text: where 
  
  RC=rate of climb, f.p.-. 
  P11=power available, h.p. 
  Pr=power re 
  uired, h.p. 
  W=weight, 1 % 
  s 
  V=true airspeed, knots 
  and 
  
  33,000 is the factor converting horsepower 
  to ft-lbs/min 
  
  101.3isthefactorconvertingknocstof.p.m. 
  
  The above relationship states that, for a given 
  weight airplane, the rate af climb (RC) depends 
  on the difference between the power available 
  and the power required (Pd- Pr), or excess 
  power. Of course, when the excess power is 
  or Pa== PI), the rate of climb 
  zero (Pa-Pr=O 
  is zero and the airplane is in steady level flight. 
  When the power available is greater than the 
  power required, the excess power will, allow a 
  rate of climb specific to the magnitude of excess 
  power. Also, when the power available is 
  less than the power required, the deficiency of 
  power produces a rate of descent. This rela- 
  tionship provides the basis for an important 
  axiom of flight technique: “For the conditions 
  of steady flight, 
  the power setting is the pri- 
  mary control of rate of climb or descent”. 