[@Nallore] I was doing some research on the FTL capabilities of the Halo and Star Wars.

A typical UNSC Charon-Class Light Frigate in the 2530s was capable of 2-3 Lightyears per 24 Hours. That means a galactic transit would take 110-165 years in that ship.

Covenant ships are capable of a recorded 912 Lightyears per 24 Hours. That ship would be capable of a galactic transit in only 131 days.

UNSC Infinity-Class are now on par with the Covenant's.

A SW Class 1 drive is capable of making a full galactic transit (from one end to the other) within only a few days or hours.

Sounds to me like the UNSC's alliance with the Republic should include replacing the UNSC engines.