Various “planet friendly” initiatives have emerged in Europe over the past few years as the aerospace industry reacts to the environmental challenge, which has now moved center stage. As the aerospace world converged on Paris it seems like every topic has a green backdrop. The recent annual conference of the Royal Aeronautical Society in London provided a timely summary of the work being done, as Ian Sheppard reports.
It was at the Paris Air Show in 2001 that the so-called “Group of Personalities” from Europe’s aerospace industry launched ACARE (the Advisory Council for Aeronautics Research in Europe). ACARE set a strategic research agenda to give a roadmap for aeronautical technology developments, and has led to the establishment of two very large initiatives for air traffic management research: Clean Sky and SESAR.
Europe’s aerospace industry set itself tough targets for environmental improvement following the establishment of ACARE. Broadly, these were to achieve, by 2020, a 50-percent cut in carbon dioxide (CO2) emissions, a 50-percent decrease in aircraft noise and an 80-percent decrease in nitrous oxide (NOx) emissions.
Speaking at the Royal Aeronautical Society’s annual conference in London recently, Dr. Ray Kingcombe, the UK’s ACARE representative, said that the November 2008 addendum to the latest version of ACARE’s strategic research agenda (SRA2) “addressed the need to extend the vision of Vision 2020 to 2030 and beyond, as well as changes in five areas.” He listed these areas as market design and business models; the higher profile of aviation’s contribution to emissions; security; international collaboration; and alternative fuels.
The addendum served as “a stepping stone to a ‘New Vision of Air Transport’ stretching well beyond the 2020 horizon,” said ACARE. It is a milestone in the roadmap which will culminate in the third edition of the SRA in early 2012, following a “thorough reconsideration of the challenges facing aviation,” which will take place during 2010.
The recommendations were broad and included a focus on key aerospace research facilities, ATM aspects of personal jets and “well-to-wake analysis of alternative fuels.” The ACARE goals progress evaluation (AGAPE) was launched in October 2008 and is due to report by the end of this year.
CleanSky, one of the so-called joint technology initiatives (JTIs), is a relatively new funding initiative from the European Commission, commanding a budget of ?1.6 billion ($2.2 billion) over seven years from July 1, 2008. CleanSky is broken down into six integrated technology demonstrator projects: green regional aircraft, the smart fixed-wing aircraft (SFWA), green rotorcraft, sustainable and green engines, systems for green operations and eco-design (for aircraft lifecycles). Through the ?31 million ($42 million) CleanSky technology evaluator project, each of the six technology demonstrator projects is fed into a technology evaluator to assess its impact on the global air transport system.
Paul Phillips, concept leader with Airbus UK, said that of late April, frustrating internal EC delays were inhibiting CleanSky, with industry expecting a “call for proposals” once the causes for these delays have been resolved. Phillips also gave an update on SFWA, a ?393 million ($530 million) program covering higher speed, longer range applications such as replacement Airbus aircraft and business jets.
Phillips explained that SFWA would be broken into three main projects: SFWA-1, which will look at smart wing technology (such as passive and active flow control) led by Dassault; SFWA-2, which will study new configurations (led by Saab) and SFWA-3, for flight demonstrations (led by Airbus).
“We looked at a UAV [unmanned aerial vehicle] for testing wing concepts, and at an Alphajet since Qinetiq has some [at Boscombe Down], and at the A340 flight test aircraft,” said Philipps. “We have downselected the A340 as the preferred aircraft for high speed and have done a feasibility study, which showed that we can achieve the flight conditions that we need, with high Reynolds numbers.”
The low-speed test bed is due to be selected in 2010, with the choice being between an Airbus A320 and a Dassault Falcon business jet (Dassault is a major partner in the project). An engine flying test bed will also be selected. “We are doing a ground-based demonstration and looking at how we might install an open-rotor concept on the A340 [with front and rear options]. The flagship projects are innovative powerplant integration and smart wing.”
A long-term technology flight demonstrator would also be required and may use the aircraft of “a friendly airline” or one of Airbus’s Belugas, said Phillips. They will install new outer wing panels for the A340 natural laminar flow trials. They also will employ wind tunnel tests as well as a ground demonstrator to look at structural aspects. In addition they are looking at a counter-rotating open-rotor (CROR) integration A340.
