(1) one member of an affiliated group is the owner or lessee of an aircraft, and
(2) such aircraft is not available for hire by persons who are not members of such group,
For purposes of subsection (a), the determination of whether an aircraft is available for hire by persons who are not members of an affiliated group shall be made on a flight-by-flight basis.
For purposes of subsection (a), the term “affiliated group” has the meaning assigned to such term by , except that all corporations shall be treated as includible corporations (without any exclusion under ).