Abstract: A rotor assembly is provided, along with gas turbine engines for its use. The rotor assembly may include a spool defining a plurality of apertures arranged in a first row and spaced circumferentially around the spool, wherein each aperture of the plurality of apertures extends through the spool from a radially inward-facing surface to a radially outward-facing surface; and a blade assembly comprising at least two blades connected to each other via a platform, wherein each blade extends through a respective aperture.