http://www.maib.gov.uk/cms_resources...s%20report.pdf

Recommendations
· Based on the results of this report it is recommended that yachtsmen
always
fit a radar reflector that offers the largest RCS practicable for their
vessel.
· The RCS of the radar reflector should have a minimum consistent RCS of
2m2.
· The Sea-Me is the recommended product if power is available
· If power is not available then the passive Large Tri-Lens reflector is
recommended
· The 4” tube reflector is not considered suitable due to its poor
performance. It
is also recommended that the 2” tube reflector is not suitable since the
performance of this target will be even lower.
· It is recommended that poorly performing radar reflectors are not
fitted as it
is possible that the user could be lulled into a false sense of security
believing
that their chances of detection has been enhanced.

Someone sent this to me a few days ago and I was going to post it but you
beat me to it.

Wayne's reply to Skip's Look Out thread prompts this request to those in
this group who radar consistently:

The numbers in the British study aside, what do those of us in midsize
fiberglass sailboats generally look like to you in the real world? Do you
often see a boat with a radar reflector hanging that didn't show up on the
scope? Are we little blips that you could easily overlook? How would you
rate the chances of a vessel over running its visibility in fog not seeing a
radar reflector equipped boat?

--
Roger Long

On Sun, 12 Aug 2007 07:53:27 -0400, "Roger Long"
wrote:

The numbers in the British study aside, what do those of us in midsize
fiberglass sailboats generally look like to you in the real world? Do you
often see a boat with a radar reflector hanging that didn't show up on the
scope? Are we little blips that you could easily overlook? How would you
rate the chances of a vessel over running its visibility in fog not seeing a
radar reflector equipped boat?

Many, if not most, of the cruising sailboats I see offshore have some
sort of visible radar reflector. They typically show up very well at
4+ miles. I believe we'd see most of them without a reflector based
on my experience picking up small power boats.

We see a lot of 20 something fishing boats in near shore conditions,
invariably without any visible reflector. Most of them show up pretty
decently also. Larger cruisers and sportfish show up very well, most
without any sign of a reflector.

A lot depends on the radar however. My 26 year old backup system does
not do nearly as well and requires a good eye to separate targets from
the clutter. Digital technology has advanced a lot in that time and
it has made a big difference in my opinion.

Moonshadow wrote in news:46becafc$1_3
@news.chariot.net.au:

Based on the results of this report it is recommended that yachtsmen
always
fit a radar reflector that offers the largest RCS practicable for their
vessel.


http://www.shinemicro.com/RadarPlusSM162B.asp

Too bad some powerful entities are causing the FCC to drag its
bureaucratic feet on approval of this AIS TRANSPONDER that makes your
little sailboat look like an aircraft carrier, setting off all the
collision alarms on that 950' containership with the half-asleep seaman
at the helm, waking him up.

It will be most interesting to watch "them" telling the Admiralty Court
why they didn't have the Class B targets turned on on the ships REQUIRED
AIS system. It would seem that "We didn't see him.", the normal excuse
for being run down by the ships, now all AIS equipped, would be moot if
you had a real transponder firing away to the horizon.

If I were a ship owner or insurer, exposed for the lawsuits, I'd be
damned sure __ALL__ AIS targets would be displayed and acted upon on all
my ships. It makes good business sense.



These *******s keep calling me so I'm feeding them to the spambots.
--
Sunrise Communications
1374 E. Republic Rd.
Springfield, MO 65804
866-483-1228
417-886-7091
http://www.sunrisecommunicationsinc.com/
877-842-3210
866-842-3278
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....
Many, if not most, of the cruising sailboats I see offshore have some
sort of visible radar reflector. They typically show up very well at
4+ miles. I believe we'd see most of them without a reflector based
on my experience picking up small power boats.
....

