Fighter Combat - Tactics and Maneuvering

416 APPENDIX
Figure A-22. Lift versus Angle of Attack
AOA. It is difficult to separate these two motions visually, so both are
generally included in "pitch rate." Once AOA has stabilized, pitch rate and
turn rate in a given maneuver plane are the same.
Pitch rate is important to fighters for several reasons. One of them is
that the faster AOA can be increased, the more quickly a turn can begin.
This can have a great effect on the early stages of maximum turnperformance
maneuvers. A second reason is the influence of pitch rate on
gunsight tracking. The ability simply to point the aircraft in a given
direction, regardless of its direction of motion, is quite valuable. A third
factor has to do with the difficulty of visually differentiating pitch rate
from turn rate. Since fighter pilots must rely on visual information to
assess the performance of an opponent's aircraft, large changes in AOA
easily may be mistaken for increased turn performance. Such a misinterpretation
often leads to mistakes in maneuver selection to counter the
perceived, maneuver of an adversary.
The pitch performance of a fighter, i.e., pitch rate and pitch acceleration,
is a function of the effectiveness of the pitch controls and the resistance the
aircraft presents to a pitching motion. The AOA contribution to pitch is
limited by the maximum usable AOA (stall AOA or limits of controllability)
at low speeds and by load-factor limits above corner speed. Since the
range of usable AOA is rather small (about 20° to 30°) for most fighters,
AOA's contribution to pitching motion is completed quickly. Therefore,
as in the case of roll performance, it is pitch acceleration rather than pitch
rate which is of greater importance in fighter maneuvering when the
discussion is limited to AOA changes only.
Since the rate of AOA increase is on the same order of magnitude as the
turn rate and is additive in producing total pitch performance, the greater
the range of usable AOA, the greater its contribution will be during the
early phases of a turn. Greatest pitch performance is often found near
corner speed, which provides the highest instantaneous turn rate and
represents the fastest possible speed (for maximum pitch-control authority)
at which the full range of AOA is available. Design features such as