Flight stimulator

Aero-engine makers must cut emissions and reduce noise to remain competitive, says Rolls-Royce’s technology director Mike Howse who is leading the drive for new technologies to achieve sustainable development in the aerospace industry.

Dr Mike Howse thinks deeply before he answers my questions, conscious that talk can be ‘inefficient’, as he puts it. As director of engineering and technology at Rolls-Royce he has a lot he could say about the many programmes for which he is responsible.

The development of new gas turbine technologies includes crucial areas of work such as reducing noise and emissions in aircraft engines. Then there is the use of more electric technologies to reduce complexity in aerospace and marine applications, developing advanced materials, investigating the possibility of intelligent engines for unmanned combat aerial vehicles and turning the fuel cell from an experiment into a viable source of power on land, and maybe in the air as well.

As he ponders all this Howse raises his hands gently to his face. They look like a craftsman’s hands, large, worked and capable – just the sort of hands you might imagine somebody in the engine-making business would have. But this is exactly the sort of imprecise and speculative point that he would not forgive me for wasting time on.

The point is that when it comes to the development of gas turbines there are only a very few people in the world with a CV that could compare to that of Howse. He has played a leading role in the development of some of the most successful engines the world has ever seen. While, of course, he does not assemble the things himself he is a part of them. They are very much in his blood.

What, then, powers Howse’s personal engine?

Creating products for customers, he said. This might sound like a bit of cheap corporate-relations speak, but Howse has some pretty interesting and demanding customers, and keeping them happy places him at the cutting edge of technology development.

The truth is that he is a typical engineer who likes to make things work. ‘Two things motivate me most: the second thing is that that results in very technically interesting and motivating work. It gives me lots of really nice, difficult, juicy problems,’ said Howse.

‘Any engineer who is really interested in engineering has to connect himself to the customer. It’s about creating better things and things that can give value to the customer. So we want our engines to last longer, fly further. We want our ships to be more efficient, be easier to maintain and give good service. This is when the most interesting, thought-provoking and challenging problems arise.’

One such customer is the US Department of Defence, the largest single source of work for Rolls-Royce. The most significant recent contract in technology terms is the lift fan system being developed for the Joint Strike Fighter. Howse is bullish about Rolls-Royce’s technical contribution to the project. The company shipped the first blisk, or bladed disk, for the demonstrator aircraft earlier this month.

The lift fan for the short take-off and vertical landing (STOVL) variant of the JSF has to operate in extreme aerodynamic conditions by the standards of other turbine engines. It therefore has to be strong but also light. To cut the weight the fan is a blisk design, where hollow blades are friction-welded to the disk to create a single component.

‘I don’t believe anybody else could design a fan to operate in these circumstances,’ said Howse. ‘I don’t believe anybody else has friction-welded this type of blade or designed a clutch (to connect the fan to the engine) that can cope with the engine’s 29,000hp.’

The competition between Boeing and Lockheed Martin for the JSF contract hung solely on the success of the lift fan design, said Howse. ‘There was no compromise of the lift fan on the aerodynamics of the aircraft. So the success of the Lockheed bid was purely predicated on whether the STOVL [ie. lift fan] did or did not work.’

On the civil side of the aerospace business Howse was responsible for reorganising Rolls’s technology development work into three categories, known as the Vision 5, 10 and 20 programmes. These describe the technologies the company aims to acquire or develop for future generations of engines up to 20 years hence.

Howse is very careful not to reveal what, if any, are his favourite areas of research. But the civil aerospace industry has a huge challenge on its hands to improve the environmental impact of its engines. Under Howse, Rolls-Royce has set itself the target of cutting its engines’ emissions by half before 2010.

‘We are responding to the judgment that we have to deal with the environmental challenge,’ said Howse. ‘There’s no doubt in my mind that if we don’t do everything possible to deal with NOX around airports, reduce carbon monoxide as much as possible, then it could result in a restraint on the growth of the aerospace industry.’

He believes the environment will remain a competitive issue for aero-engine makers well into the future. But achieving sustainable development in aerospace will require a raft of new technologies, some of which will take years to bring into service.

‘We need electrical technologies because they are more efficient and cost effective. We need more advanced aircraft, we need different systems to reduce engine noise. We need improved combustion technologies to reduce emissions. That is the route to sustainable development.’

A key milestone on this path is the Affordable Near Term Low Emissions engine (ANTLE), an EU project led by Rolls-Royce and supported by the DTI. The project is designed to demonstrate a range of new technologies that will be commercially available by 2008.

One method of improving the cost and efficiency of an aero-engine is to employ more electric systems to increase functionality and reduce mechanical complexity. This has been done successfully in the marine sector, and now Rolls-Royce is relying more and more on the expertise of electrical engineers to bring the technology into aerospace propulsion. Howse is at the vanguard of the new approach.

‘The ultimate, which we are going to run in the ANTLE engine in 18 months’ time, has active magnetic bearings, which gets rid of the traditional balls with oil. You have a series of magnets around the shaft which are controlled to hold the shaft off the rotor, so there is no contact. The chief advantage of this system will be to improve the reliability and management of the engine.

‘The best way of getting intelligence about the engine is to have an electric current coming out of it.’

Howse believes that, as in the marine sector, aircraft engines can be configured as power cells for the whole aircraft, delivering power as electricity to run and operate other onboard systems. ‘Boeing will be doing that on the 7E7, and clearly it’s already happening on UAVs and some military aircraft.

‘So if our engines are to become more electrical we must recruit and use electrical engineers in greater areas of our activity. We will start to use electrical systems to optimise the engine in a different way than we do today. In the future this will be the direction in which the technology is developed.’

So is the logical result of all this work a totally electric aircraft that runs on a central power source such as a fuel cell?

Rolls-Royce is developing fuel cell technology for distributed power generation, but Howse believes totally electric aircraft cannot be ruled out for the future. ‘Fuel cells for aircraft are realistic to think about, because we need to. Fuel cells have been around for about 100 years. Translating that technology from an experiment into a useful application is the real challenge. Energy and power generation applications will be the first areas – aerospace is a long way off.’ Howse’s love of the possibilities of his work are manifest. ‘To be able to do this job as an engineer in the UK at Rolls-Royce is fantastic.’

He believes that people of his standing in the profession have a responsibility to promote engineering. But Howse claims the government needs to do more to ensure the supply of well-qualified and enthusiastic graduates to keep up the momentum that he and others in the UK industry have generated so far. As Howse himself proves, an industry is only as good as its best people.

For the record

Dr Mike Howse gained two degrees, special physics and general science, at Reading University in 1964. He later completed a PhD in engineering science.

He joined Rolls-Royce in 1968 and began by researching materials and aero-elasticity. In 1984, as chief engineer on the RB211 team, he was responsible for introducing the RB211-524G into service on the Boeing 747-400 and the RB211-524H on the Boeing 767. During this period he led the concept design work on the three-shaft Trent engine.

In 1989 he was appointed head of advanced engineering, responsible for the research and demonstrator programmes for both civil and military engines, becoming director of engineering for the military engine group in 1991.

In 1995 he became director of engineering (airlines), and later director of engineering (civil aerospace), overseeing the introduction of the Trent and other variants into service.

He was awarded an OBE in the millennium honours for his services to aerospace and in 2001 was appointed to the Rolls-Royce board as director (engineering and technology).

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