An airfoil includes an airfoil wall that defines a leading end, a trailing end, and first and second sides joining the leading end and the trailing end. First and second ribs each connect the first and second sides of the airfoil wall. Each of the first and second ribs define a tube portion that circumscribes a rib passage and includes cooling apertures, and first and second connector arms that solely join the tube portion to, respectively, the first and second sides of the airfoil wall. The airfoil wall and the first and second ribs bound a cooling channel there between. The cooling apertures of the first and second ribs open at the cooling channel such that there is a cooling circuit in which the rib passages of the first and second ribs are fluidly connected through the cooling apertures and the cooling channel.