When it comes to space, there is a problem with our human desire to see and experience everything. A significant problem. The problem, after all, is space. It’s too big. Even at the highest speed allowed by the Universe, it would take us years to reach our nearest neighboring star.

Yet another human motivation is to overcome challenges. And that’s just what NASA engineer David Burns has been doing in his own time. He has developed a concept for an engine that he claims could accelerate to 99 percent of the speed of light, all without the need for fuel.
He uploaded it to NASA’s technical reporting server under the title “Helical Engine” and, on paper, it works by taking advantage of the way mass changes at relativistic speeds, those close to the speed of light in a vacuum.

It is understandable that this document has generated similar enthusiasm to the early days of EM Drive. And certainly, there have been headlines claiming that the engine can “break the laws of physics.”

However, while this thought is intriguing, it’s unlikely to break the laws of physics any time soon.

Burns presents a box with a weight inside, strung on a line, and with a spring at each end that bounces the weight back and forth as a thought experiment to illustrate his idea. In a vacuum, such as space, this has the illusion of the entire box twisting, while the weight appears to remain motionless, like a stabilized gif around the weight.

The box would stay in the same position in general, but if the mass of the weight were to increase in only one direction, it would cause a stronger push in that direction, and thus a push.

This should not be entirely conceivable according to the concept of conservation of momentum, which states that the momentum of a system remains constant in the absence of external influences.

But! There is a loophole in special relativity. Special relativity states that things gain mass as they approach the speed of light. Therefore, if the weight is replaced by ions and the box is replaced by a loop, the ions can potentially move faster at one end of the loop and slower at the other.

However, Burns’ drive is not a closed loop. It is helical, similar to a stretched spring, hence the name “helical motor”.

“The engine accelerates the ions confined in a loop to moderate relativistic speeds, and then varies their speed to make slight changes to their mass. The engine then moves the ions back and forth along the direction of travel to produce thrust,” he wrote in his abstract. .
“The engine has no moving parts other than ions traveling in a vacuum line, trapped within electric and magnetic fields.”

Sounds pretty smart, doesn’t it? And it is, theoretically. However, it is not without considerable practical difficulties.

The helical chamber, according to New Scientist, would have to be quite large. To be exact, it measures around 200 meters (656 feet) long and 12 meters (40 feet) in diameter.

However, what happens in the vacuum of space? It could possibly work. “The engine itself could reach 99 percent of the speed of light given enough time and power,” Burns told New Scientist.
So the bottom line is that Burns’ idea is intriguing and very clever, but it has to work in real life and for that, we’ll have to wait as a lot of experiments are required before we get to the final blueprints for the spaceship.