e.g., cruise, climb, maneuvers, etc. The region 
of reversed command is encountered primarily 
in the low speed phases of flight during takeoff 
and landing. Because of the extensive low 
speed flight during carrier operations, the 
Naval Aviator will be more familiar with the 
region of reversed command than the ordinary 
pilot. 
The characteristics of flight in the region’of 
normal command are illustrated at point A on 
the second curve of figure 6.2. If the airplane 
is established in steady, level flight at point A, 
lift is equal to weight and the power available 
is set equal to the power required. When the 
airplane is disturbed to some airspeed slightly 
greater than point ‘A, a power deficiency exists 
and, wheq,:the &+la&is disturbed to some air- 
speed slightly lower than point A, a power 
excess exists. This relationship provides a 
tendency for the airplane to return to the equili- 
brium of point A and resume the original flight 
condition following a disturbance. Also, the 
static longitudinal stability of the airplane 
tends to return the airplane to the original 
trimmed CL and velocity corresponding to this 
C,. The phugoid usually has most satisfactory 
qualities at low values of C,. so the high speed 
of the region ‘of normal command provides 
little tendency of. the airplane’s, airspeed to 
vary or wander abom. 
With all factors considered, flight in Lhe 
region of noi& command is characterized by 
a relatively strong tendency of the airplane to 
maintain the trim speed quite naturally. How- 
ever, flight in the region of normal command 
can lead to some unusual and erroneous impres-, 
sions regarding proper flying technique. For 
example, if the airplane is established at point 
A in steady level flight, a controlled increase in 
airspeed without a change in power setting 
will create a deficiency of power and cause the 
airplane to descend. Similarly, a controlled 
decrease in airspeed without a change in power 
setting will create an excess of power and cause 
the airplane to climb. This fact, coupled with 
Lhe transient motion of the airplane when the 
NAVWEPS OD4OT-80 
APPLICATION OF AERODYNAMICS 
TO SPECIFIC PROBLEMS OF FLYING 
angle of attack is changed rapidly, may lead to 
the impression thal rate of climb and descent 
can be controlled by changes in angle of attack. 
While such is true in the region of normal com- 
mand, for the conditions of stead’ flight, pri- 
mary control of altitude remains the power 
setting and the primary control of airspeed re- 
mains the angle of attack. The impressions 
and habits that can be developed in the region 
of normal command can bring about disastrous 
consequences in the region of reversed com- 
mand 
The characteristics of flight in the region of 
reversed command are illustrated at point B 
on the second curve of figure 6.2. If the air- 
plane is established in steady, level flight at 
point B, lift is equal to weight and the power 
available is set equal to the. power required. 
When the airplane is disturbed to some air- 
speed slightly greater than point B, an excess 
of power exists and, when the airplane is dis- 
turbed to some airspeed slightly lower than 
point B, a deficiency of power exists. This 
relationship is basically unstable because the 
variation of excess power to either side of 
point B tends to magnify any original dis- 
turbance. While the static longitudinal sta- 
bility of the airplane tends to maintain the 
original trimmed C, and airspeed correspond- 
ing to that CL, the phugoid usually has the 
least satisfactory qualities at the high values 
of CL corresponding to low speed flight. 
When all factors are considered, flight in the 
region of reversed command is characterized 
by a relatively weak tendency of the airplane 
to maintain the trim speed naturally. In fact 
it is likely that the airplane will exhibit no 
inherent tendency to maintain the trim speed 
in this regime of flight. For this reason, the