曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
while timing (typically 1-2 nautical miles) keeps this type of drop from being pinpoint accurate. Another
uses a beacon that interfaces with the aircraft's navigation computer and can automatically steer to the
CARP and release the load.
18.6.4.1. Weather Aerial Delivery System (AWADS). The adverse Weather Aerial Delivery System
(AWADS) can also be used. This system allows on-board radar updates to the computer, which is then
used to guide the aircraft to the CARP. Finally, more and more aircraft are being equipped with GPS
which can provide very accurate navigation to the CARP.
18.6.4.2. Station Keeping Equipment (SKE). You can also locate the release point using information
transmitted from another aircraft. In an IFR airdrop formation, the lead aircraft uses one of the above
methods to locate the release point. SKE-equipped follower aircraft time from signals transmitted by
lead to locate their respective release points.
18.7. Parachute Ballistics. The ballistics of different types of parachutes varies greatly. Each parachute
is designed for a specific purpose and has its own peculiar characteristics. The parachute ballistics used
in the solution of the CARP, for forward travel time and vertical distances, are averages that are accurate
enough to use on airdrops. One important characteristic of parachutes that cannot be computed in the
CARP solution is the gliding characteristics of each parachute. A parachute glides in random directions
during its descent and these directions tend to cancel out. If this were not the case, it would be extremely
difficult to obtain the desired accuracy, even if other variables (such as wind effect and aircraft
positioning) were negligible. For example, the T-10 parachute has a gliding angle of 18 degrees from the
vertical. This gliding effect is what makes parachutes appear to drift under no-wind conditions.
18.8. Components:
18.8.1. Vertical Distance. The distance, in feet, a load falls after exiting the aircraft and prior to
stabilization (Figure 18.4).
18.8.2. Rate of Fall. The rate of fall is the vertical velocity, in feet per second, of the airdropped load
while under full parachute canopy. Rate of fall is corrected to a standard day sea-level rate when
corrected for air density.
18.8.3. Time of Fall Constant (TFC). A constant in seconds computed during airdrop tests that
compensates for the nonlinear rate of fall from load exit to stabilization. This factor is used to determine
drift effect during stabilization (TFC = ST – DQ).
18.8.4. Forward Travel Time. Exit time plus deceleration quotient. A time constant that compensates
for the horizontal distance the object travels from the green light signal until reaching stabilization. This
factor is used to compute FTD.
AFPAM11-216 1 MARCH 2001 361
Figure 18.4. Horizontal View of the CARP.
18.8.5. Forward Travel Distance (FTD). The ground distance traveled by the airdropped load from the
green light signal to stabilization. Plot FTD back from the point-of-impact (PI) along DZ axis. Convert
the forward travel time in seconds to forward travel distance in yards (or meters) on the MB-4 using this
formula:
18.8.6. Drift Effect. Drift effect is the distance the parachute and load drift during the total time of fall.
This effect depends upon the total time of fall of the parachute load and the wind velocity. Compute drift
effect using the following procedures:
18.8.6.1. Find the time of fall by dividing the deployment altitude by the adjusted rate of fall to find the
number of seconds required for the parachute to descend from time of full deployment to the ground.
The parachute starts to drift as soon as it leaves the aircraft. Therefore, you should add the time of fall
constant to the time of fall to determine the total time of fall that is the number of seconds the load is
falling free of the aircraft and is affected by the wind.
18.8.6.2. Then multiply the total time of fall by the wind velocity to find the drift effect. The formula is:
18.8.7. Plotting CARP. The forward travel distance and drift effect have been discussed in the sequence
in which they occur; however, the CARP is plotted as follows:
362 AFPAM11-216 1 MARCH 2001
18.8.7.1. Starting from the point of impact, plot the drift effect upwind.
18.8.7.2. Plot the forward travel distance back along the DZ axis from the end of the wind vector. The
end of the forward travel vector is the CARP location (Figure 18.5).
Figure 18.5. CARP and DZ Diagram.
18.9. Summary. Bombing and airdropping use the same physical principles to accomplish the mission.
Both rely on a mathematical computation to determine the effect of wind and gravity on the bomb or
airdrop item. After compensating for that effect to locate the release point, both require pinpoint
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
F16 Flying Operations AIR NAVIGATION(147)
