Japanese aim high with Concorde-san

The Japanese government is developing a supersonic passenger aircraft, three times the size of Concorde, which could fly between Tokyo and London in little more than five hours.

Concorde-san, as the new project is likely to become known, is intended to carry 300 passengers, about the same size as the current generation of sub-sonic jumbo jets. It will fly at a speed of Mach 2.4 compared to Mach 0.85 for a Boeing 747-400, drastically reducing the current flight time of 11 to 13 hours between Japan and western Europe.

Financially viable supersonic travel is one of the holy grails of the aerospace industry. But the high cost of the technology, has so far rendered projects like Concorde unprofitable. The Japanese aircraft is being developed by the Ministry of Trade and International Industry in collaboration with a consortium of private companies including Mitsubishi Heavy Industries.

Last year, the ministry spent 3.75bn yen (pounds 20m) on the research and development of a Mach 5 supersonic engine known as HYPR, and it is hoping to spend 800m in 1998 on developing materials for building a supersonic aircraft body. The aluminium alloy currently used in passenger jets cannot withstand the 200 degrees centigrade temperatures generated through wind resistance during supersonic flight, and Mitsubishi hopes to come up with a carbon fibre compound alloy capable of performing the task.

Japan's aerospace industry has had little impact on the international market, largely because the country's post-war "peace constitution" forbids it from exporting any military equipment or technology. A number of civilian aircraft have been developed but they have all been commercial failures, and the latest effort, a small passenger jet called the YSX, is a "paper plane" and has not been manufactured in large numbers.

"They've proved that they can build aircraft, but the problem is selling and supplying them in competition with far more experienced companies like Boeing and Airbus," said Paul Lewis, Asia editor of Flight International. "Their imagination has been caught by the dream of producing something futuristic for the 21st century, but if they've continually failed to build a small 100-seat jet, it's unlikely that they'll ever do it on their own."