propulsion

On arrival, the service module, which has the spacecraft's primary propulsion system, separates from the crew module.

Alia is one of the most advanced projects, among dozens of firms exploring electric propulsion in aviation.

The UK's propulsion test was the result of a three-way collaboration between the UK government, industry and the US government.

"Also, when we bring in more software defined, 'smarter' vehicles, the ability to manage fleets remotely will help bring down costs as well. So the revolution will be about propulsion and software."

The country becomes just the second after the UK to receive Washington's elite nuclear propulsion technology.