The Helicarrier is an advanced aerial vehicle with a design and function closely resembling that of a modern aircraft carrier. Specifically, the Helicarrier is designed to be capable of sustained, independently-powered flight, via four, massive engines that provide the lift needed to keep it in the air. S.H.I.E.L.D. relied on Helicarriers as highly strategic mobile bases from which they could perform a number of effective reconnaissance, stealth deployment, or direct strike operations.