FIGURE 3. V-1 Drawing.
ings and closings, along with the series
of explosions, caused the feared ‘buzz.’
I’ve heard model airplane pulse jets
operate and can see why they have been
banned in most populated areas; they
sound a lot like a blaring horn. Much like
the landing of a mosquito in a tent at
night; the worry came when the V-1’s
buzz stopped. It proved to be the world’s
first operational cruise missile with it very
unique guidance system (Figure 3).
The V-1 was launched from a steam
catapult (much the same as today’s Navy
planes launch from an aircraft carrier)
and could reach speeds of over 580 km
per hour. The V-1 was equipped with an
automatic pilot that utilized a magnetic
compass. Three compressed air-driven
gyrocompasses were also used in the
system. A master gyro controlled the
pitch and roll through rudder and elevator surfaces by an air-driven servo system
with corrections fed into the system by
the magnetic compass. A weighted pendulum interconnected with the magnetic
compass acted as a fore and aft attitude
sensor, as well as an accelerometer. This
ingenuous arrangement allowed simple
turns to be accomplished by using only
rudder control and no ailerons were
required for banking.
The other two gyros damped out
errors and oscillations in the
flight. Prior to launch, the V-1
crew would pre-set controls
for the required height and
direction of flight, as well as
distance to their target. A vane
anemometer (in reality, a small
propeller in the nose of the V-
1) turned so many revolutions
according to speed and distance traveled and acted like
an odometer to tell the system
how far the missile had
traveled towards its target.
These turns unwound a preset
mechanical counter that would throw
the V-1 into a steep dive at the target
area by causing the elevator to depress.
Would you believe that they actually
used a tiny guillotine triggered by the
counter to sever the air hose feeding the
elevator, causing it to depress? I would
have thought that a small valve would
have done a better job. This abrupt dive
angle caused the fuel to stop flowing to
the engine in the early models, thus stopping the buzz, and the British knew a V-
1 was soon to strike. Later models powered themselves all the way to the target. Almost 12,000 V-1s were launched
against Britain, though only about 25%
actually hit significant targets.
The Unmanned Aerial
Vehicles of Today
FIGURE 4. Micro UAV.
There is as much difference in the
UAVs of today compared to Low’s and
the Nazi’s creations as to the Wright
Brother’s plane and the Boeing 787.
Endurance, range, speed, sophistication of sensors, autonomy and, of
course, cost have all spiraled upward.
There are two basic classes of
unmanned aerial vehicles. The first is the
classic combat weapon — the cruise missile. One example is the Tomahawk, the
workhorse of the Navy. This sophisticated
cruise missile proved itself in the Gulf War
of 1991 when it was programmed to find
its way from the submerged submarine
that launched it, all the way to downtown
Baghdad. News reporters were amazed
to see it fly down a street and make a
right turn to head to its final target. These
weapons are like flying torpedoes; their
purpose is to explode and destroy an
intended target and never return home.
Some people may even include the
unpowered smart bombs in this category. They are dropped from a plane, miles
from a target, and guide themselves
through varying control surfaces to a target that is illuminated by a laser beam.
This beam can be from an overhead
plane or from a soldier on the ground.
Another part of the combat
category is the target and decoy missile
that provides ground and aerial
gunnery a target that simulates a real
enemy aircraft or missile.
The second type of UAV includes the
aerial scout such as the Predator, an AUV
that returns to its home base. These
vehicles can be autonomous or remotely
controlled. The control can be from something as simple as a suitcase-sized console
used by a single ground soldier or as complex as a trailer with several controllers.
These AUVs are not weapons in
themselves, but can be loaded with small
missiles or bombs and be fired or
dropped by remote command. Most of
this category, however, is relegated to
passive spying or surveillance tasks. These
can be reconnaissance AUVs that provide
battlefield intelligence. There are also
UAVs specifically designed for cargo and
logistics operation. Government agencies
use UAVs for research and development
to further develop UAV technology.
There are so many variants of UAVs
today that they can range from tiny vehicles under one ounce in weight to vehicles weighing many tons. Figure 4 shows
a tiny AUV not much larger than a dragonfly, and there are operational vehicles
even smaller. Figure 5 shows a member
of the military hand-launching a vehicle
that contains a video feedback system
that it about the size of a typical R/C
model airplane. It is known as the Small
Unmanned Aerial Vehicles Advanced
Concept Technology Demonstration
(SUAV ACTD). These small AUVs bring
battlefield awareness to small unit
commanders. AUVs such as this can
cover many miles in distance, and more
importantly, send back images of many
square miles of terrain without risking
military personnel to hostile action.
The Navy’s Cruise
Governments around the world
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