(a) As used in this subchapter, unless the context otherwise requires, "common carrier" means any person, firm, or corporation which undertakes, either directly or indirectly, to transport members of the general public as passengers for compensation whether over regular or irregular routes.
(b) For the purposes of this subchapter and subject to the terms and conditions of coverage, the term "uninsured motor vehicle" shall be deemed to include an insured motor vehicle where the liability insurer thereof is unable to make payment with respect to the legal liability of its insured within the limits specified therein because of insolvency.