Weapons Delivery Principles and Procedures
Weapons
Corrections for Deflection
If your pipper is offset to one side of the desired initial aimpoint, the correction you can make for this
deflection error depends on the type of ordnance being used. With bombs, there is no last-minute
correction for deflection. Kicking in rudder to move the pipper to the desired aimpoint will
not appreciably affect the trajectory of the bomb, and your hit will not be improved. Rolling into an
angle of bank at the last moment will not be effective either, because the pendulum effect will cause a
false sight picture. You must recognize the problem early in the run, make a correction using small
amounts of bank, and be sure that your wings are level at release.
Conversely, with forward-firing ordnance, it is possible to use your rudder to make a last-minute correc-
tion for pipper deflection. Unlike bombs, forward-firing ordnance will initially travel in the direction it is
fired, even in unbalanced flight where the firing direction is not the same as the aircraft's direction of
flight. The ordnance will then curve as it aligns itself with the relative wind. Because of this realigning
tendency, you cannot simply move the pipper over to the desired aimpoint. You must make a larger
correction. With guns, because the bullets have a higher initial velocity and have less tendency to
align themselves with the relative wind, your correction should be 1.25 times the deflection error. For
example, if your pipper is 20 mils to the left of the desired aimpoint, use your rudder to move it a total of
25 mils to the right, so that it will be 5 mils to the right of the aimpoint.
Corrections for Multiple Errors
In each of the foregoing discussions of error correction techniques, it was assumed that only one dive
parameter was in error, and that the rest were correct. For example, when we say that a 2-degree error
in dive angle will cause a 100-ft miss, we are assuming that the weapon is released at the proper
airspeed and altitude, wings level, and with correct g and the pipper on the aimpoint. However, you will
frequently find that one or more of your dive parameters is in error as you approach release. In such a
case, the errors may be additive, or they may tend to cancel each other. For instance, suppose that in
a 30-degree bomb run, you notice that your dive angle is 1 degree shallow and that your airspeed is
10 kts slow. If you have learned your error sensitivities properly, you know that each of these errors will
cause your hit to be 50 ft short, for a total of 100 ft, and that you could correct by allowing the pipper to
drift 100 ft past the target by release altitude. On the other hand, if you happen to be 1 degree shallow
and 10 kts fast, you know that these errors cancel each other and no correction is needed. You can
probably see, however, that trying to mentally compute corrections for multiple errors during the few
seconds before release could become excessively complicated. Imagine trying to figure a correction
for steep dive angle, fast airspeed, and early sight picture. Remember that for now you are in a training
environment, and you have the option of aborting your run at any time. If you find yourself in a run that
is really fouled up, don't drop.
WIND CORRECTIONS
All of the procedures given up to this point have assumed that there was no wind. In most cases,
however, there will be a wind at release altitude, and you will have to make some slight changes in your
roll-in point, tracking procedure, and release point. As we mentioned, the primary effect of wind is to
change the aircraft's ground speed and direction. During the run, the motion of the aircraft relative to
the air mass is determined by the aircraft's airspeed and heading. At the same time, if the air mass is
drifting, the aircraft will drift with it and will impart this drift to the weapon at release. For example, if
your aircraft is drifting to the left at 20 ft per second (12 kts) when you release a bomb, then the bomb
will continue to drift left at 20 ft per second all the way to impact. If you release with the pipper on the
bull, with all your dive parameters correct, and if the time of fall of the bomb is 7 seconds, then your hit
will be 140 ft left of the target (7 X 20 = 140). Any change of wind between release and impact will
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