A lordotic guard and method for guiding a bone removal device to form an implantation space in the human spine and, if desired, for inserting a spinal implant into the implantation space. The aircraft includes an airframe, a pair of fins attached to a rear portion of the airframe, a pair of dihedral braces attached to a bottom portion of the airframe, a first thrust-vectoring module and a second TV module, and an electronics module. Thereafter, communications that are received by the adaptive service bus are processed in accordance with \u201crules\u201d established by the configurations. The text is delivered to users of which the retrieval condition satisfies the similarity.