Greener flying? Expect some turbulence

After safety scandals and security rows, the airline industry is trying to clean up its image with cleaner, greener engines. But it's going to be a bumpy ride, says Nick Harding

In the next two weeks, the annual Christmas exodus begins and millions of people around the globe will take to the skies and head off like migrating birds for festive breaks. Cue the usual horror stories of weather delays and Spanish/French industrial action.

This year, for travellers heading to the US, there is a new strand to this annual narrative: the unwelcome pat-down. Thanks to the installation at many American airports of new body-scanning technology by the Transportation Security Administration (TSA), there is rising outrage at the intrusive nature of security measures flyers are being subjected to. The scanners can see through clothing and map anatomically precise images of people who pass through them. And for those passengers who exercise their rights to opt out of these new checks, the alternative is equally embarrassing: the "enhanced" pat-down includes contact with breasts and genitalia.

Videos posted online depicting flyers' interactions with TSA agents, including pat-downs of children, have led to several anti-flying websites and a popular movement calling for a flying boycott. All the while, debate is raging at just how effective these new measures are. Some argue they will cause an increase in road deaths as travellers choose to drive, and earlier this month, an Israeli security expert told Canadian legislators that the machines are "expensive and useless", which is why the Israelis, known as among the best at airport security, do not use them.

Add to this debate the jitters sent through the aviation industry last month when an Airbus 380 jet engine exploded on a Qantas flight from Singapore to Sydney, and it would appear there has never been a worse time to fly. Business has certainly been adversely affected by the image of the shredded engine of flight QF32, which suffered a catastrophic explosion on 4 November. A subsequent investigation found that the British-manufactured Rolls-Royce T900 engine was destroyed following an oil fire caused by a faulty turbine component. Qantas grounded all six of its super-jumbos while tests were conducted and although it maintains there is "no risk to flight safety", many of its A380 T900 engines will now have to be overhauled or replaced. It has begun legal action against Rolls-Royce.

Set against this tumultuous backdrop, it is easy to lose sight of the fact that the aviation industry is actually standing on the cusp of a new age of technological advancement that should make jet travel greener and more efficient.

A new generation of more efficient, quieter aircraft jet engines carrying names such as the TXWB, the PurePower PW1000G and the T1000 are due for commercial introduction over the next two years. These new multimillion-pound developments will, according to their makers, Rolls-Royce and Pratt & Whitney, get a new age of more environmentally friendly air travel off the ground.

Next year, Derby-based Rolls-Royce is set to begin commercial operation of its T1000 engine, which will power Boeing's groundbreaking Dreamliner 787 aircraft; it will be the first aircraft to be built from composite materials. Two years after that, Rolls-Royce is scheduled to launch the TXWB, powering the new Airbus 350. The company has spent years of man hours and billions of pounds developing these engines. While Rolls-Royce concentrates on powering wide-body transcontinental aircraft, its rival Pratt & Whitney hopes to secure the narrow-body market with the PW1000G, which is scheduled to enter commercial service in 2013. Its geared turbo fan technology allows different components in the engine to run at varying, more efficient speeds, which, the manufacturer claims, will improve fuel consumption by up to 20 per cent, cut carbon emissions by more than 3,000 metric tons per aircraft per year, and also slash aircraft noise by up to 75 per cent. It is being hailed as a "game-changer".

All three new engines have been developed in an attempt to address the seismic shifts the aviation industry has seen in the past decade in terms of environmental legislation and increasing fuel costs.

But creating a new commercial jet engine comes at a cost. It is a mammoth undertaking reflected in the price tag of the current market leaders, which sell for between $10m and $20m and, depending on the age and type of an aircraft, are often worth more than the aircraft they are fitted to. Even in the case of new aircraft such as the A380, which carries 525 passengers and costs around $300m, the four $20m engines needed to power it still account for a large percentage of the overall cost.

It took Rolls-Royce four years to develop a prototype TXWB just to the stage where it could be run through a flight profile on a static test bed. This initial run, made earlier this year, was the first stage of at least three years of testing and tweaking which the engine must complete before it is ready to carry passengers. Likewise, the T1000 was first tested on the ground in 2006, took to the air for the first time in 2007 and is not scheduled for commercial use until 2011.

The testing regime for any new design of jet engine is exhaustive. They are encased inside giant freezers and frozen to minus 40C to assess their cold-start ability, water is poured into them at a rate of 30,000 gallons an hour to ensure they operate in rainstorms, and each component is carefully assessed for damage using an array of technology including X-rays and electron microscopes.

One of the most crucial tests for a prototype engine assesses its ability to cope if a fan blade detaches itself from the main fan. In such a malfunction the engine needs to be able to shut down effectively and contain the blade inside the engine casing. The titanium-bladed fans are encased in a Kevlar-wrapped aluminium housing and spin so fast that the effect of the impact of a blade coming loose is equivalent to the impact of a one-ton car being dropped from a 200ft cliff. A loose blade could rip through a wing or fuselage. Fan blade tests use explosives to blow blades from the fan at maximum take-off speed. The test destroys the engine.

The underpinning theory of jet propulsion is the same in the new generation of engines as it was in the first jet engine developed by Frank Whittle in 1937. Cold air is sucked into a core, where it is condensed and forced into a combustion chamber and then ignited with fuel to create a gas jet fired through a turbine. Today's computer-controlled engines, however, bear little resemblance to their historic predecessors. In modern engines the turbine blades spin so fast, each one has the equivalent horsepower of a Formula 1 racing car. They have to operate in temperatures that reach 1,700 degrees, so the materials used to build them need to remain incredibly strong under immense stress. Rolls-Royce, in collaboration with several universities and research centres, formulates its own alloy compositions to handle the extreme conditions. Normal metals are composed of millions of interlocking crystals and the joins between those crystals are potential weaknesses. Rolls-Royce "grows" engine parts at its hi-tech forge from single crystals.

The cost-intensive development programmes involved in bringing a new jet engine to market explain the price tag of the finished product. For many airlines, it is simply too expensive to buy and maintain engines so, increasingly, they are leased to airlines by banks such as RBS, which has an aviation division, aviation finance companies, and manufacturers which offer lifetime-maintenance programmes. Rolls-Royce monitors the engines it leases in real time using internal sensors to relay data via satellite to an operations centre, where a team of technicians monitors the performance of each engine and analyses the data for any problems.

Bob James is a jet engine expert and managing director of leasing firm AerFin. He explains: "The new engines coming to the market are highly technologically advanced products. To bring an engine from start up to service can take eight to 10 years. Given the capital-intensive nature of the industry, it is much more beneficial for airlines to not own assets."

The complex finances of airlines and the long shelf-life of aircraft and engines mean that not everyone is eager to embrace revolutionary developments which will effectively date fleets of older aircraft. In the case of Pratt & Whitney's PurePower PW1000G engine, some industry experts say it will be so advanced it will devalue existing equipment.

"It is a major technological step forward and one we should be embracing," James says. "However, the problem is that it will be competing with other products that still have a long way to go in their operative lifespans and if airlines accept it, which in principle they should, it would mean an adverse impact on the residual value of fleets. We'd all like to see it but the knock-on effect is the potential for a major reduction in the values of older aircraft. Because aviation products like engines and aircraft have such a long development and are designed to last up to 30 years, if you change the dynamics mid-life, you have major issues with funding. It is a multitrillion-dollar industry and there are a lot of powerful people that don't want to see aircraft developed."

It appears that as far as jet travel is concerned, the flight to a more efficient future looks set to be bumpy.