acceleration during this phase of the takeoff and climb.  Airspeed, altitude, climb rate, attitude, and heading must  be monitored carefully. When the airplane settles down to a  steady climb, longitudinal stick forces can be trimmed out.  If a turn must be made during this phase of flight, no more  than 15° to 20° of bank should be used. Because of spiral  instability and, because at this point an accurate trim state  on rudder and ailerons has not yet been achieved, the bank  angle should be carefully monitored throughout the turn. If  a power reduction must be made, pitch attitude should be  reduced simultaneously and the airplane monitored carefully  so as to preclude entry into an inadvertent descent. When  the airplane has attained a steady climb at the appropriate  en route climb speed, it can be trimmed about all axes and  the autopilot engaged. baseline landing distance on a dry, level runway at standard  temperatures without using thrust reversers, auto brakes, or  auto-land systems. In order to meet regulatory requirements  however, a safety margin of 67 percent is added to the  unfactored dry landing distance in the FAA-approved AFM,  after applicable adjustments are made for environmental and  aircraft conditions (MEL/CDL penalties). This corrected  length is then referred to as the factored dry-landing distance  or the minimum dry-landing field length.  [Figure 15-22]  For minimum wet-landing field length, the factored dry- landing distance is increased by an additional 15 percent.  Thus, the minimum dry runway field length is 1.67 times  the actual minimum air and ground distance needed, and the  wet runway minimum landing field length is 1.92 times the  minimum dry air and ground distance needed.  Certified landing field length requirements are computed for  the stop made with speed brakes deployed and maximum  wheel braking. Reverse thrust is not used in establishing  the certified landing distances; however, reversers should  definitely be used in service. The FAA landing field length requirements for jet airplanes  are specified in 14 CFR part 25. It defines the minimum  field length (and therefore minimum margins) that can be  scheduled. The regulation describes the landing profile as the  horizontal distance required to land and come to a complete  stop on a dry surface runway from a point 50 feet above  the runway threshold, through the flare and touchdown,  using the maximum stopping capability of the aircraft. The  unfactored or certified landing distance is determined during  aircraft certification. As such, it may be different from the  actual landing distance because certification regulations do  not take into account all factors that could potentially affect  landing distance. The unfactored landing distance is the  As in the takeoff planning, there are certain speeds that must  be taken into consideration when landing a jet airplane. The  speeds are as follows: Figure 15-22.  FAR landing field length required. 15-25 • V$_{SO}$—stall speed in the landing configuration • V$_{REF}$—1.3 times the stall speed in the landing  configuration TD V$_{REF}$ = 1.3 V$_{S}$ Actual distance 60% FAR (dry) runway field length required 1.67 × actual distance 40% 50 ft 15% FAR (wet) runway field length required 1.15 × FAR (dry) or  1.92 × actual distance Jet Airplane Approach and Landing Landing Requirements Landing Speeds