With combat
operations winding down in Afghanistan, the U.S. Army is cutting back on
purchases of its popular RQ-11B Raven micro-UAV. In the last decade the
U.S. has bought most of the 19,000 Ravens produced. But now those
purchases are fading to zero. Last year the army bought 1,134, this year
it was 234 and next year it is zero. The reason why the army has bought
so many Ravens is because this tiny (two kg/3.3 pound) rapidly wears
out in combat. The Raven is made of Kevlar, the same material used in
helmets and protective vests, but there are many ways for one to be lost
in combat. On paper a Raven can survive about 200 landings before it
can no longer be used. That’s in peacetime operations. In a combat zone
few Ravens make it past fifty or so landings. While some Ravens have
been shot down, the most common cause of loss is a problem with the
communications link (as the aircraft flies out of range or behind
something that interrupts the signal) or a software/hardware failure on
the aircraft. Combat losses have been high, as nearly 20,000 have been
built and most of those have been lost on the battlefield.
With much less combat expected in the next few years, the army
is cutting orders for new Ravens and, in effect, living off existing
stocks (over 5,000 Ravens) and resuming purchases only if a lot of
troops are sent into combat. Raven, in effect, is being treated like
ammunition, with much needed in peacetime than in wartime.
Despite the high loss rate the Raven is popular with combat
and non-combat troops alike. In part this is because the army has
developed better training methods, which enables operators to get more
out of Raven more quickly. Combat troops use it for finding and tracking
the enemy, while non-combat troops use it for security (guarding bases
or convoys). In both cases troops have come to use the Raven for more
than just getting a look over the hill or around the corner. The
distinctive noise of a Raven overhead is very unpopular with the enemy
below and is often used to scare the enemy away or make him move to
where he can be more easily spotted.
The current model, the Raven B (RQ-11B), was introduced six
years ago, a year after the original Raven entered service in large
numbers. This UAV is inexpensive ($35,000 each). The Raven is battery
powered (and largely silent unless flown close to the ground). It
carries a color day vidcam or a two color infrared night camera. It can
also carry a laser designator and a new gimbaled camera is being bought.
The cameras broadcast real time video back to the operator, who
controls the Raven via a handheld controller, which uses a hood to
shield the display from direct sunlight (thus allowing the operator to
clearly see what is on the ground). The Raven can go as fast as 95
kilometers an hour but usually cruises at between 40 and 50 kilometers
an hour. It can go as far as 15 kilometers from its controller and
usually flies a pre-programmed route, using GPS for navigation.
From the very beginning the Raven changed the way troops
fight. With the bird's eye view of the battlefield, commanders can move
their troops more quickly, confident that they won't be ambushed and
often with certain knowledge of where the unseen enemy is. The big
advantage with Raven is that it’s simple, reliable, and it just works.
The UAV can be quickly taken apart and put into a backpack. It takes off
by having the operator start the motor and then throwing it. This can
be done from a moving vehicle and the Raven is a popular recon tool for
convoys. It lands by coming in low and then turning the motor off.
Special Forces troops like to use it at night because the enemy can’t
see it and often can’t hear it either.
Last year the U.S. Army began using the larger (5.9 kg) Puma
AE UAVs. Adopting Puma is part of an army effort to find micro-UAVs that
are more effective than current models and just as easy to use. The
Puma, a 5.9 kg (13 pound) UAV with a 2.6 meter (8.5 feet) wingspan and a
range of 15 kilometers from the operator, has proved to be the next big
(or micro) thing the army was looking for. Combat commanders quickly
realized how useful Puma is and wanted more, as quickly as possible.
This is not surprising as SOCOM (Special Operations Command) has been
using Puma since 2008.
The army wants to equip each infantry company with a Puma
system. That would mean 18 Puma AE UAVs per brigade and nearly 400 for
the entire army. These larger UAVs have been most useful in route
clearance (scouting ahead to spot ambushes, roadside bombs, landslides,
washouts, or whatever). The larger Puma is particularly useful in
Afghanistan, which is windier than Iraq and thus more difficult for the
tiny Raven to operate.
Top speed for Puma is 87 kilometers an hour and cruising speed
is 37-50 kilometers an hour. Max altitude is 3,800 meters (12,500
feet). Puma has a better vidcam (providing tilt, pan, and zoom) than the
smaller Raven and that provides steadier and more detailed pictures.
Because it is larger than Raven, and three times as heavy, Puma is much
steadier in bad weather. Both Puma and Raven are battery powered.
Puma has been around for a decade but never got purchased in
large quantities by anyone. The latest model uses a lot of proven tech
from the Raven (both UAVs are made by the same company). Like the Raven,
Puma is hand launched and can be quickly snapped together or apart.
Another version, using a fuel cell, has been tested and was able to stay
in the air for nine hours at a time. There is also a naval version that
floats and is built to withstand exposure to salt water.
Each combat brigade is now supposed to have 35 mini-UAV
systems (each with three UAVs, most of them Raven but at least ten of
these systems are to be Pumas). That means that each combat brigade now
has its own air force of over a hundred reconnaissance aircraft.
The army currently has nearly 7,000 UAVs. Over 6,000 are
micro-UAVs like the Raven and Puma. These tiny (under six kg/13.2 pound)
reconnaissance aircraft have become very popular with the troops,
anyone of which can become an operator after a few hours of training.
These tiny UAVs are a radical new military aircraft technology that took
air recon to a new level. That level is low, a few hundred meters off
the ground. The army has nearly 1,798 Raven and 325 Puma UAV systems in
use by ground troops. A complete system (controller, spare parts, and
three UAVs) costs $250,000 for the Raven and over $400,000 for Puma.
These tiny aircraft have changed how the troops fight and greatly
reduced army dependence on the air force for air reconnaissance. The
lightweight, hand launched Raven UAV can only stay airborne about an
hour per sortie, but troops have found that this is enough time to do
all sorts of useful work, even when there's no fighting going on. This
is most of the time. The heavier Puma can stay up for 120 minutes.
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