| Author |
Message |
    
Ted Lavino
Senior Member
Username: Tlavino
Post Number: 267
Registered: 01-2004
| | Posted on Sunday, May 01, 2005 - 10:10 pm: | 
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You can find more information regarding C.A.R.D at:
http://www.survivalsafety.com/.
Regards,
Ted |
Ralph Hollenberg (Unregistered Guest)
Unregistered guest
| | Posted on Wednesday, April 13, 2005 - 10:55 am: |
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Please help me in locating the vendor for a C.A.R.D (Collision Avaoidance Radar Detector} I have tried for some time but without succes. |
Ted Lavino
Senior Member
Username: Tlavino
Post Number: 186
Registered: 01-2004
| | Posted on Friday, June 18, 2004 - 12:39 pm: |
|
Greetings All, a great article from Ocean Navigator:
Topic: Communications/ Marine Electronics Issue No.: 41 Date: 06/18/04
Title: Technology Does Not Eliminate Close Calls
By: Chris Parker
While I’m on the topic of our recent sail from the Bahamas to Puerto Rico,
I’ve got another eye-opening story to tell.
Many friends, even some whose seamanship skills I respect, talk of how
they travel at night without navigation lights, monitoring the VHF and
otherwise maintaining a "proper watch." Some have reasonable excuses, such
as to remain invisible to pirates or common thieves (in some cruising
grounds this is a legitimate concern). Most choose to be invisible to save
precious amp-hours from their battery banks, or to avoid burning calories
on a trip below to flick the switch.
Bel Ami is a 1966 Morgan 34-foot sloop with a fiberglass hull and an
aluminum mast. We run an LED tricolor masthead light while under sail,
which sips only 200 milliamps and yet is visible at quite a distance. We
tested this LED against a 25-watt incandescent (drawing about 2.1 amps, or
10 times the electricity) two years ago. We found the 25-watt light
visible to five miles and the LED visible to three miles.
We also have a standard Davis radar reflector mounted below the port
spreader in the efficient rain-catcher orientation. We do not currently
have a radar, collision avoidance radar detector (CARD) or Sea-me unit
installed.
At about 0120 on Monday, May 3, 2004, at approximately 18 degrees 43
minutes N/67 degrees 20 minutes W (about 20 miles north of the Mona
Passage near Puerto Rico), I was on watch and spotted a single white light
on the horizon just forward of the starboard beam, appearing only while we
crested the 8-foot waves while sailing at a speed of 6.5 knots (beam reach
in 22 knots of wind) on a course of 190 magnetic toward the Mona.
About 10 minutes later, I could identify two shapes. Careful inspection
with our image-stabilized 14x binoculars clearly revealed two ships, one
with many lights -- including those designating a tug with tow -- and the
other a large, hulking thing on the horizon with one dim red light (the
tow). Over the previous 10 minutes, the bearing had not changed
appreciably, though this is sometimes difficult to discern from the deck
of a moving sailboat without aids such as a hand-bearing compass.
Some of the newer radar plotters do a fantastic job of effectively
smoothing the random sailboat movements and giving a precise indication of
range, bearing and whether that bearing is changing. We do not have such
fancy electronics, but they would only have confirmed we were on a
collision course.
Having identified a potentially close crossing, I hailed the tug, and he
responded. I gave my GPS position, course and speed, and asked the tug if
he thought we’d have issues. He responded that he was about to make a
course change to port and would pass to our stern. I confirmed we would
continue our course of 190 degrees at 6.5 knots toward the Mona. He knew
we were a 34-foot sailboat. I was relieved but keenly aware that we
remained on a collision course.
About five minutes later (0135 hours) I would estimate we were about three
to four miles apart. I hailed the tug again, gave my position, specified
my geographical proximity at 20 miles north of the Mona, and asked for his
confirmation that he was soon going to make a decisive turn to port. He
said he had me plotted eight miles away on radar, and he could see me, and
we’d be fine. He sure looked closer than that, but he had radar, and I
didn’t. I sat back uneasily for a few more minutes.
About three minutes later (0138 hours), I was sure we were only a couple
miles apart and hailed the tug again, offering my GPS position confirmed
on two GPS receivers. I said I thought we were getting uncomfortably close
to each other.
(If he had not previously told me he was changing course to port, I would
now be in the process of tacking away, but if he changed course to port
now, and I tacked, we’d be on a collision course on our new headings!)
He illuminated his spotlight and asked if I could see it, which I could. I
asked if he had a VISUAL contact on me, and he said he could clearly see
my green running light. He said he was in the process of making his turn
to port, and I should hold my course and speed, and we’d be OK.
About 60 seconds after we finished this discussion (0142 hours), I could
begin to see the white cresting waves of his bow wake and make out
specific features of the tug in the moonlight. He rose maybe 5 degrees
above the horizon, and the 600-foot tow was even higher on the horizon. As
I assessed the situation, I knew we were only about 200 yards apart, and I
would hit him somewhere in the aft-third of the tug (after years of
racing, I’m pretty good at assessing crossing situations).
With precious seconds passing and closing fast, I picked up the radio one
last time as we prepared to tack away. The tug responded, and I told him
we were way too close and that we were taking immediate and evasive
action. We were tacking now and would head north.
After I calmed down and cleaned my shorts, I reflected on the encounter.
The tug clearly never saw us on his radar. His radar contact was eight
miles away, when I’m quite sure we were only three miles apart, as
evidenced by the fact he said he could see me at that time.
Even after I gave him our GPS position three separate times, he failed to
identify our correct location relative to his. As soon as I had a doubt, I
clearly should have asked him for his GPS position. Had I done this, I
would have identified there was a certain crossing issue earlier.
There are many electronic marvels that could have assisted. (Let’s assume
the issue was my inadequate radar reflection rather than radar operator
error in interpreting the display.) A modern radar plotter would have
allowed us to make our own decisions earlier regarding the crossing. The
CARD system would not have helped, since it would simply tell us there’s
an active radar in the vicinity. We knew this already. While I do not
endorse the product, nor do I have any association whatsoever with the
company, the Sea-me unit could have made a real difference.
Sea-me is an active radar reflector. When struck by a radar beam, Sea-me
amplifies and reflects the amplified signal back to the sending unit. The
amplified signal makes the target appear much larger. The reflected signal
has an average radar cross section of 34 square meters, and I know vessels
using this device often appear like a ship on radar. This device also has
a radar detector, which alerts you to an active radar system in the area
(similar to the CARD, though CARD does have a directional display).
Sea-me is the only active radar reflector I am aware of, but there could
be other brands. I mention Sea-me to bring active radar reflectors to your
attention, not to endorse this brand specifically.
But all the electronic gadgetry in the world cannot replace the judgment
of an alert and qualified watch. Had we both been complacent enough to
believe all of the instruments we consulted, and had I been complacent
enough (after six days at sea on a rigorous upwind passage) to let my
guard down, we would not be enjoying the beautiful beaches and the
beautiful people of St. Thomas in the U.S. Virgin Islands today!
-- Chris Parker
cparker@oceannavigator.com
Related Articles
Title: Radar user blinded by heavy sea clutter
http://cms.navigatorpublishing.com/enewsl.asp?l=393
Title: Avoiding stealth
http://cms.navigatorpublishing.com/enewsl.asp?l=394
Author Bio:
Chris Parker is the author of "Coastal and Offshore Weather, the Essential
Handbook," and also is the forecaster for The Caribbean Weather Center. |
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