Weapons Delivery Principles And Procedures
Weapons
of sight will be below the ADL. The sight angle is set with the SET DEP rocker on the data entry
panel of the HUD.
Mil
An angular measure defined as 1/6400 of a circle. Sight angle is measured in mils. A mil is a
convenient unit of measurement because a mil subtends approximately one unit at one thousand
units. That is, if two lines spread apart with an angle of one mil, they will be one foot apart after
1,000 feet, two feet apart after 2,000 feet, and so on out.
Time of Fall
The length of time between release of a weapon and its impact with the ground. This is the time
during which gravity acts on the weapon to bend its trajectory below the aircraft line of flight.
FACTORS AFFECTING TRAJECTORY
For each type of weapons run you make, you will have a mil setting, which will compensate for the
extent to which a weapon will drop below your aircraft flight path. Each mil setting is calculated so
that if you release your weapon at the proper altitude, with correct airspeed, dive angle, and g, with
wings level, zero yaw, and the pipper on the target, the weapon will hit the target, assuming no wind.
However, a change in any of these parameters will affect the trajectory of the weapon. The effect of
changing each parameter will now be considered. The following factors are discussed from a
perspective of using a Depressed Sight Line (DSL) pipper in the T-45C manual (MAN) bombing
mode.
Release Altitude
Releasing high will increase the time of fall of the weapon, and so will increase the time during which
gravity can act to bend its trajectory. You are also releasing a greater distance from the target.
Therefore, if you release high, with all other parameters correct, the weapon will hit short. Similarly,
if you release low, the hit will be long.
Release Airspeed
Any deviation from planned release airspeed will cause a false sight picture. For example, a fast
release will decrease your AOA and bring the pipper short of the impact point causing a long hit. A
slow release will show the pipper long and cause a short hit. Airspeed also has an effect on the
weapon time of fall.
Dive Angle
Deviations from planned dive angle will also cause a false sight picture. A steep dive will cause a
long hit and a shallow dive a short one. Changing the dive angle will change the extent to which
gravity will bend the weapon trajectory below the line of flight. Suppose you release a weapon at a
dive angle of 90 degrees. Since gravity works straight down, there will be no effect on the trajectory.
You can see that a steeper angle requires a smaller mil setting; if you release steep, your mil setting
is too large and the bomb will strike beyond the target. If you are shallow, you need a greater mil
setting, just as you do for a shallow pattern, and your hit will be short.
G at Release
Proper g at release depends on dive angle. For a 30-degree delivery, about 0.87 g is required to
maintain a straight flight path. A 10-degree dive requires almost 1 g. A 60-degree dive (not used in
the training command) would require only 0.5 g. The mil setting for each type of delivery is valid only
at the proper g. Incorrect g at release will change the angle of attack of the ADL and will invalidate
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