Here we go again with another super-cool design for an airliner that flies faster than the speed of sound.
The latest new concept design is called Skreemr, which -- if developed -- supposedly would carry 75 passengers from London to New York in 30 minutes.
Come ON already. Seems like every time we turn our heads, we're hearing about another proposed supersonic passenger plane.
By now, it's getting hard to separate engineers' dreams from what's likely in a real-world economy. In July, Airbus was granted a patent for a supersonic airliner that would fly from New York to London in 90 minutes.
Airbus tried to tamp down all the excitement by saying that this was just one of hundreds of concept patents filed every year.
Last year, Lockheed Martin announced it was working with NASA on a supersonic airliner that would fly from New York to LA in 2.5 hours.
Now, there's the Skreemr -- which looks downright sexy, especially to an aviation enthusiast or engineer.
But if you're among last year's 3.3 billion airline passengers, this is kind of meaningless, at least for now.
How would it work?
Here's how it might work: Skreemr's concept designer Charles Bombardier and artist Ray Mattison propose that this plane would be powered by a scramjet engine.
Unlike conventional jet engines, scramjet engines have virtually no moving parts.
And unlike rockets, scramjet engines would burn oxygen from the atmosphere instead of having to carry heavy tanks full of oxygen.
The Pentagon launched a small, unmanned scramjet aircraft in 2013, which hit Mach 5 -- five times the speed of sound.
Nonetheless, that's a long way from being an airliner.
The man with the plan
Bombardier is an inventor known for his visionary transportation concepts.
Yes he's related to the Canadian aircraft manufacturer.
He has posted more than a few unique ideas on his website including a "futuristic, electric driverless hearse," a sail boat drone and a military submersible aircraft called a Subplane.
"These concepts are far from perfect, but they're meant to get people thinking," Bombardier's website says.
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.
