How to green Europe’s skies

Summary

The question of how to balance aviation’s huge social and economic contribution with its impact on climate change is not a new one. Few question that aviation is a relatively small contributor of global greenhouse gases (the UK’s Stern Review on the Economics of Climate Change puts aviation CO2 emissions at 1.6% of the global number), but opinions differ on how best to ensure that it remains a small contributor.

It is clearly understood that different cars pollute at different levels, yet there is no such understanding for aircraft. In fact, the 1980s workhorse, the MD82 generates 21% more CO2 than a modern-day A319. Given the longevity of aircraft (it is not unusual for 30-year-old to still be operating commercial flights), a mix of carrot and stick is required - airlines need to be incentivised to operate the cleaner, newer technology while being subject to regulations once aircraft reach a certain age

Within Europe, it is generally recognised that including aviation in EU Emissions Trading Scheme (ETS) is considered the best solution to address aviation emissions in the medium-term (from 2011 onwards). Nevertheless, the industry is being asked to consider what else can be done. easyJet argues that, whilst the majority of action should rightly come from the industry itself, politicians should take a lead and, using the same philosophy that has reduced aircraft noise emissions, should seek to remove 678 oldest, dirtiest aircraft from Europe’s skies by banning any aircraft built before 1990 from operating after 1st January 2012 – the date that aviation is intended to become fully included in the ETS.

Introduction

Older technology aircraft are less environmentally efficient than newer aircraft; this is primarily driven from the engines (older technologies with high fuel usage emit more CO2 and NOx than newer engines for the same thrust). According figures from Airbus Industrie , a 1980s-vintage MD82 generates 21% more CO2 per seat than an A319 in an equivalent seating layout; and easyJet’s own operating data showed the A319 to be 15% more efficient per seat than the Boeing 737-300. Boeing recently claimed that the 787-9 aircraft will burn 27% less fuel per passenger than the older-generation A340-300 that it could replace in some fleets.

In addition, over time the fuel consumption of a jet engine deteriorates with use, reducing the environmental performance of the aircraft. Much of this deterioration can be recovered by doing performance restoration maintenance on the engines, but some performance is always lost. Hence, even when comparing between two aircraft of the same make and model, the older aircraft will have a worse environmental performance than the younger one (although this effect is smaller – in the order of 5% over a 25 year life).

According to data from AirCraft Analytical System (ACAS), an aviation industry market information provider, there were 3,622 western-built passenger and freight aircraft with more than 120 seats registered in Europe and the CIS in February 2007 (or the freight equivalent). Assuming the average ‘old’ aircraft generates 25% more emissions per passenger than newer replacement aircraft and that ‘old’ aircraft represent 20% (one fifth) of the fleet; replacing the old aircraft with more environmentally efficient aircraft could save 5% of European aviation emissions.

Collective action has been successful on other aviation environmental issues in the past, namely:

• Aircraft Noise (the creation of noise ‘chapters’ followed by the exclusion of the worse chapters of aircraft)
• NOx and particulates (achieved by requiring improved performance from new engines

The aircraft noise requirements had the benefit of removing old, Smokey engines from the fleet. Both of these issues had local quality benefits at airports and much of the momentum for change came from local lobbying. This shows that noticeable environmental gains can be achieved by getting rid of the worst polluters. The agreement to ban the operation of aircraft below a certain noise chapter was achieved via an agreement in the ICAO Assembly, which set an agreed time-table for phasing them out. The NOx reduction targets were agreed though the Committee on Aviation Environmental Protection (CAEP – administered by ICAO) and are set for new engine designs (the benefits of which slowly diffuse through the fleet as new aircraft are delivered). Because of this concerted action today's aircraft are typically 75 per cent quieter than jets in the 1960s

In advance of aviation entering EU ETS, what is needed is a proxy for the environmental performance of an aircraft, so that the worst offenders can be removed from the skies.

The proposal

Airlines using aircraft after they value is fully written-down may be good for the airline, but it is not for the environment (especially for 1st world airlines – the sooner they dispose of aircraft the faster the latest technology diffuses to 2nd and 3rd World airlines). The simplest solution would be to mandate that transport aircraft must be removed from the register of aircraft (currently managed at a national level throughout Europe) after they reach a certain age. European Airlines should be given a fixed time scale to start complying with this regulation, with five years being the shortest practical timescale for compliance (the manufacturers still have reasonable spare capacity in 2012 – and some of the targeted aircraft should have been scheduled to be retired before then). Announcing the requirement now would alter airline behaviour from next year (most ailrines’ plans for the winter season will be fairly firm by now), so that many of the oldest aircraft will have left the fleet long before the end of 2011.

The simplest limit is to say that, as of 1st January 2012 (i.e. the date all of aviation goes into EU ETS) no transport aircraft built before 1st January 1990 will be allowed to remain registered in the EU and the requirement would then roll forward each year. The EU could simply mandate this by issuing an appropriate directive. This also has the advantage of capturing freighter aircraft – often where older aircraft end up after being used for passenger transport. Counting backwards, there are 678 western built passenger and freighter aircraft registered in Europe and the CIS that are more than 17 years old today (i.e. built before February 1990). This represents 19% of the European fleet and, if they were all replaced today, this could represent a saving of total emissions from European aviation of 4-5%.

Not only will this noticeably improve the environmental performance of the European aviation industry (with respect to CO2 per passenger km which will lead to an absolute reduction in emissions for a given level of flying), it will also deliver noticeable environmental benefits (NOx, particulates etc) to the local areas and residents around EU airports.

Setting the limit at 20 years would too stringent, as many current generation of aircraft such as the A320 and 747-400 would be captured - around 30% of the current fleet would be affected (1068 aircraft are over 15 years old at present). Setting the limit at 25 years is probably too lenient, as this is fairly close to the point most airlines retire older aircraft at – only 9% of the current fleet would be affected (346 aircraft are over 20 years old at present).

Going forward this proposal would also accelerate the diffusion of the latest technology aircraft into the European fleet by reducing the average time aircraft remain in the fleet. The net effect of this would be to increase the rate of improvement in environmental efficiency (currently running at 1% per year).

All EU airlines would be treated the same (non-discrimination) and while the least environmentally efficient European airlines may complain that this would put them at a disadvantage to non-EU based airlines, surely it is right for Europe to get its own house in order before preaching to the rest of the world?

Why not use the noise “Chapters”?

easyJet considered maintaining the existing aircraft classification system of “Chapters” that were established for the reduction of aircraft noise, given that the noise certification of an aircraft (+engine combination) is also a reasonable proxy for aircraft emissions - the more efficiently the engines generate thrust and the aircraft generates lift, the quieter it is. Since 1 January 2006, the Chapter 4 standard has applied to all newly certificated aircraft but current ICAO agreements allow Chapter 3 compliant aircraft to fly ‘unrestricted’. However, EU Directive 2002/30/EC allows ‘marginally compliant’ aircraft (those who only just meet Chapter 3 noise requirements) to be restricted from certain airports where noise is a problem.

At its most simple, the EU could apply the restrictions available in Directive 2002/30/EC and restrict marginally compliant aircraft from all EU airports instead of simply on an as needed basis. However, the problem of using the existing definition of marginally compliant aircraft is that many aircraft type only fall foul of the definition with certain engines and MTOW. For example, the MD87 can be considered to be marginally compliant but the MD82 not. The net effect of this is that fewer than 200 aircraft (out of a fleet of 3,622) would be removed from the skies with an implied emissions saving of less than 2%.

Appendix

Details of the western-built aircraft in the European fleet that would be affected