A.   Contracts and Leases Subordinate:
      1.   All contracts and leases between the lessees and the City shall be subordinate to the provisions of any existing or future agreement between the City and the United States, relative to the operation or maintenance of the airport, the execution of which has been or may be required as a condition precedent to the expenditure of Federal funds for the development of the airport properties.
      2.   All contracts and leases between any lessee and the City shall be subordinate to the right of the City during time of war or national emergency to lease the landing area or any part thereof to the United States government for military or naval use, and if any such lease is so made, the provisions of any contracts or leases in conflict with the provisions of the lease to the government shall be suspended.
   B.   City Construction of Facilities: In the event the City constructs the physical plant facilities (hangars, etc.) for use by any lessee under the provisions of any lease or other contract, such lease or contract with such lessee shall be on such terms and conditions as to guarantee a full return of the investment to the City, plus interest and reasonable rental for use during such period.
   C.   Sublease:
      1.   No lessee shall sublease or sublet any premises leased by such lessee from the City, or assign any such lease without the prior written approval of the City.
      2.   In the event the lessee sublets any portion of his lease, the sublessee must agree to assume the full obligations of the lease as set out herein and must agree to fully cooperate with the City in seeing that these standards are complied with. The sublessee shall immediately comply with any reasonable request or direction of the City as it relates to the enforcement of these standards.
   D.   Default: In the event that the lessee or its sublessee fails to comply fully with these standards or fails to comply with the reasonable request or direction of the City as it relates to these standards, said operator or sublessee shall be in default. If said default continues for more than thirty (30) days after notice of said default, the City may terminate the lease. The operator is responsible for the performance of the sublease.