In response to the imminent threat of the private armed organization calling itself Celestial Being, the Human Reform League launched a top-secret crash program, with the intent of unlocking the secrets of Celestial Being's GN particle-drive system.
After several months, the HRL scientists managed to construct a functional, yet highly unstable GN drive. The drive's estimated power output was approximately twice that of Celestial Being's Gundam mobile suits, but due to it's unstable nature, its operational time was restricted to three minute intervals, otherwise the unstable GN Theta drive risked catastrophic (and spectacular) failure.
As the independent development of a GN drive was not part of the original Aeolia Shenburg Plan, a Celestial Being subsidiary, Sundial Group, was tasked with halting the HRL's GN development program.
Things went badly wrong, however. The GN Tieren was vaporized along with the rest of the island research facility during Gundam Dusk's final suicidal assault on the compound.
This may have use a lot of terms you'd be unfamiliar with if you aren't a fan of Gundam 00. If you want to understand these terms, I'll leave you to do research on your own. This is a design for my Gundam 00 side-story, Gundam Dawn.
Gundam (c) Bandai