A pulse detonation combustor (PDC) assembly includes an upstream chamber forming an inlet plenum, a downstream chamber including a downstream portion of at least one PDC tube, and an integrated PDC head coupled to the upstream chamber and the downstream chamber. The integrated PDC head is configured to facilitate fuel injection and ignition within the PDC tube. The PDC tube includes an inner seal surface and an outer seal surface configured to mate with the inner seal surface, wherein the inner seal surface includes an elevated section thereon that engages with the outer seal surface such that the PDC tube is free to partially pivot about a longitudinal axis thereof.