Ezekiel 1:22

And over the head of the living creatures there was the likeness of a firmament, like the terrible crystal to look upon, stretched forth over their heads above. And under the firmament were their wings straight, the one toward the other: every one had two which covered on this side, and every one had two which covered on that side, their bodies. And when they went, I heard the noise of their wings like the noise of great waters, like the voice of the Almighty, a noise of tumult like the noise of a host: when they stood, they let down their wings. And there was a voice above the firmament that was over their heads: when they stood they let down their wings."

It would appear from this paragraph that the wings were held out straight when this incredibly strange contraption moved, and that the wings were "let down" when it stopped. Thus the noise of the wings was apparently manifested without any movement of the wings, but independently of them. The movement from one place to another was effected solely by the will of Him that sat on the Sapphire throne, who, of course, needed neither wings nor wheels to move from one place to another. The great noise would then symbolize the great importance and significance of God's attention and presence being devoted to any particular place or occasion.