From FAR Part 91:
§ 91.9 Civil aircraft flight manual, marking, and placard requirements.
(a) Except as provided in paragraph (d) of this section, no person may operate a civil aircraft without complying with the operating limitations specified in the approved Airplane or Rotorcraft Flight Manual, markings, and placards, or as otherwise prescribed by the certificating authority of the country of registry.
The approved Airplane Flight Manual, Chapter Limitations, contains the airworthiness limitations, which are the legal limits of validity of the Certificate of Airworthiness. Violation is against the law, except as provided in Part 91.
As stated in Part 91, the airworthiness limitations apply irrespective of the type of operation conducted. In addition to Part 91, there are operating regulations which apply for particular types of operations, e.g. Part 121 and Part 135.
For Large Transport Airplanes, the airworthiness limitations for performance include the takeoff and landing WAT limits, and the minimum distances required for takeoff: TOD, TOR and ASD. In addition to those, the AFM contains the performance data required
for complying with the operating rules specified in Part 121 and Part 135, e.g. landing distances and engine-out flight path data for takeoff, en-route,
and landing.
Regards,
HN39