“The call for proposals has been delayed for administrative reasons but we hope to see them in June and partners engaged in January 2010. An overall CleanSky schedule re-plan will be required and a taskforce has been formed to do so,” concluded Phillips.
Late last month the European Commission starting advertising for an executive director to take CleanSky forward; the closing date for applications is July 18.
The Omega Project
Also on the agenda at the conference was the Omega project. “Omega is an academic program of 40 technology projects that aim to see how the aviation system and the environment are linked,” Professor Ian Poll of Cranfield University told the RAeS audience. “It was separated from industry to avoid problems with confidentiality and awkward conclusions.”
The results of the studies (published at omega.mmu.ac.uk), which worked from first principles of aerodynamics and aircraft performance, have been well received. “Academic rigor is a powerful element in the debate. There is a lot of information around that is nonsense. Results need to be [made available] in sufficient detail so anyone can check it.”
One key study looked at the most efficient cruising altitude for commercial aircraft, and showed that it is some 10,000 feet lower than the 35,000 feet commonly used. This, said Poll, is because the wing area had historically been dictated by field performance requirements. The best wing size is far smaller with a maximum-efficiency cruise altitude of around 25,000 feet, where you can also “avoid altitudes where air is supersaturated with respect to ice.” Accordingly, contrails, which Poll said have a far more significant net-negative environmental effect than previously thought, are not formed.
The Omega project also looked at how much fuel is saved on a given route for a particular aircraft type by taking weight off the aircraft. “It’s a common question,” Poll said, and several equations he produced showed how fuel-burn sensitivity to various factors can be calculated.
Topics that can be addressed include the penalty incurred by an ATC diversion, and the sensitivity/cost of “tankering” (carrying excess fuel from places where it can be obtained more cheaply). The Omega analysis also illustrated the “huge impact on efficiency of load factor and flying shorter distances,” said Poll. Load factor is a combination of cargo and passenger loads–in effect, the extent to which the available payload is utilized.
Poll also said that the value of reduced structural mass is sometimes overplayed, asking “is carbon fiber really the solution to everything? Even if you get 25 percent lighter, fuel burn per seat mile improves by only 10 percent.”
“Omega has just begun to open the lid on a range of issues,” he added. The project’s next step is to involve international universities and researchers, said Poll. “It’s the best £5 million I’ve seen spent anywhere,” he concluded.
David Batchelor, from the European Commission’s Directorate General Energy and Transport, gave an overview of the EC’s priorities in aviation: competitiveness, sustainability and efficiency. “The EC is investing heavily in the CleanSky program which is the single largest research program it has ever established, and it is in partnership with the private sector,” he reported. “With the European emission trading scheme (ETS), the legislation is now in force that will see aviation join in 2011. It is an important step toward a global framework that ICAO can take to the United Nations Framework Convention on Climate Change negotiations in Copenhagen in December.”
Batchelor said obligations on airlines would come before that, with the monitoring-phase-to-competent-authorities starting by the end of August, and monitoring in 2010 leading to the award of allowances for the start of the scheme in 2011.
“As aviation has no alternative to burning fossil fuels, it has to buy credits from other sectors… The ETS system stabilized at ?20 to ?30 per metric ton, then went down to ?10 but it is now [at the time of the conference] at ?12. The baseline is the 04-06 level, with the cap being based on 97 percent of that. With aviation, 85 percent of the allowances will be free and 15 percent auctioned, so if the sector declines then it may not have to buy net allowances from other sectors at first,” admitted Batchelor.
Responding to criticism of ICAO’s lack of progress toward a global framework proposal, he said, “ICAO has failed to deliver anything meaningful since Kyoto. Everyone is waiting to see the Obama Administration’s approach to Copenhagen, and there are signs that it will adopt a very different attitude. If ICAO fails to do something for Copenhagen, there is a danger that environmental ministers will take the decisions for it,” Batchelor warned.
On the Single European Sky, which comes under improved efficiency, Batchelor said, “SES was originally proposed in 2000 and is enormously challenging as it touches sovereignty, labor relations and so forth. The SES II proposal must match the liberalization of air transport. Aircraft are flying 50 km further on average than they need to. This is a huge waste and in the current context absolutely unacceptable.”