[Brilliant]

“Firstly it requires a plentiful supply of electricity to convert argon into plasma and expel it with such terrific violence.”

This is actually the biggest problem with it. They will need to vastly improve the efficiency of nuclear power generators to make it work. But that may not be impossible.

[FatherofFive]

They will need to vastly improve the efficiency of nuclear power generators to make it work. But that may not be impossible.

Di-lithium crystals.

[Vaquero]

Russia to develop nuclear space engine

[dangerdoc]

power chips plc

[Talisker]

This is actually the biggest problem with it. They will need to vastly improve the efficiency of nuclear power generators to make it work. But that may not be impossible.

It's just a scaling problem - if they just use a regular fission reactor connected to a reverse-engineered ET anti-gravity generator, they can make the reactor big enough to support both the required platform size and the plasma engine thrust requirements.

Slap on some black anti-radar panels, and they're in business.