He also writes for the Globe and Ma

He also writes for the Globe and Mail.
Even Bombardier admits that Skreemr is far from reality.
It might be possible, he writes, for Skreemr "maybe in the distant future ... to fly passengers across oceans at very high speed."
Let's get real: Scramjets are decades away from commercial airliners, and there are several technical challenges that engineers still need to overcome first.
Sonic boom
One big problem is heat.
Objects traveling past Mach 5 can reach upwards of 980 C (1800 F), and there is a limit to the type of materials that can withstand those kinds of temperatures.
The sonic boom is also all but guaranteed when an object breaks the sound barrier, and is a menace in urban areas, meaning that the Skreemr could only travel at supersonic speeds when passing over undeveloped areas.
Bombardier, however, says he has figured that last bit out.
The Skreemr would launch with an electric launch system, allowing it to accelerate at a high speed, before igniting liquid-oxygen and kerosene rockets to help it reach Mach 4 (at which point the scramjet engine would kick in).
Or, alternatively, the plane would launch without rockets initially and could switch to the scramjet engine only when flying over ocean.
A hybrid rocket and jet engine is being developed by Reaction Engines with joint funding by the UK and BAE Systems, which could one day lead to a new supersonic airliner.