A mechanically attached thermal protection system (MATPS) includes an insulating tile having a top surface, a bottom surface, and a plurality of access holes that extend through the insulating tile from the top surface to the bottom surface. A plurality of brackets include a first end attached to the insulating tile and a second end including a mounting hole therethrough, the second end being positioned proximate the bottom surface of the insulating tile. A plurality of fasteners are positioned proximate the bottom surface of the insulating tile and at least partially positioned within one of the access holes so as to be accessible from the top surface of the insulating tile through one of the plurality of access holes. A MATPS including a plurality of air channels within the insulating tile and a method for sealing these air channels to those within an adjacent structure is also described herein.