30 April 2006
Twenty years ago, engine makers focused most of their energy on speed. Today, technology is driven by the need to cut costs and increase profits. The environment figures in these costs. So aircraft engine design has tended to focus on the environment, along with making engines lighter, more durable and more efficient.
The major engine manufacturers like General Electric, Pratt & Whitney, Rolls-Royce and Snecma are all pursuing improvements and new technologies of the future. The CFM venture is working very hard to make things happen.The environmental issues being addressed in the development of these new technologies are noise, local air quality and climate change.
The sizeable reductions in noise and emissions envisaged by the regulatory regime will require fundamental changes in the design of aircraft and their powerplants. While technology addressed to climate change may be a long-term objective, the shorter term objectives include a l0Db reduction in current noise levels by 2010 and a 70 per cent reduction in NOx emissions, relative to the current ICAO CAEP standards.
A range of engines of varying sizes are being developed with advanced ideas such as different engine cycles and materials like ceramic matrix composites. Other developments being pursued are advanced staged combustors with more complex control systems for second-generation supersonic transports, because combustor configuration has a profound influence on emissions.
A rock band (110 decibels) may be louder than a commercial jet flying at 1,000 ft (100 decibels). But the difference is that people accept and enjoy the noise level of the band but are becoming more intolerant about the noise levels of aircraft in their neighbourhoods.That's part of the contradiction, because the aviation industry claims that people are flying more frequently and further. And that is a fact borne out by the statistics. But people also want a better living environment. So, although aircraft have become progressively quieter over the years as a result of restrictive legislation and technological advances, there has been no let up in the number of complaints about noisy aircraft and airports.
Whilst tremendous progress has been made in reducing emissions from aero engines, manufacturers continue to seek further improvement. Soot, smoke, hydrocarbon sand carbon monoxide have all but disappeared, and emissions of nitrogen oxides have been reduced by advanced combustion technology. Carbon dioxide emissions are proportional to the amount of fuel burnt. Fuel burnt per seat has halved since the 1 960s due to improved engine technology and lighter aircraft designs. In addition, higher passenger load factors means that less capacity is wasted. On average fewer than 30% of seats available are now left empty, compared to around 50% thirty years ago.
Some airports have tried to establish some parameters.
Twenty years ago, engine makers focused most of their energy on speed. Today, technology is driven by the need to cut costs and increase profits. The environment figures in these costs. So aircraft engine design has tended to focus on the environment, along with making engines lighter, more durable and more efficient.
The major engine manufacturers like General Electric, Pratt & Whitney, Rolls-Royce and Snecma are all pursuing improvements and new technologies of the future. The CFM venture is working very hard to make things happen.The environmental issues being addressed in the development of these new technologies are noise, local air quality and climate change.
The sizeable reductions in noise and emissions envisaged by the regulatory regime will require fundamental changes in the design of aircraft and their powerplants. While technology addressed to climate change may be a long-term objective, the shorter term objectives include a l0Db reduction in current noise levels by 2010 and a 70 per cent reduction in NOx emissions, relative to the current ICAO CAEP standards.
A range of engines of varying sizes are being developed with advanced ideas such as different engine cycles and materials like ceramic matrix composites. Other developments being pursued are advanced staged combustors with more complex control systems for second-generation supersonic transports, because combustor configuration has a profound influence on emissions.
A rock band (110 decibels) may be louder than a commercial jet flying at 1,000 ft (100 decibels). But the difference is that people accept and enjoy the noise level of the band but are becoming more intolerant about the noise levels of aircraft in their neighbourhoods.That's part of the contradiction, because the aviation industry claims that people are flying more frequently and further. And that is a fact borne out by the statistics. But people also want a better living environment. So, although aircraft have become progressively quieter over the years as a result of restrictive legislation and technological advances, there has been no let up in the number of complaints about noisy aircraft and airports.
Whilst tremendous progress has been made in reducing emissions from aero engines, manufacturers continue to seek further improvement. Soot, smoke, hydrocarbon sand carbon monoxide have all but disappeared, and emissions of nitrogen oxides have been reduced by advanced combustion technology. Carbon dioxide emissions are proportional to the amount of fuel burnt. Fuel burnt per seat has halved since the 1 960s due to improved engine technology and lighter aircraft designs. In addition, higher passenger load factors means that less capacity is wasted. On average fewer than 30% of seats available are now left empty, compared to around 50% thirty years ago.
Some airports have tried to establish some parameters.
© Bahrain Tribune 2006
