Defense against UAV's

"Arved Sandstrom" wrote:

:"Fred J. McCall" wrote in message
.. .
:[ SNIP ]
: I learned it the simple way: If you can see it, you can kill it.
:
:Well, not if "it" is capering about merrily in a No Fire Area.

I can't say I believe in No Fire Areas.

--
"You'd see his work everywhere but never see him. A
colonel in Special Ops said he was the ******* son
of Clint Eastwood and Yoda."
-- Colby Granger, "Numb3rs"

"William Black" wrote:

:Underestimating an enemy, or potential enemy, is a very dangerous thing to
:do.

So is overestimating one and acting on that. Just think how much
money you could spend to counter Potemkin Villages....

--
"Millions for defense, but not one cent for tribute."
-- Charles Pinckney

writes:

rb wrote:

Highly unlikely that it went undetected for 25 mins.
More likely it's Iranian sabre rattling again.

Regardless of the accuracy of this particular account, it is true that
UAVs pose a new problem for navies and armies, especially in the
smaller versions. Defensive systems are generally designed to detect
and destroy much bigger and more obvious targets, and even if they
manage to spot a small UAV, what would be used to shoot it down?

This is the subject of much debate at the moment. Ordinary homing
missiles may not be able to lock-on to a stealthy little UAV (and even
if they could, there's not much logic in using a very expensive missile
to shoot down a very cheap plane). A radar-directed gun system like
Phalanx might also not lock-on to such a target. The best bet at the
moment IMO would be a 35mm gun firing the Oerlikon AHEAD 'shrapnel'
type airburst ammo, using electro-optical guidance.

At the end of the day, a smaller and more mobile target will win the
inevitable arms race: as yet un- or under-developed weapons for such a
small vehicle will be able to compromise (either individually or in
numbers) a much larger surface warship, leading to the realization
that warship-based gun development is just postponing the
inevitable. A rational multi-layered solution would require one's own
similarly-sized (and priced) vehicles capable of taking out the other
sides', methods to reduce the capability to launch (=airfield or
controller suppression) and to control. There is no chance of
preventing countries from producing or deploying such weapons, since
that is normal sovereign behaviour.
--
Gernot Hassenpflug ) Tel: +81 774 38-3866
JSPS Fellow (Rm.403, RISH, Kyoto Uni.) Fax: +81 774 31-8463
http://www.rish.kyoto-u.ac.jp/radar-...members/gernot Mob: +81 90 39493924

wrote:
rb wrote:
The US navy in particular seems to have seen the writing on the wall for
some time now, hence (I would assume) part of the reason for their
interest in developing the 'Millenium' gun and expressed interest in the
naval 57mm cannon.
http://www.lockheedmartin.com/wms/fi...=400&jsi=false
http://www.navyleague.org/sea_power/dec_04_46.php

The 35mm Millennium gun would qualify - that's designed to fire the
AHEAD ammo I mentioned - but I'm not so sure about the Bofors 57mm. In
the AA mode that uses radar aiming and proximity fuzes, and I'm not
sure if either would be sensitive enough to respond to a small stealthy
UAV.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk


3P ammunition should work with time fusing at least, so long as the uav
can be targetted...

http://www.naval-technology.com/cont...ssiles/bofors/
"...
SIX-MODE PROGRAMMABLE ALL-TARGET 3P AMMUNITION
The different function modes of the 3P ammunition gives Bofors Naval Gun
Systems the flexibility to combat a range of targets:

Gated Proximity Function, Gated Proximity Function with Impact Priority
and Conventional Proximity Function for Air Defence
Time Function for combating small, fast, manoeuvring surface targets and
concealed on-shore targets
Impact Function and Armour Piercing Function ..."

http://www.uniteddefense.com/prod/ngun_mk3.htm

"....The 57mm Mk 3 provides unmatched lethality with multiple 57mm
ammunition options available from the weapon's twin compartment magazine
that can shift between round types instantly. Bofors 57mm 3P all-target
programmable ammunition allows three proximity fuzing options as well as
settings for time, impact and armor-piercing functions. With a range of
17 kilometers, Bofors 57mm HCER surface target ammunition provides reach
and explosive effect comparable to larger caliber guns...."


rb

In article %AMfg.1638$I61.24@clgrps13,
says...
wrote:
Ken Chaddock wrote:


Block 1B CIWS has an infrared and optical tracker that would do nicely
against any UAV within it's range...the question is finding the UAV in
the first place. An Infrared search system with the ability to designate
to a B1B Phalanx would work quite well I think...


