NAVWEPS DO-ROT-80 
APPLICATION OF AERODYNAMICS 
TO SPECIFIC PROBLEMS OF FLYING 
RC,,= 33,ooo pa;pr ( 1 
where 
RC=rate of climb, ft: per min. 
Pn=propulsive power available, h.p. 
Pr=power required for level flight, h.p. 
W=gross weight, Ibs. 
From this relationship it is appreciated that 
the rate of climb in steady flight is a direct 
function of the difference between power avail- 
able and power required. If a given airplane 
configuration is in lift-equal-to-weight flight 
at some specific airspeed and altitude, there 
is a specific power required to maintain these 
conditions. If the power available from the 
powerplant is adjusted LO equal the power 
required, the rate of cl&b is zero (Pa--Pr=O). 
This is illustrated in figure 6.1 where the power 
available is ser equal to the power required at 
velocity (A). If rhe airplane were in steady 
level flight at velocity (A), an increase in 
power available would create an excess of 
power which will cause a rate of climb. Of 
course, if the speed were allowed to increase 
by a decreased angle of attack, the increased 
power setting could simply maintain altitude 
at some higher airspeed. However, if the 
original aerodynamic conditions arc maintain- 
ed, speed is maintained at (A) and an increased 
power available results in a rate of climb. 
Also, a decrease in power available at point (A) 
will produce a deficiency in power and result 
in a negative rate of climb (or a rate of descent). 
For this reason, it is apparenr. that pomr 
setting is the primary control of altitude in Jtcady 
Bight. There is the direct correlation between 
the excess power (Pa-P,>, and rhe airplane 
rate of climb, RC. 
FLYING TECHNIQUE, Since the condi- 
tions of steady flight predominate during a 
majority of all flying, the fundamentals of 
flying technique are the principles of steady 
flight: 
(1) Angle of attack is the primary control 
of airspeed. 
(2) Power setting is the primary control 
of altitude, i.e., rate of cl&b/descent. 
With the exception of the transient conditions 
of flight which occur during maneuvers and 
acrobatics, the conditions of steady flight will 
be applicable during such steady flight condi- 
tions as cruise, climb, descent, takeoff, ap- 
proach, landing, etc. A clear understanding 
of these two principles will develop good, safe 
flying techniques applicable to any sort of 
airplane. 
The primary control of airspeed during 
steady flight conditions is the angle of attack. 
However, changes in airspeed will necessitate 
changes in power setting to maintain altitude 
because of the variation of power required with 
velocity. The primary control of altitude 
(rate of climb/descent) is the power setting. 
If an airplane is being flown at a particular 
airspeed in level flight, an increase or decrease 
in power setting will result in a rate of climb 
or descent at this airspeed. While the angle 
of attack must be maintained to hold airspeed 
in steady flight, a change in power setting will 
necessitate a change in nttitude;to.accommodate 
the new flight path direction. These princi- 
ples form the basis for “attitude” flying tech- 
nique, i.e., “attitude plus, power equals per- 
formance,” and provide .a background for 
good instrument flying technique as well as 
good flying technique for all ordinary flying 
conditions. 
One of the most important phases of flight 
is the landing approach and it is during this 
phase of flight that the principles of steady 
flight are so applicable. If, during the landing 
approach, it is realized that ithe airplane is 
below the desired glide path, an increase in 
nose up attitude will not insure that the 
airplane will climb to the desired glide path. 
In fact, an increase in nose-up attitude may 
produce a greater race of descent and cause 
the airplane co sink more below the desired 
glide path. At a given airspeed, only an 
increase in power setting can cause a rate of 
climb (or lower rate of descent) and an in- 
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