Xanthium (Movie)

The Xantium is an Autobot ship, It brought the second wave of Autobots to Earth, After that N.E.S.T took control of it and rigged it up to a decommissioned shuttle.

Dark of the Moon film
Upon Discovering the existence of the of the long lost Autobot ship, The Ark, Optimus and Ratchet fly to the Moon in it to recover Sentinel Prime and the Space bridge pillars.