But a prop-driven UAV with a small engine and some attention to exhaust
masking would not be an easy IR target.

If all you want to do is locate and identify a ship, and beam an
illuminating laser at it to guide the incoming ordnance, then the UAV
can be very small and very hard to detect.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk

Have you ever seen the radar return from a prop ? Looks like a bloody
747...a prop-job wouldn't be a particular problem and contrary to
popular misconception, most modern IR trackers don't rely on a hugh heat
gradient but rather on the difference in emissivity between the target
and the background, IOW it's tracking the delta, not the absolute IR
output of the target...

So what IS the radar return from a wooden or fiberglass propellor like?

The UAVs that I've seen and the powered paragliders don't have metal
propellors. I suspect the reason is economics, rather than stealth,
though.



Mark Borgerson

In article ,
says...
wrote:

:
:Fred J. McCall wrote:
: wrote:
:
: : Hint #3: A fighter with a 20mm Vulcan will flat mess up a "small,
: : slow UAV" and actually has a radar on board so that he can see it and
: : some actual training on how to do an air intercept, neither of which a
: : helicopter has.
: :
: :Always assuming that the radar is capable of getting a lock on the UAV.
:
: No such assumption is necessary. It's not like in the movies.
:
:What makes you so certain that gunnery radar WILL lock on to a stealthy
:UAV?

What makes you think that fighter aircraft use gunnery radar?

:The UAVs are designed, after all, to avoid being picked up by
:radar. For defence planning purposes the assumption has to be that
:radar will not probably work against them, unless and until it is
roved to be capable of doing so. To take any other attitude would be
:foolish complacency.

Which means nothing, since a fighter attacking with a gun uses
EYEBALLS to get the target and they're way up close.

: :If not, his chance of scoring a hit is remote - the speed differential
: :is so huge that he could do no more than 'spray and pray'.
:
: Hint #1: What do you think the landing speed of a jet fighter is?
:
: Hint #2: Guns work off the pilot's eyeballs.
:
:And exactly how will the pilot aim his guns, if the radar gunsight
:won't lock on and the sights he's got are no better than WW2 standards?

He'll aim them the same way he aims them against anything else. Times
have changed since WW2 and no 'radar gunsight' is required.

:Hint #1: in WW2 the Luftwaffe found that only between 2% and 5% of the
:shots they fired hit the target - and they were shooting at B-17s! Now
:scale down the target size to a UAV with a wingspan of a couple of
:metres, and work out how much ammo would have to be fired to nail one.

About 5 rounds.

Hmmm, coming up behind a UAV with a 6-foot wingspan, the cross-sectional
area of the target might be only 1 or 2 square feet. How close does
the fighter pilot have to be to hit a 2 square foot target with 5
rounds?

:Hint #2: unlike the Luftwaffe's ammo, the current standard US 20mm
:aircraft SAPHEI shell, the PGU-28/B, does not have a tracer - so the
ilot will have no idea where his shots are going.

Nor does he need to. It's NICE to have radar, but it's hardly
necessary in order to score a lot of hits with a modern gun and HUD.
SNIP

Mark Borgerson

Fred J. McCall wrote:

A load of BS.

