Helical engine

{{Short description|Proposed spacecraft that violates the laws of physics}}

The Helical engine is a proposed spacecraft propulsion drive that, like other reactionless drives, would violate the laws of physics.{{Cite web|last=Siegel|first=Ethan|title=For The Last Time, No, A NASA Engineer Has Not Broken Physics With An Impossible Engine|url=https://www.forbes.com/sites/startswithabang/2019/10/17/for-the-last-time-no-a-nasa-engineer-has-not-broken-physics-with-an-impossible-engine/|access-date=2020-12-05|website=Forbes|language=en}}{{Cite web|last=Cartwright|first=Jon|title=NASA engineer's 'helical engine' may violate the laws of physics|url=https://www.newscientist.com/article/2218685-nasa-engineers-helical-engine-may-violate-the-laws-of-physics/|access-date=2020-12-05|website=New Scientist|language=en-US}}{{Cite web|last=Koberlein|first=Brian|date=2019-10-16|title=NASA Engineer Has A Great Idea for a High-Speed Spacedrive. Too Bad it Violates the Laws of Physics|url=https://www.universetoday.com/143741/nasa-engineer-has-a-great-idea-for-a-high-speed-spacedrive-too-bad-it-violates-the-laws-of-physics/|access-date=2020-12-05|website=Universe Today|language=en-US}}

The concept was proposed by David M. Burns, formerly a NASA engineer at the Marshall Space Flight Center in Alabama, in a non-peer-reviewed report published on a NASA server in 2019 describing it as "A new concept for in-space propulsion is proposed in which propellant is not ejected from the engine, but instead is captured to create a nearly infinite specific impulse".{{Cite web|title=NASA Technical Reports Server (NTRS)|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20190029294.pdf|access-date=2020-12-05|website=ntrs.nasa.gov|date=19 August 2019 }}

The Helical engine accelerates ions that are confined in a locked loop. Once they are accelerated, the system changes the velocity of the ions in order to change their momentum. Afterward, Burns hypothesized that the engine, by moving the ions along its axis, could produce thrust. The proposed engine is mainly intended to be used to maintain the orbit of satellite stations during long periods of time without the need of refueling.{{Citation|last=Burns|first=David M.|title=Helical Engine|date=2019-08-16|url=https://arc.aiaa.org/doi/10.2514/6.2019-4395|work=AIAA Propulsion and Energy 2019 Forum|series=AIAA Propulsion and Energy Forum|publisher=American Institute of Aeronautics and Astronautics|doi=10.2514/6.2019-4395|isbn=978-1-62410-590-6 |s2cid=242520152 |access-date=2021-03-01|url-access=subscription}}{{Cite web|last=Leman|first=Jennifer|date=2019-10-11|title=A NASA Engineer Wants to Use a Particle Accelerator to Power Rockets|url=https://www.popularmechanics.com/science/energy/a29443247/particle-accelerator-power-rockets/|access-date=2021-03-02|website=Popular Mechanics|language=en-US}}