Introduction  Importance of Performance Data  This chapter discusses the factors that affect aircraft  performance, which include the aircraft weight, atmospheric  conditions, runway environment, and the fundamental  physical laws governing the forces acting on an aircraft.  The performance or operational information section of the  Aircraft Flight Manual/Pilot’s Operating Handbook (AFM/  POH) contains the operating data for the aircraft; that is, the  data pertaining to takeoff, climb, range, endurance, descent,  and landing. The use of this data in flying operations is  mandatory for safe and efficient operation. Considerable  knowledge and familiarity of the aircraft can be gained by  studying this material.  Chapter 11  Aircraft  Performance 