Sea conditions play a huge role here. If there are small power boats
about you aren't at sea, you're near coastal. Over the last couple of
decades of voyaging and delivery work and through many bridge to
bridge communications I'd say that there is about a 50/50 chance that
a large ship that is looking for you will see a mid-sized cruising
boat with a radar reflector at four miles in anything less than ideal
conditions in the open ocean. It is extremely rare in my experience
for a ship to spot a small vessel offshore before being hailed. My
experience has largely been in the Pacific and in many cases in remote
parts of the Pacific and may not apply to the East Coast, but I think
it is worth keeping in mind that as the seas get large and the radar
less effective and the watches get less expectant of seeing vessels
and less diligent your chances of both seeing and being seen go way
down over what you might be used to in protected waters.

-- Tom.

"Roger Long" wrote in
:

The numbers in the British study aside, what do those of us in midsize
fiberglass sailboats generally look like to you in the real world? Do
you often see a boat with a radar reflector hanging that didn't show
up on the scope? Are we little blips that you could easily overlook?
How would you rate the chances of a vessel over running its visibility
in fog not seeing a radar reflector equipped boat?


I have a friend who is a ham radio operator and ship master of a 950'
SeaLand container ship. I asked him a similar question, so we went up on
his bridge and fired off the ships radar at the dock in downtown
Charleston, right in the harbor. It was Saturday and there were LOTS of
small boats/sailboats to target.....

The big radar antenna is, of course, way up on the mainmast probably
180' off the water, to the detriment of all the 50' radar reflectors it
shoots completely OVER within about a mile of the ship. The radar
antennas don't point down to avoid sea clutter mucking up the screens.
So, the radiated beam is restricted by a plate under it to limit downward
radiation. Once you're in the shadow of that plate, nothing will make
you "seen" by the radar operator....when it counts the most.

From the downtown dock on the seaward side of the Cooper River bridges,
the first detectable targets I could see were about even with Ft Sumter
on the OTHER side of the harbor. I used a really nice pair of stabilized
binoculars to visually spot what I could see on the screen and the
nearest target was a big sloop showing a radar reflector hanging under
his spreaders. The other targets moving around were past Ft Sumter out
in the ship channel. Even then, most of the sailboats never made a dot
on the screen with no reflector. The steel ships all made quite a blob,
even way out to our horizon. Some of the shrimp boats had a return
shrimping offshore.

Most of the plastic bubbleboats, even those 60' monsters barely showed up
unless they had a reflector, either.

This is all with the ship sitting perfectly upright and having a clear
view of the horizon on a clear day. From the bridge, I could see quite a
ways at sea out past the Jetties and offshore to the South over Noname
Island by Ft Sumter. I'm sure if your radar reflector were at 50' in 6'
seas, or worse, and the monster ship were rolling, you'd make even less
of an impressive blob than I saw.

If you ever get a chance to try it for yourselves, do light it off and
test your own theories. I sure wouldn't depend on the radar op seeing my
40' plastic boat at all, radar reflector or not. I think it's wishful
thinking and a LOT of luck.

Cap'n Larry told me to tell all my sailor friends that NOONE on his ship
is bothered, at all, if you CALL THEM ON CHANNEL 13 OR 16 TO LET THEM
KNOW YOU ARE THERE! I've always gotten a thank you from their bridge
after asking them if they see us crossing their path. Some did...many
didn't! Why sailors are so goddamned TIMID to talk to ships on the radio
has always been a mystery to me. Those guys on the bridge are BORED TO
TEARS! They're not busy, at all, as the ship drives itself. Especially
on the midwatch, I've spent hours talking to whatever mate is driving on
Channel 13 out beyond land. There's just you and him and you're not
jamming the dead channel at all.

I declined one mate's offer to swap Geoffrey's Endeavour 35 for a 450'
freighter full of bananas and fuel....(c; Both our captains were
asleep...hee hee. How many bananas can YOU eat?...(c; You'll find them
ALL very curious to know all about your boats. They've never been
sailing.







These *******s keep calling me so I'm feeding them to the spambots.
--
Sunrise Communications
1374 E. Republic Rd.
Springfield, MO 65804
866-483-1228
417-886-7091
http://www.sunrisecommunicationsinc.com/
877-842-3210
866-842-3278
United Healthcare
http://www.unitedhealthcareonline.com/

On Sun, 12 Aug 2007 11:34:21 -0700, "
wrote:

...
Many, if not most, of the cruising sailboats I see offshore have some
sort of visible radar reflector. They typically show up very well at
4+ miles. I believe we'd see most of them without a reflector based
on my experience picking up small power boats.
...

