Montreal - New supersonic passenger planes designed by Boeing and other manufacturers offer the chance to connect continents faster than ever. However, these future aircraft at supersonic and hypersonic speeds could also affect the environment at a much higher rate compared to today's air transport vehicles.

Three startup companies - Aerion, Boom, and Spike - have unveiled plans to develop supersonic aircraft that can fly at more than twice the speed of sound (about 1,234 km/h). Boeing recently introduced the concept of a hypersonic aircraft for military or commercial customers designed to travel at more than 5,700 km/h.

Faster than a bullet, says Kevin Bowcutt, a Boeing engineer who leads hypersonic aircraft studies at Boeing. A traditional trans-Atlantic or trans-Pacific flight takes 6, 12, 14 hours depending on your departure location. With a hypersonic plane, it will take only two or three hours, shortening the trip to the point where one can go to Europe or Asia and return in one day.

On the other hand,

These supersonic aircraft will burn five to seven times more fuel than the standard aircraft that are flying today,
says Anastasia Kharina, an aerospace engineer at the International Council on Clean Transportation (ICCT).

Kharina also says that hypersonic aircraft would be even more polluting than slower supersonics because speed kills fuel efficiency.

No wonder, the high fuel consumption was one of the reasons for the retirement of the Concorde in 2003. For now, the Boeing hypersonic jet is just a conceptual plan that could take 20 years or more to get into service, while supersonic aircraft can emerge by the end of the next decade.

These new high-speed planes, however, are moving against environmental issues. Many companies and governments are planning to eliminate carbon emissions by the mid of 21st century, around the same time that Boeing's hypersonic aircraft can hit the market.