Although the UNSC had issued standing orders to recover all Covenant or alien technology available from the battlefield, and had spent considerable effort negotiating with the Sangheili for access (and bribing Kig-yar pirates), even after the War of Vengeance there were significant and severe gaps in UNSC understanding of Covenant and Forerunner technologies. Most of the advances that have made the UNSC Navy the most powerful space force since the collapse of the Covenant were already well under way during the Great War, and are mostly human derived, spurred by necessity and human ingenuity. A very small number of technologies have been entirely derived from Covenant systems - the Shaw-Fujikawa Translight Engine 2553 upgrade uses Covenant calculations for slipspace navigation, shield techn