Sea conditions play a huge role here. If there are small power boats
about you aren't at sea, you're near coastal.

Agree on both counts. Most of the prior discussion relates to near
coastal cruising.

Over the last couple of
decades of voyaging and delivery work and through many bridge to
bridge communications I'd say that there is about a 50/50 chance that
a large ship that is looking for you will see a mid-sized cruising
boat with a radar reflector at four miles in anything less than ideal
conditions in the open ocean. It is extremely rare in my experience
for a ship to spot a small vessel offshore before being hailed.

My only experience with commercial vesels is in near coastal,
relatively calm conditions. I know that I have been spotted in those
circumstances, even with out a reflector. We're a bit bigger than the
average cruising sailboat however.

My
experience has largely been in the Pacific and in many cases in remote
parts of the Pacific and may not apply to the East Coast, but I think
it is worth keeping in mind that as the seas get large and the radar
less effective and the watches get less expectant of seeing vessels
and less diligent your chances of both seeing and being seen go way
down over what you might be used to in protected waters.


Makes sense unfortunately.

Larry wrote:

If you ever get a chance to try it for yourselves, do light it off and
test your own theories. I sure wouldn't depend on the radar op seeing my
40' plastic boat at all, radar reflector or not. I think it's wishful
thinking and a LOT of luck.

Aww crap Larry...now all I gotta do is find a genuine Homeland Security
approved active ECM critter and I'm good. Wonder how the Coasties and
Skimmers will feel about this...

In article ,
Larry wrote:

The big radar antenna is, of course, way up on the mainmast probably
180' off the water, to the detriment of all the 50' radar reflectors it
shoots completely OVER within about a mile of the ship. The radar
antennas don't point down to avoid sea clutter mucking up the screens.
So, the radiated beam is restricted by a plate under it to limit downward
radiation. Once you're in the shadow of that plate, nothing will make
you "seen" by the radar operator....when it counts the most.

Ahhh, Larry but you didn't gives us the most important piece of
information abut this "BIG" radar. Was it X-Band or S-Band?????
That will make a HUGH difference, in what Targets it paints, at
what distance....

ALL these 1500 Gross Ton or larger carry both......

Bruce in alaska
--
add a 2 before @

Bruce in Alaska wrote in news:bruceg-
:

Ahhh, Larry but you didn't gives us the most important piece of
information abut this "BIG" radar. Was it X-Band or S-Band?????
That will make a HUGH difference, in what Targets it paints, at
what distance....

ALL these 1500 Gross Ton or larger carry both......



Hmm...sorry. Standing at the odd-looking console watching targets with
Cap'n Larry I never asked. I never saw the transmitter, sorry.

I suppose my point is plastic boat sailors THINK the big guys can spot
them, on radar and visually. I suppose they COULD if we move the bridge
to the bow or take off all the containers in the way, but that isn't
gonna happen. The flag is 930' in front of the helm. You all know what
the genoa does to your ability to see those damned crabpot toilet floats
from your helm. Imagine if the obstruction were 900' FORWARD of your
bow! They can't really see anything less than a full sized ship, on
radar or out the windows. There are hardly any sailors aboard these huge
ships run by computers. The crews are, to increase profits, tiny in
respect to the size of the beast. There aren't 15 people with binoculars
standing on the bow, in a crow's nest looking out for icebergs and
Catalinas, guys standing on the bridge wings scanning the horizon for 4
hours like a Navy ship has. There's one guy, walking around the bridge,
bored to tears as the computer watches the GPS and flogs on towards
Holland....just like last week, last month, last year...
(yawn).....zzzzzZZZZ.





These *******s keep calling me so I'm feeding them to the spambots.
--
Sunrise Communications
1374 E. Republic Rd.
Springfield, MO 65804
866-483-1228
417-886-7091
http://www.sunrisecommunicationsinc.com/
877-842-3210
866-842-3278
United Healthcare
http://www.unitedhealthcareonline.com/