. ICAT-2011-03, MIT International Centre for Air Transportation, Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, February 2011.Google Scholar
12. Shevell, R.S. Fundamentals of Flight, 2nd ed. Prentice-Hall International, UK; ISBN 0-13-332917-8, 1983.Google Scholar
13. Schaufele, R.D. The Elements of Aircraft Preliminary Design, Aries. Publications, Santa Ana, California, USA; 2007. ISBN 0-9701986-0-4.Google Scholar
14. Torenbeek, E. Advanced Aircraft Design – Conceptual Design, Analysis and Optimisation of Subsonic Civil Airplanes. John Wiley and Sons, Chichester, West Sussex, UK; 2013. ISBN 9781119969303.Google Scholar
15. ESDU Subsonic lift-dependent drag due to the trailing vortex wake for wings without camber of twist. Engineering Sciences Data Unit Item 74035, October 1974 (amended April 1996).Google Scholar
16. ESDU Approximate methods for estimation of cruise range and endurance: aeroplanes with turbo-jet and turbo-fan engines. Engineering Sciences Data Unit Item 73019, October 1973 (amended May 1982).Google Scholar
17. Airbus Getting to grips with aircraft performance. Airbus Customer Services, Toulouse, France, January 2002.Google Scholar
18. Airbus Getting to grips with the cost index. Airbus Customer Services, Toulouse, France, May 1998.Google Scholar
19. Airbus Getting to grips with fuel economy. Airbus Customer Services, Toulouse, France, October 2004.Google Scholar
20. Randle, W.E., Hall, C.A. and Vera-Morales, M. Improved range equation based on aircraft data, J Aircraft, 2011, 48, (4), pp 1291–1298.Google Scholar
21. Martinez-Val, R., Palacin, J.F. and Perez, E. The evolution of jet airliners explained through the range equation, Aerospace Engineering, Proceeding IMechE, 2008, 222, (Part G), pp 915–919.Google Scholar
22. ESDU Properties of a standard atmosphere. Engineering Sciences Data Unit Item 77021, October 1977 (amended June 1986).Google Scholar
23. Airbus A318-A319-A320-A321 Type-Certificate Data Sheet, TCDS A.064 Issue 02, European Aviation Safety Agency, June 2006.Google Scholar
24. Poll, D.I.A. A first order method for the determination of the leading mass characteristics of civil transport aircraft, Aeronautical J, 2011, 115, (1167), pp 257–272.Google Scholar
25. Reynolds, T.G. Analysis of lateral flight inefficiency in global air traffic management. 8th AIAA Aviation Technology, Integration and Operations Conference, Anchorage, Alaska, 14–19 September 2008.Google Scholar
26. 2015 Comparison of air traffic management-related operational performance: U.S./Europe. EUROCONTROL for the European Union and the Federal Aviation Administration Air Traffic Organization System Operation Services, August 2016, http://www.eurocontrol.int/publications/2015-comparison-air-traffic-management-related-operational-performance-usa-and-europe Google Scholar
27. Eyers, C., Norman, P., Plohr, M., Michot, S., Atkinson, K. and Christou, R. AERO2k global emissions inventories for 2001 and 2025. Technical Report 04/01113 QinetiQ Ltd., Farnborough, UK, 2004.Google Scholar
28. Cumpsty, N.A. and Heyes, A.L. Jet Propulsion, 3rd ed. Cambridge University Press, UK; 2015. ISBN 978-1-107-51122-4.Google Scholar