During a remarkable congressional hearing, former American intelligence official David Grusch revealed that the US government conducted a "multi-decade" programme aimed at collecting and reverse-engineering crashed unidentified flying objects (UFOs).
Grusch, who was in charge of investigating unexplained anomalous phenomena within a US Department of Defence agency until 2023, spoke before the House oversight committee in Washington, shedding light on the issue of alien life and technology, as reported by the Guardian.
If I remember it correctly from the point of view of the ship it looks like the propulsion becomes less effective, tough I confess my recolection of what I learned about the General Theory Of Relativity in my Physics degree almost 3 decades ago (which I never completed, by the way, so I’m an EE not a Physicist) breaks at around this point so I might be completelly off on this.