an air conveyor is provided comprising a plenum chamber including a deck plate , a plurality of first apertures in the deck plate for directing air from the plenum chamber to convey articles , and a plurality of protuberances extending from the deck plate for receiving bottoms of the articles . the protuberances preferably protrude from the deck plate far enough to support the articles above accumulated slide resistance increasing material . the air conveyor deck plate preferably also includes a plurality of second apertures for directing air from the plenum chamber to aid in lifting the articles .