A conveyance such as a wheelchair that includes a seat assembly and a chassis. The chassis comprises a central frame member disposed substantially along the centerline of the wheelchair. The central frame member includes portions for connecting to or supporting one or more front casters, a seat assembly, one or more drive wheel assemblies, an energy source (e.g., one or more batteries), rear anti-tip wheels, and/or at least one footplate. The central frame member is disposed substantially along the centerline of the wheelchair and structurally distributes of the weight of the seat assembly (and optionally the weight of the energy source) to the supporting drive wheels and casters. In this manner, a clean-looking, simple, and lightweight chassis structure is provided for a conveyance.