doubt about proper flying techniques. For 
example, if the airplane is established at point 
B in level flight, a controlled increase in air- 
speed (by reducing angle of attack) without 
change in power setting will create an excess 
of power at the higher airspeed and cause the 
airplane to climb. Also, a controlled decrease 
in airspeed (by increasing angle of attack) 
without a change of power setting will create 
a deficiency of power at the lower airspeed 
and cause the airplane to descend. This rela- 
tionship should leave little doubt as to the 
primary control of airspeed and altitude. 
The transient conditions during the changes 
in airspeed in the region of reversed command 
are of interest from the standpoint of landing 
flare characteristics. Suppose the airplane is 
in steady flight at point B and the airplane 
angle of attack is increased to correspond with 
the value for the lower airspeed of point C (see 
fig. 6.2). The airplane would not instanta- 
neously dPvelop the lower speed and rate of 
descent common to point C but would approach 
the conditions of point C through some tran, 
sient process depending on the airplane char. 
acteristics. If the airplane characteristics are 
low wing loading, high L/D, and high lift curve 
slope, the increase in angle of attack at point B 
will produce a transient motion in which 
curvature of the flight path demonstrates a 
definite flare. That is, the increase in angle 
of attack creates a momentary rate of climb 
(or reduction of rate of descent) which would 
be accompanied by a gradual loss of airspeed. 
Of course, the speed eventually decreases to 
point C and the steady state rate of descent is 
achieved. If the airplane characteristics are 
high wing loading, low L/D, and low lift curve 
slope, the increase in angle of attack at point B 
may produce a transient motion in which the 
airplane does not flare. That is, the increase 
in angle of attack may produce such rapid re- 
duction of airspeed and increase in rate of 
descent that the airplane may be incapable of 
a flaring flight path without an increase in 
power setting. Such characteristics may neces- 
NAVWEPS 00-807-80 
APPLICATION OF AERODYNAMICS 
TO SPECIFIC PROBLEMS OF FLYING 
sitate special landing techniques, particularly 
in the case of a flameout landing. 
Operation in the region of reversed command 
does not imply that great control difficulty and 
dangerous conditions will exist. However, 
flight in the region of reversed command does 
amplify any errors of basic flying technique. 
Hence, proper flying technique and precise 
control of the airplane are most necessary in 
the region of reversed command. 
THE ANGLE OF ATTACK INDICATOR 
AND THE MIRROR LANDING SYSTEM 
The usual errors during the takeoff and 
landing phases of flight involve improper con- 
trol of airspeed and altitude along some desired 
flight path. Any errors of technique are ampli- 
fied when an adequate visual reference is not 
available to the pilot. It is necessary to 
provide the pilot with as complete as possible 
visual reference field to minimize or eliminate 
any errors in perception and orientation. The 
angle of attack indicator and the mirror land- 
ing system assist the pilot during the phases of 
takeoff and landing and allow more consistent, 
precise control of the airplane. 
THE A.NGLE OF ATTACK INDICATOR. 
Many specific aerodynamic conditions exist at 
particular angles of attack for the airplane. 
Generally, the conditions of stall, landing ap- 
proach, takeoff, range, endurance, etc., all 
occur at specific values of lift coefficient and 
specific airplane angles of attack. Thus, an 
instrument to indicate or relate airplane angle 
of attack would be a valuable reference to aid 
the pilot. 
When the airplane is at high angles of attack 
it becomes difficult to provide accurate indica- 
tion of airspeed because of the possibility of 
large position errors. In fact, for low aspect