14 C.F.R. § 121.551 Restriction or suspension of operation: Domestic and flag operations.
Title 14 - Aeronautics and Space
When a certificate holder conducting domestic or flag operations knows of conditions, including airport and runway conditions, that are a hazard to safe operations, it shall restrict or suspend operations until those conditions are corrected. [Doc. No. 28154, 61 FR 2613, Jan. 26, 1996]
Title 14: Aeronautics and Space
PART 121—OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS
Subpart T—Flight Operations
§ 121.551 Restriction or suspension of operation: Domestic and flag operations.