Well done, you've managed the rare achievement of being put on my
IGNORE list as not worth reading or responding to.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk

Mark Borgerson mborgerson.at.comcast.net wrote:

:In article ,
says...
: wrote:
:
: :
: :Fred J. McCall wrote:
: : wrote:
: :
: : : Hint #3: A fighter with a 20mm Vulcan will flat mess up a "small,
: : : slow UAV" and actually has a radar on board so that he can see it and
: : : some actual training on how to do an air intercept, neither of which a
: : : helicopter has.
: : :
: : :Always assuming that the radar is capable of getting a lock on the UAV.
: :
: : No such assumption is necessary. It's not like in the movies.
: :
: :What makes you so certain that gunnery radar WILL lock on to a stealthy
: :UAV?
:
: What makes you think that fighter aircraft use gunnery radar?
:
: :The UAVs are designed, after all, to avoid being picked up by
: :radar. For defence planning purposes the assumption has to be that
: :radar will not probably work against them, unless and until it is
: roved to be capable of doing so. To take any other attitude would be
: :foolish complacency.
:
: Which means nothing, since a fighter attacking with a gun uses
: EYEBALLS to get the target and they're way up close.
:
: : :If not, his chance of scoring a hit is remote - the speed differential
: : :is so huge that he could do no more than 'spray and pray'.
: :
: : Hint #1: What do you think the landing speed of a jet fighter is?
: :
: : Hint #2: Guns work off the pilot's eyeballs.
: :
: :And exactly how will the pilot aim his guns, if the radar gunsight
: :won't lock on and the sights he's got are no better than WW2 standards?
:
: He'll aim them the same way he aims them against anything else. Times
: have changed since WW2 and no 'radar gunsight' is required.
:
: :Hint #1: in WW2 the Luftwaffe found that only between 2% and 5% of the
: :shots they fired hit the target - and they were shooting at B-17s! Now
: :scale down the target size to a UAV with a wingspan of a couple of
: :metres, and work out how much ammo would have to be fired to nail one.
:
: About 5 rounds.
:
:Hmmm, coming up behind a UAV with a 6-foot wingspan, the cross-sectional
:area of the target might be only 1 or 2 square feet. How close does
:the fighter pilot have to be to hit a 2 square foot target with 5
:rounds?

He doesn't have to hit it with 5 rounds. He has to hit it with 1
round out of 5.

This is probably not that difficult from hundreds of yards away. The
HUD shows him what the bullet path is going to be. Initially they'll
probably get FAR too close until they realize how small the targets
are.

--
"Death is my gift." -- Buffy, the Vampire Slayer

wrote:

:Fred J. McCall wrote:
:
:A load of BS.
:
:Well done, you've managed the rare achievement of being put on my
:IGNORE list as not worth reading or responding to.

How nice. And so you demonstrate your allergy to the truth.

Which fact was it demolishing your case that put you over the edge?

snicker

--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn

In message .com,
writes
Paul J. Adam wrote:
Stealth aircraft aren't generally trying to play Kamikaze into warships
at sea.

True, but I have been thinking more in terms of getting no closer than
is required to identify the target and illuminate it with a laser.

That's still "close range" compared to expected radar performance.

For
a ship near to the shore, you could that with a very small UAV, I
think: not easy to knock down, even if you're able to detect it.

Not *that* small - the designator (with enough power to work at a decent
standoff), the optics to know where it's pointed, the transmitter with
enough bandwidth to allow effective search, identification and
engagemenrt, the stabilisation system for all this to make it usable and
the power supply to keep it all running add up to a pretty sizeable
package.

A current system gets you about 11kg for a portable laser designator,
with a range of 5km quoted. That's pretty close quarters...

http://www.dsd.es.northropgrumman.co...laser/LLDR.pdf


Another handy site is www.flir.com - they make some good kit and their
brochures demonstrate how going from simple optical/TI to adding
designation capability, range unspecified, ramps your payload weight
from 13 to 51 kilograms (compare their Microstar II to the BRITE Star)


Perfectly feasible to pack all these systems into a UAV and have them
work very well (see Predator) but it does impose a size penalty, and
also increases the effort needed if as well as working and flying you
have to add "and very low RCS across all the frequencies of interest".

Not that much smaller than some more conventional antiship threats, in
fact

--
Paul J. Adam